1 Explain 3G(WCDMA)Ans- WCDMA is a wideband Direct-Sequence Code Division Multiple Access (DS-CDMA) system ie user information bits are spread over a wide bandwidth by multiplying theuser data with quasi-random bits (called chips) derived from CDMA spreading codes In order to support very high bit rates (up to 2 Mbps) the use of a variable spreading factorand multicode connections is supported The chip rate of 384 Mcps leads to a carrier bandwidth of approximately 5 MHzWCDMA supports high user data rates and also has certain performance benefitsWCDMA supports two basic modes of operation Frequency Division Duplex (FDD) and Time Division Duplex (TDD) In the FDD mode separate 5 MHz carrier frequencies are used for the uplink and downlink respectively whereas in TDD only one 5 MHz is timeshared between the uplink and downlink Uplink is the connection from the mobile to the base station and downlink is that from the base station to the mobileFDD Technical summary-WCDMAFrequency band1920 MHz -1980 MHz and 2110 MHz - 2170 MHz (Frequency Division Duplex) Minimum frequency band required ~ 2x5MHzFrequency re-use 1Carrier Spacing 44MHz - 52 MHzMaximum number of (voice) channels on 2x5MHz ~196 (spreading factor 256 UL AMR 795kbps) ~98 (spreading factor 128 UL AMR 122kbps) Voice coding AMR codecs (475 kHz - 122 kHz GSM EFR=122 kHz) and SID (18 kHz)Channel coding Convolutional coding Turbo code for high rate dataDuplexer needed (190MHz separation) Asymmetric connection supportedReceiver sensitivity Node B -121dBm Mobile -117dBm at BER of 10-3Data type Packet and circuit switchModulation QPSKPulse shaping Root raised cosine roll-off = 022Chip rate 384 McpsChannel raster 200 kHzMaximum user data rate (Physical channel) ~ 23Mbps (spreading factor 4 parallel codes (3 DL 6 UL) 12 rate coding) but interference limitedMaximum user data rate (Offered) 384 kbps (year 2002) higher rates ( ~ 2 Mbps) in the near future HSPDA will offer data speeds up to 8-10 Mbps (and 20 Mbps for MIMO systems)Channel bit rate 576MbpsFrame length 10ms (38400 chips)Number of slots frame 15Number of chips slot 2560 chipsHandovers Soft Softer (interfrequency Hard)Power control period Time slot = 1500 Hz ratePower control step size 05 1 15 and 2 dB (Variable)Power control range UL 80dB DL 30dBMobile peak power Power class 1 +33 dBm (+1dB-3dB) = 2W class 2 +27 dBmclass 3 +24 dBmclass 4 +21 dBmNumber of unique base station identification codes 512 frequencyPhysical layer spreading factors 4 256 UL 4 512 DChannelization CodeThe channelization codes are Orthogonal Variable Spreading Factor (OVSF) codes They are used to preserve orthogonality between different physical channels They also increase the clock rate to 384 Mcps The OVSF codes are defined using a code treeIn the code tree the channelization codes are individually described by CchSFk where SF is the Spreading Factor of the code and k the code number 0 pound k pound SF-1A channelization sequence modulates one userrsquos bit Because the chip rate is constant the different lengths of codes enable to have different user data rates Low SFs are reserved for high rate services while high SFs are for low rate services The length of an OVSF code is an even number of chips and the number of codes (for one SF) is equal to the number of chips and to the SF value The generated codes within the same layer constitute a set of orthogonal codes Furthermore any two codes of different layers are orthogonal except when one of the two codes is a mother code of the other For example C43 is not orthogonal with C10 and C21 but is orthogonal with C20

Each Sector of each Base Station transmits W-CDMA Downlink Traffic Channels with up to 512 code channels Code tree repacking may be used to optimize the number of available codes in downlinkExercise Find code Cch83 and code Cch1615 OVSF shortage Scrambling enables neighboring cells to use the same channelization codes This allows the system to use a maximum of 512 OVSF codes in each cell Notice that the use of an OVSF code forbids the use of the other codes in its branch This reduces considerably the number of available codes especially for high rate services This may lead to an OVSF shortage In such a case secondary scrambling codes may be allocated to the cells and enable the reuse of the same OVSF in the same cellPrimary Scrambling Code GroupThere is a total of 512 primary codes They are further divided into 64 primary scrambling code groups of 8 primary scrambling codes each Each cell is allocated one and only one primary scrambling code The group of the primary scrambling code is found by the mobiles of the cell using the SCH while the specific primary scrambling code used is given by the CPICH The primary CCPCH and the primary CPICH channels are always scrambled with the primary scrambling code of the cell while other channels can be scrambled by either the primary or the secondary scrambling code Uplink scrambling codeAll the physical channels in the uplink are scrambled In uplink the scrambling code can be described as either long or short depending on the way it was constructed The scrambling code is always applied to one 10 ms frame Different scrambling codes will be allocated to different mobiles In UMTS Gold codes were chosen for their very low peak cross-correlation Downlink link scrambling codeThe scrambling codes used in downlink are constructed like the long uplink scrambling codes They are created with two 18-cell shift registers 218-1 = 262143 different scrambling codes can be formed using this method However not all of them are used The downlink scrambling codes are divided into 512 sets of one primary scrambling code and 15 secondary scrambling codes each The primary scrambling codes are scrambling codes n=16i where i=0hellip511 The 15 secondary scrambling codes associated to one primary scrambling code are n=16i + k where k=1hellip15 For now 8192 scrambling codes have been defined 2 What is UMTSAns-UMTS is one of the Third Generation (3G) mobile systems being developed within the ITUs IMT-2000 framework It is a realisation of a new generation of broadband multi-media mobile telecommunications technology The coverage area of service provision is to be world wide in the form of FLMTS (Future Land Mobile Telecommunications Services and now called IMT2000) The coverage will be provided by a combination of cell sizes ranging from in building Pico Cells to Global Cells provided by satellite giving service to the remote regions of the world The UMTS is not a replacement of 2nd generation technologies (eg GSM DCS1800 CDMA DECT etc) which will continue to evolve to their full potential3what is WCDMA Frequency and Spectrum

Uplink=1920MHz -1980 MHz Downlink= 2110MHz -2170MHz Duplex Frequency 2110-1920 = 190 MHz Bandwidth 1980-1920 = 60 MHz Carriers 60 5 = 12

In WCDMA frequency reuse factor =1 ULDL(Aircel AP-197660UL216660DL) 4 Why is WCDMA called WidebandAns-3G WCDMA systems have 5MHz bandwidth (one direction) 5MHz is neither wide nor narrow it is just the bandwidth New 3G WCDMA systems have wider bandwidth than existing 2G cdma systems (cdmaOne 125MHz) thats why the Wide There are commercial cdma systems with 20MHz bandwidth5 What is Difference between 3G and 2G Ans-3G(WCDMA) is Based on CDMA techonology

6 Active setamp Monitored setamp Detected setActive set- the set of cells with which the UE is currently connectedcommunicating with MSusually show them as SC or Pilots but they are actually Communicating with MS cellsTypical Active set size is 3 or 4Monitored set- Cells which are not included in the active set but are included in the CELL_INFO_LIST belong to the Monitored Setlike nighboring cell listDetected set- Cells detected by the UE which are neither in the CELL_INFO_LIST nor in the active set belong to the Detected Set Reporting of measurements of the detected set is only applicable to intra-frequency measurements made by UEs in CELL_DCH state

7 what is RSCPampEcIoampRSSIampEbNo Ans-RSCP- stands for Received Signal Code Powerthatrsquos the power lavel the pilot cahnnel of a cell is recevied with and usually Expressed in dBMWith this parametersdifferent cell using the same carrier can be campared and handover or cell reseclection dicisions can be takenWhat isEcIo- EcIo is the ratio of the energy per chip in CPICH to the total received power density (including CPICH itself)What is EbNo- By definition EbNo is energy bit over noise density ie is the ratio of the energy per information bit to the power spectral density (of interference and noise) after dispreading EbNo = Processing Gain + SIRFor example if EbNo is 5dB and processing gain is 25dB then the SIR should be -20dB or betterWhat is SIR- SIR is the Signal-to-Interference Ratio ndash the ratio of the energy in dedicated physical control channel bits to the power density of interference and noise after dispreadingEcNo lt -8 db good quality of signal and no of the already discussedalgorithms (IRATH CM and CSR) may be triggered in this interval1048707 -12 db lt EcNo lt -8 db acceptable quality of signal UE enters in compressed mode when EcNo = -12 db1048707 -18 db lt EcNo lt -12 db signal can be decoded with a modest qualityUE is in compressed mode UEs existing in this area consume a greatamount of resources (power codes hellip)1048707 EcNo lt -18 db signal cannot be decoded UE moves to GSM (if it ispossible)8Sometimes we say EcIo and sometimes we say EcNo are they differentIo = own cell interference + surrounding cell interference + noise densityNo = surrounding cell interference + noise densityThat is Io is the total received power density including CPICH of its own cell No is the total received power density excluding CPICH of its own cell Technically EcIo should be the correct measurement but due to equipment capability EcNo is actually measured In UMTS EcNo and EcIo are often used interchangeablyThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the CN for example management of connections to the UEThe RNC controlling one Node B (ie terminating the Iub interface towards the Node B) is indicated as the Controlling RNC (CRNC) of the Node B The Controlling RNC is responsible for the load and congestion control of its own cells and also executes the admission control and code allocation for new radio links to be established in those cellsThe Node B (Base Station)The main function of the Node B is to perform the air interface L1 processing (channel coding and interleaving rate adaptation spreading etc) It also performs some basic Radio Resource Management operations such as the inner loop power control It logically corresponds to the GSM Base Station The enigmatic term lsquoNode Brsquo was initially adopted as a temporary term during the standardisation process but then never changedRAB (Radio Access Bearer) Management This function combines all RAB handlingndash RAB Set-up including the possibility for queuing the set-upndash modification of the characteristics of an existing RABndash clearing an existing RAB including the RAN-initiated case9 what is Pilot PollutionPilot pollution means that there are too many strong Cells within the coverage but none of the pilots is dominantSimply speaking when the number of strong cells exceeds the active set size there is ldquopilot pollutionrdquo in the area Typically the active set size is 3 so if there are more than 3 strong cells then there is pilot pollution Definition of ldquostrong cellrdquo pilots within the handover window size from the strongest cell

Typical handover window size is between 4 to 6dB For example if there are more than 2 cells (besides the strongest cell) within 4dB of the strongest cell then there is pilot pollutionIn idle or cell_FACH mode phenomenon of the pilot pollution is that a UE can not firmly camp on a cell at one location because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) The condition to determine the area has pilot pollution in idle or cell_FACH mode is that third pilot appears in the cell re-selection regionIn cell_DCH mode phenomenon of the pilot pollution is that a UE at one location frequently changes its active set cells (active set update rate is very high) because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) It causes high signaling load in RRC and Iub interfaces and the capacity of RNC is consequently reducedThe condition to determine the area has pilot pollution in cell_DCH mode is the number of pilots within the Reporting Range 1b threshold for drop window range is larger than Max Active Set

Effect of Pilot Pollution High BLER Low system capacity High call drop rate due to frequent handover Low access success rate due to no dominant cell

HOW TO REDUCE THE PILOT POLLUTION PROBLEM Maximise the signal inside the best server Minimise the energy overshoot from the neighbor cells with some RF consideration (tilt azimuthhellip) Proper transmit power and power ratio of sites Probable Solution adjust engineering parameters of an antenna so that a best server forms around the

antenna For handover problems caused by pilot pollution adjust engineering parameters of other antennas so that signals from other antennas becomes weaker and the number of pilots drops

10 what is the Power control whay we need3G(FDD-WCDMA) is Based on CDMA techonology here we have a One frequency 5MHz ULDLwe are using same frequency every ware in the siteswe can see that wcdma we are using 1 Frequency in all sites so every ware is Co-Cahnnel so itrsquos criate a latoff interfarance every ware so minimize the interfarane powercontrol is interdiusedExplain Near far effectAll users use the same bandwidth at the same time and therefore users interfere with one another Due to the propagation path loss the signal received by the base station from a UE close to the base station will be stronger than the Signal received from another terminal located at the boundary Hence the distant user will be dominated by the close user This is called the near-far effect To achieve a considerable capacity all signals irrespective of distance should arrive at the base station with the same mean power A solution to this problem is power control which attempts to achieve the same mean received power for each userFor example Mobile stations UE1 and UE2 operate within the same frequency separable at the base station only by their respective spreading codes It may happen that UE2 at the cell edge suffers a path loss say 70 dB above that of UE1 which is near the base station BS If there were no mechanism for UE1 and UE2 to be power-controlled to the same level at the base station UE1 could easily to mask UE2 and thus block a large part of the cell so-called near-far problem of CDMA The optimum strategy in the sense of maximizing capacity is to equalize the received power per bit of all mobile station at all times Power Control in WCDMA 15 KHz(1500 TimsSec) Its objective is to maximize capacity by minimizing power and interference

Open Loop Power Control middot Uplink open-loop power control middot Downlink open-loop power control

Closed-loop power control Outer-loop power control

Uplink outer-loop power control Downlink outer-loop power control

Inner-loop power control Uplink inner-loop power control Downlink inner-loop power control

Open-loop power control is used to set the initial power of UE (in random access) and downlink channels The TPC commands used in inner-loop power control are relative so it needs a starting point and this is defined by open-loop power control Also this is useful in setting the power level in case of common shared channels where it is difficult to send each UE the necessary TPC commands In case of uplink UE and broadcasted cellsystem parameters are used to set initial access power on RACH And in case of downlink the measurement report of UE is used to set the initial power of downlink channelsThe open loop power control tolerance is plusmn9dB under normal conditions and plusmn12dB under extreme conditionsClosed-loop power control is the power control mechanism used in UMTS to solve near-far problem minimize interference and to keep the signal quality to optimum level Closed-loop power control is used in uplink (UL) as well as downlink (DL) However the motive in both the cases are different In uplink signals from different UEs reach NodeB with different power strength thus causing the stronger signal blocking the weaker one resulting in near-far effect In downlink there is no near-far effect but the UEs near the cell-edge or in high interference region may need extra power to overcome the increased other cell interference and weak signal due to Rayleigh fadingClosed-loop power control can be divided into outer-loop and inner-loop power control In case of uplink the RNC manages the outer-loop and Node B manages the inner-loop and for downlink UE manages the outer-loop and Node B manages the inner-loopInner-loop power control (also called fast closed-loop power control) operates at 1500 times per sec (15 kHz) [From where did this value of 15 kHz come from Answer A UMTS 10 ms frame consists of 15 TPC commands This results in a power control frequency of 1500 Hz (1510ms)] and relies on the feedback information from the opposite end of the link (or channel) to maintain the signal to interference (noise) ratio to a target level set by the outer-loop power control The transmission power is increased or decreased by a certain fixed step size depending on whether the received SIR is below or above the target SIR Precise power control can lead to optimum use of bandwidth resulting in increase cell capacity

The UL inner-loop power control lets the UE adjust its output power in accordance with one or more TPC commands received in the downlink direction Remember the increase and decrease in power is limited by upper and lower bounds as defined in 3GPP TS 25101 The upper bound ie UE maximum output power is set depending on the Power class of UE This can also be set below the maximum capability of the UE through signaling when the link is established The lower bound ie UE minimum output power defined as the mean power in one timeslot (TS) and shall be less than -50 dB

The DL inner-loop power control is used to control the transmission power of downlink channels at Node B as per the TPC commands received from UE However in some situations Node B may ignore the increasedecrease these TPC commands For example in case of congestion (high load scenario) the Node B can ignore the TPC commands from UE

Outer-loop power control is used to set the target quality value for inner-loop power control ie it adjusts the target SIR in Node B which is used during inner-loop power control Now the question is why do we need to adjust the target SIR Outer-loop power control tries to keep the quality of a connection to desired value Too high quality will waste the resources

11 What is Handover(SoftSofterHardInter-freq)Ans- Handover (Handoff)-Handover is a process in mobile communications in which a connected cellular call or a data session is transferred from one cell site (base station)to another Cell site without disconnecting

the session As a key component of the mobile communication system the cell has a limited coverage area The primary function of the handover is to provide the continuous service for the moving UEs in the coverage of the networkDifferent types of handovers have been introduced in the UMTS systemhere in WCDMA we have a few handovers

SoftSofter Handover Hard Handover Intra-System handover

Intra-frequency handover Inter-frequency handover

Inter-System handover

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Each Sector of each Base Station transmits W-CDMA Downlink Traffic Channels with up to 512 code channels Code tree repacking may be used to optimize the number of available codes in downlinkExercise Find code Cch83 and code Cch1615 OVSF shortage Scrambling enables neighboring cells to use the same channelization codes This allows the system to use a maximum of 512 OVSF codes in each cell Notice that the use of an OVSF code forbids the use of the other codes in its branch This reduces considerably the number of available codes especially for high rate services This may lead to an OVSF shortage In such a case secondary scrambling codes may be allocated to the cells and enable the reuse of the same OVSF in the same cellPrimary Scrambling Code GroupThere is a total of 512 primary codes They are further divided into 64 primary scrambling code groups of 8 primary scrambling codes each Each cell is allocated one and only one primary scrambling code The group of the primary scrambling code is found by the mobiles of the cell using the SCH while the specific primary scrambling code used is given by the CPICH The primary CCPCH and the primary CPICH channels are always scrambled with the primary scrambling code of the cell while other channels can be scrambled by either the primary or the secondary scrambling code Uplink scrambling codeAll the physical channels in the uplink are scrambled In uplink the scrambling code can be described as either long or short depending on the way it was constructed The scrambling code is always applied to one 10 ms frame Different scrambling codes will be allocated to different mobiles In UMTS Gold codes were chosen for their very low peak cross-correlation Downlink link scrambling codeThe scrambling codes used in downlink are constructed like the long uplink scrambling codes They are created with two 18-cell shift registers 218-1 = 262143 different scrambling codes can be formed using this method However not all of them are used The downlink scrambling codes are divided into 512 sets of one primary scrambling code and 15 secondary scrambling codes each The primary scrambling codes are scrambling codes n=16i where i=0hellip511 The 15 secondary scrambling codes associated to one primary scrambling code are n=16i + k where k=1hellip15 For now 8192 scrambling codes have been defined 2 What is UMTSAns-UMTS is one of the Third Generation (3G) mobile systems being developed within the ITUs IMT-2000 framework It is a realisation of a new generation of broadband multi-media mobile telecommunications technology The coverage area of service provision is to be world wide in the form of FLMTS (Future Land Mobile Telecommunications Services and now called IMT2000) The coverage will be provided by a combination of cell sizes ranging from in building Pico Cells to Global Cells provided by satellite giving service to the remote regions of the world The UMTS is not a replacement of 2nd generation technologies (eg GSM DCS1800 CDMA DECT etc) which will continue to evolve to their full potential3what is WCDMA Frequency and Spectrum

Uplink=1920MHz -1980 MHz Downlink= 2110MHz -2170MHz Duplex Frequency 2110-1920 = 190 MHz Bandwidth 1980-1920 = 60 MHz Carriers 60 5 = 12

In WCDMA frequency reuse factor =1 ULDL(Aircel AP-197660UL216660DL) 4 Why is WCDMA called WidebandAns-3G WCDMA systems have 5MHz bandwidth (one direction) 5MHz is neither wide nor narrow it is just the bandwidth New 3G WCDMA systems have wider bandwidth than existing 2G cdma systems (cdmaOne 125MHz) thats why the Wide There are commercial cdma systems with 20MHz bandwidth5 What is Difference between 3G and 2G Ans-3G(WCDMA) is Based on CDMA techonology

6 Active setamp Monitored setamp Detected setActive set- the set of cells with which the UE is currently connectedcommunicating with MSusually show them as SC or Pilots but they are actually Communicating with MS cellsTypical Active set size is 3 or 4Monitored set- Cells which are not included in the active set but are included in the CELL_INFO_LIST belong to the Monitored Setlike nighboring cell listDetected set- Cells detected by the UE which are neither in the CELL_INFO_LIST nor in the active set belong to the Detected Set Reporting of measurements of the detected set is only applicable to intra-frequency measurements made by UEs in CELL_DCH state

7 what is RSCPampEcIoampRSSIampEbNo Ans-RSCP- stands for Received Signal Code Powerthatrsquos the power lavel the pilot cahnnel of a cell is recevied with and usually Expressed in dBMWith this parametersdifferent cell using the same carrier can be campared and handover or cell reseclection dicisions can be takenWhat isEcIo- EcIo is the ratio of the energy per chip in CPICH to the total received power density (including CPICH itself)What is EbNo- By definition EbNo is energy bit over noise density ie is the ratio of the energy per information bit to the power spectral density (of interference and noise) after dispreading EbNo = Processing Gain + SIRFor example if EbNo is 5dB and processing gain is 25dB then the SIR should be -20dB or betterWhat is SIR- SIR is the Signal-to-Interference Ratio ndash the ratio of the energy in dedicated physical control channel bits to the power density of interference and noise after dispreadingEcNo lt -8 db good quality of signal and no of the already discussedalgorithms (IRATH CM and CSR) may be triggered in this interval1048707 -12 db lt EcNo lt -8 db acceptable quality of signal UE enters in compressed mode when EcNo = -12 db1048707 -18 db lt EcNo lt -12 db signal can be decoded with a modest qualityUE is in compressed mode UEs existing in this area consume a greatamount of resources (power codes hellip)1048707 EcNo lt -18 db signal cannot be decoded UE moves to GSM (if it ispossible)8Sometimes we say EcIo and sometimes we say EcNo are they differentIo = own cell interference + surrounding cell interference + noise densityNo = surrounding cell interference + noise densityThat is Io is the total received power density including CPICH of its own cell No is the total received power density excluding CPICH of its own cell Technically EcIo should be the correct measurement but due to equipment capability EcNo is actually measured In UMTS EcNo and EcIo are often used interchangeablyThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the CN for example management of connections to the UEThe RNC controlling one Node B (ie terminating the Iub interface towards the Node B) is indicated as the Controlling RNC (CRNC) of the Node B The Controlling RNC is responsible for the load and congestion control of its own cells and also executes the admission control and code allocation for new radio links to be established in those cellsThe Node B (Base Station)The main function of the Node B is to perform the air interface L1 processing (channel coding and interleaving rate adaptation spreading etc) It also performs some basic Radio Resource Management operations such as the inner loop power control It logically corresponds to the GSM Base Station The enigmatic term lsquoNode Brsquo was initially adopted as a temporary term during the standardisation process but then never changedRAB (Radio Access Bearer) Management This function combines all RAB handlingndash RAB Set-up including the possibility for queuing the set-upndash modification of the characteristics of an existing RABndash clearing an existing RAB including the RAN-initiated case9 what is Pilot PollutionPilot pollution means that there are too many strong Cells within the coverage but none of the pilots is dominantSimply speaking when the number of strong cells exceeds the active set size there is ldquopilot pollutionrdquo in the area Typically the active set size is 3 so if there are more than 3 strong cells then there is pilot pollution Definition of ldquostrong cellrdquo pilots within the handover window size from the strongest cell

Typical handover window size is between 4 to 6dB For example if there are more than 2 cells (besides the strongest cell) within 4dB of the strongest cell then there is pilot pollutionIn idle or cell_FACH mode phenomenon of the pilot pollution is that a UE can not firmly camp on a cell at one location because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) The condition to determine the area has pilot pollution in idle or cell_FACH mode is that third pilot appears in the cell re-selection regionIn cell_DCH mode phenomenon of the pilot pollution is that a UE at one location frequently changes its active set cells (active set update rate is very high) because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) It causes high signaling load in RRC and Iub interfaces and the capacity of RNC is consequently reducedThe condition to determine the area has pilot pollution in cell_DCH mode is the number of pilots within the Reporting Range 1b threshold for drop window range is larger than Max Active Set

Effect of Pilot Pollution High BLER Low system capacity High call drop rate due to frequent handover Low access success rate due to no dominant cell

HOW TO REDUCE THE PILOT POLLUTION PROBLEM Maximise the signal inside the best server Minimise the energy overshoot from the neighbor cells with some RF consideration (tilt azimuthhellip) Proper transmit power and power ratio of sites Probable Solution adjust engineering parameters of an antenna so that a best server forms around the

antenna For handover problems caused by pilot pollution adjust engineering parameters of other antennas so that signals from other antennas becomes weaker and the number of pilots drops

10 what is the Power control whay we need3G(FDD-WCDMA) is Based on CDMA techonology here we have a One frequency 5MHz ULDLwe are using same frequency every ware in the siteswe can see that wcdma we are using 1 Frequency in all sites so every ware is Co-Cahnnel so itrsquos criate a latoff interfarance every ware so minimize the interfarane powercontrol is interdiusedExplain Near far effectAll users use the same bandwidth at the same time and therefore users interfere with one another Due to the propagation path loss the signal received by the base station from a UE close to the base station will be stronger than the Signal received from another terminal located at the boundary Hence the distant user will be dominated by the close user This is called the near-far effect To achieve a considerable capacity all signals irrespective of distance should arrive at the base station with the same mean power A solution to this problem is power control which attempts to achieve the same mean received power for each userFor example Mobile stations UE1 and UE2 operate within the same frequency separable at the base station only by their respective spreading codes It may happen that UE2 at the cell edge suffers a path loss say 70 dB above that of UE1 which is near the base station BS If there were no mechanism for UE1 and UE2 to be power-controlled to the same level at the base station UE1 could easily to mask UE2 and thus block a large part of the cell so-called near-far problem of CDMA The optimum strategy in the sense of maximizing capacity is to equalize the received power per bit of all mobile station at all times Power Control in WCDMA 15 KHz(1500 TimsSec) Its objective is to maximize capacity by minimizing power and interference

Open Loop Power Control middot Uplink open-loop power control middot Downlink open-loop power control

Closed-loop power control Outer-loop power control

Uplink outer-loop power control Downlink outer-loop power control

Inner-loop power control Uplink inner-loop power control Downlink inner-loop power control

Open-loop power control is used to set the initial power of UE (in random access) and downlink channels The TPC commands used in inner-loop power control are relative so it needs a starting point and this is defined by open-loop power control Also this is useful in setting the power level in case of common shared channels where it is difficult to send each UE the necessary TPC commands In case of uplink UE and broadcasted cellsystem parameters are used to set initial access power on RACH And in case of downlink the measurement report of UE is used to set the initial power of downlink channelsThe open loop power control tolerance is plusmn9dB under normal conditions and plusmn12dB under extreme conditionsClosed-loop power control is the power control mechanism used in UMTS to solve near-far problem minimize interference and to keep the signal quality to optimum level Closed-loop power control is used in uplink (UL) as well as downlink (DL) However the motive in both the cases are different In uplink signals from different UEs reach NodeB with different power strength thus causing the stronger signal blocking the weaker one resulting in near-far effect In downlink there is no near-far effect but the UEs near the cell-edge or in high interference region may need extra power to overcome the increased other cell interference and weak signal due to Rayleigh fadingClosed-loop power control can be divided into outer-loop and inner-loop power control In case of uplink the RNC manages the outer-loop and Node B manages the inner-loop and for downlink UE manages the outer-loop and Node B manages the inner-loopInner-loop power control (also called fast closed-loop power control) operates at 1500 times per sec (15 kHz) [From where did this value of 15 kHz come from Answer A UMTS 10 ms frame consists of 15 TPC commands This results in a power control frequency of 1500 Hz (1510ms)] and relies on the feedback information from the opposite end of the link (or channel) to maintain the signal to interference (noise) ratio to a target level set by the outer-loop power control The transmission power is increased or decreased by a certain fixed step size depending on whether the received SIR is below or above the target SIR Precise power control can lead to optimum use of bandwidth resulting in increase cell capacity

The UL inner-loop power control lets the UE adjust its output power in accordance with one or more TPC commands received in the downlink direction Remember the increase and decrease in power is limited by upper and lower bounds as defined in 3GPP TS 25101 The upper bound ie UE maximum output power is set depending on the Power class of UE This can also be set below the maximum capability of the UE through signaling when the link is established The lower bound ie UE minimum output power defined as the mean power in one timeslot (TS) and shall be less than -50 dB

The DL inner-loop power control is used to control the transmission power of downlink channels at Node B as per the TPC commands received from UE However in some situations Node B may ignore the increasedecrease these TPC commands For example in case of congestion (high load scenario) the Node B can ignore the TPC commands from UE

Outer-loop power control is used to set the target quality value for inner-loop power control ie it adjusts the target SIR in Node B which is used during inner-loop power control Now the question is why do we need to adjust the target SIR Outer-loop power control tries to keep the quality of a connection to desired value Too high quality will waste the resources

11 What is Handover(SoftSofterHardInter-freq)Ans- Handover (Handoff)-Handover is a process in mobile communications in which a connected cellular call or a data session is transferred from one cell site (base station)to another Cell site without disconnecting

the session As a key component of the mobile communication system the cell has a limited coverage area The primary function of the handover is to provide the continuous service for the moving UEs in the coverage of the networkDifferent types of handovers have been introduced in the UMTS systemhere in WCDMA we have a few handovers

SoftSofter Handover Hard Handover Intra-System handover

Intra-frequency handover Inter-frequency handover

Inter-System handover

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

6 Active setamp Monitored setamp Detected setActive set- the set of cells with which the UE is currently connectedcommunicating with MSusually show them as SC or Pilots but they are actually Communicating with MS cellsTypical Active set size is 3 or 4Monitored set- Cells which are not included in the active set but are included in the CELL_INFO_LIST belong to the Monitored Setlike nighboring cell listDetected set- Cells detected by the UE which are neither in the CELL_INFO_LIST nor in the active set belong to the Detected Set Reporting of measurements of the detected set is only applicable to intra-frequency measurements made by UEs in CELL_DCH state

7 what is RSCPampEcIoampRSSIampEbNo Ans-RSCP- stands for Received Signal Code Powerthatrsquos the power lavel the pilot cahnnel of a cell is recevied with and usually Expressed in dBMWith this parametersdifferent cell using the same carrier can be campared and handover or cell reseclection dicisions can be takenWhat isEcIo- EcIo is the ratio of the energy per chip in CPICH to the total received power density (including CPICH itself)What is EbNo- By definition EbNo is energy bit over noise density ie is the ratio of the energy per information bit to the power spectral density (of interference and noise) after dispreading EbNo = Processing Gain + SIRFor example if EbNo is 5dB and processing gain is 25dB then the SIR should be -20dB or betterWhat is SIR- SIR is the Signal-to-Interference Ratio ndash the ratio of the energy in dedicated physical control channel bits to the power density of interference and noise after dispreadingEcNo lt -8 db good quality of signal and no of the already discussedalgorithms (IRATH CM and CSR) may be triggered in this interval1048707 -12 db lt EcNo lt -8 db acceptable quality of signal UE enters in compressed mode when EcNo = -12 db1048707 -18 db lt EcNo lt -12 db signal can be decoded with a modest qualityUE is in compressed mode UEs existing in this area consume a greatamount of resources (power codes hellip)1048707 EcNo lt -18 db signal cannot be decoded UE moves to GSM (if it ispossible)8Sometimes we say EcIo and sometimes we say EcNo are they differentIo = own cell interference + surrounding cell interference + noise densityNo = surrounding cell interference + noise densityThat is Io is the total received power density including CPICH of its own cell No is the total received power density excluding CPICH of its own cell Technically EcIo should be the correct measurement but due to equipment capability EcNo is actually measured In UMTS EcNo and EcIo are often used interchangeablyThe Radio Network Controller (RNC) owns and controls the radio resources in its domain (the Node Bs connected to it) RNC is the service access point for all services UTRAN provides the CN for example management of connections to the UEThe RNC controlling one Node B (ie terminating the Iub interface towards the Node B) is indicated as the Controlling RNC (CRNC) of the Node B The Controlling RNC is responsible for the load and congestion control of its own cells and also executes the admission control and code allocation for new radio links to be established in those cellsThe Node B (Base Station)The main function of the Node B is to perform the air interface L1 processing (channel coding and interleaving rate adaptation spreading etc) It also performs some basic Radio Resource Management operations such as the inner loop power control It logically corresponds to the GSM Base Station The enigmatic term lsquoNode Brsquo was initially adopted as a temporary term during the standardisation process but then never changedRAB (Radio Access Bearer) Management This function combines all RAB handlingndash RAB Set-up including the possibility for queuing the set-upndash modification of the characteristics of an existing RABndash clearing an existing RAB including the RAN-initiated case9 what is Pilot PollutionPilot pollution means that there are too many strong Cells within the coverage but none of the pilots is dominantSimply speaking when the number of strong cells exceeds the active set size there is ldquopilot pollutionrdquo in the area Typically the active set size is 3 so if there are more than 3 strong cells then there is pilot pollution Definition of ldquostrong cellrdquo pilots within the handover window size from the strongest cell

Typical handover window size is between 4 to 6dB For example if there are more than 2 cells (besides the strongest cell) within 4dB of the strongest cell then there is pilot pollutionIn idle or cell_FACH mode phenomenon of the pilot pollution is that a UE can not firmly camp on a cell at one location because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) The condition to determine the area has pilot pollution in idle or cell_FACH mode is that third pilot appears in the cell re-selection regionIn cell_DCH mode phenomenon of the pilot pollution is that a UE at one location frequently changes its active set cells (active set update rate is very high) because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) It causes high signaling load in RRC and Iub interfaces and the capacity of RNC is consequently reducedThe condition to determine the area has pilot pollution in cell_DCH mode is the number of pilots within the Reporting Range 1b threshold for drop window range is larger than Max Active Set

Effect of Pilot Pollution High BLER Low system capacity High call drop rate due to frequent handover Low access success rate due to no dominant cell

HOW TO REDUCE THE PILOT POLLUTION PROBLEM Maximise the signal inside the best server Minimise the energy overshoot from the neighbor cells with some RF consideration (tilt azimuthhellip) Proper transmit power and power ratio of sites Probable Solution adjust engineering parameters of an antenna so that a best server forms around the

antenna For handover problems caused by pilot pollution adjust engineering parameters of other antennas so that signals from other antennas becomes weaker and the number of pilots drops

10 what is the Power control whay we need3G(FDD-WCDMA) is Based on CDMA techonology here we have a One frequency 5MHz ULDLwe are using same frequency every ware in the siteswe can see that wcdma we are using 1 Frequency in all sites so every ware is Co-Cahnnel so itrsquos criate a latoff interfarance every ware so minimize the interfarane powercontrol is interdiusedExplain Near far effectAll users use the same bandwidth at the same time and therefore users interfere with one another Due to the propagation path loss the signal received by the base station from a UE close to the base station will be stronger than the Signal received from another terminal located at the boundary Hence the distant user will be dominated by the close user This is called the near-far effect To achieve a considerable capacity all signals irrespective of distance should arrive at the base station with the same mean power A solution to this problem is power control which attempts to achieve the same mean received power for each userFor example Mobile stations UE1 and UE2 operate within the same frequency separable at the base station only by their respective spreading codes It may happen that UE2 at the cell edge suffers a path loss say 70 dB above that of UE1 which is near the base station BS If there were no mechanism for UE1 and UE2 to be power-controlled to the same level at the base station UE1 could easily to mask UE2 and thus block a large part of the cell so-called near-far problem of CDMA The optimum strategy in the sense of maximizing capacity is to equalize the received power per bit of all mobile station at all times Power Control in WCDMA 15 KHz(1500 TimsSec) Its objective is to maximize capacity by minimizing power and interference

Open Loop Power Control middot Uplink open-loop power control middot Downlink open-loop power control

Closed-loop power control Outer-loop power control

Uplink outer-loop power control Downlink outer-loop power control

Inner-loop power control Uplink inner-loop power control Downlink inner-loop power control

Open-loop power control is used to set the initial power of UE (in random access) and downlink channels The TPC commands used in inner-loop power control are relative so it needs a starting point and this is defined by open-loop power control Also this is useful in setting the power level in case of common shared channels where it is difficult to send each UE the necessary TPC commands In case of uplink UE and broadcasted cellsystem parameters are used to set initial access power on RACH And in case of downlink the measurement report of UE is used to set the initial power of downlink channelsThe open loop power control tolerance is plusmn9dB under normal conditions and plusmn12dB under extreme conditionsClosed-loop power control is the power control mechanism used in UMTS to solve near-far problem minimize interference and to keep the signal quality to optimum level Closed-loop power control is used in uplink (UL) as well as downlink (DL) However the motive in both the cases are different In uplink signals from different UEs reach NodeB with different power strength thus causing the stronger signal blocking the weaker one resulting in near-far effect In downlink there is no near-far effect but the UEs near the cell-edge or in high interference region may need extra power to overcome the increased other cell interference and weak signal due to Rayleigh fadingClosed-loop power control can be divided into outer-loop and inner-loop power control In case of uplink the RNC manages the outer-loop and Node B manages the inner-loop and for downlink UE manages the outer-loop and Node B manages the inner-loopInner-loop power control (also called fast closed-loop power control) operates at 1500 times per sec (15 kHz) [From where did this value of 15 kHz come from Answer A UMTS 10 ms frame consists of 15 TPC commands This results in a power control frequency of 1500 Hz (1510ms)] and relies on the feedback information from the opposite end of the link (or channel) to maintain the signal to interference (noise) ratio to a target level set by the outer-loop power control The transmission power is increased or decreased by a certain fixed step size depending on whether the received SIR is below or above the target SIR Precise power control can lead to optimum use of bandwidth resulting in increase cell capacity

The UL inner-loop power control lets the UE adjust its output power in accordance with one or more TPC commands received in the downlink direction Remember the increase and decrease in power is limited by upper and lower bounds as defined in 3GPP TS 25101 The upper bound ie UE maximum output power is set depending on the Power class of UE This can also be set below the maximum capability of the UE through signaling when the link is established The lower bound ie UE minimum output power defined as the mean power in one timeslot (TS) and shall be less than -50 dB

The DL inner-loop power control is used to control the transmission power of downlink channels at Node B as per the TPC commands received from UE However in some situations Node B may ignore the increasedecrease these TPC commands For example in case of congestion (high load scenario) the Node B can ignore the TPC commands from UE

Outer-loop power control is used to set the target quality value for inner-loop power control ie it adjusts the target SIR in Node B which is used during inner-loop power control Now the question is why do we need to adjust the target SIR Outer-loop power control tries to keep the quality of a connection to desired value Too high quality will waste the resources

11 What is Handover(SoftSofterHardInter-freq)Ans- Handover (Handoff)-Handover is a process in mobile communications in which a connected cellular call or a data session is transferred from one cell site (base station)to another Cell site without disconnecting

the session As a key component of the mobile communication system the cell has a limited coverage area The primary function of the handover is to provide the continuous service for the moving UEs in the coverage of the networkDifferent types of handovers have been introduced in the UMTS systemhere in WCDMA we have a few handovers

SoftSofter Handover Hard Handover Intra-System handover

Intra-frequency handover Inter-frequency handover

Inter-System handover

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Typical handover window size is between 4 to 6dB For example if there are more than 2 cells (besides the strongest cell) within 4dB of the strongest cell then there is pilot pollutionIn idle or cell_FACH mode phenomenon of the pilot pollution is that a UE can not firmly camp on a cell at one location because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) The condition to determine the area has pilot pollution in idle or cell_FACH mode is that third pilot appears in the cell re-selection regionIn cell_DCH mode phenomenon of the pilot pollution is that a UE at one location frequently changes its active set cells (active set update rate is very high) because of receiving many pilot channels with similar quality (or signal strength) ie EcNo (or RSCP) It causes high signaling load in RRC and Iub interfaces and the capacity of RNC is consequently reducedThe condition to determine the area has pilot pollution in cell_DCH mode is the number of pilots within the Reporting Range 1b threshold for drop window range is larger than Max Active Set

Effect of Pilot Pollution High BLER Low system capacity High call drop rate due to frequent handover Low access success rate due to no dominant cell

HOW TO REDUCE THE PILOT POLLUTION PROBLEM Maximise the signal inside the best server Minimise the energy overshoot from the neighbor cells with some RF consideration (tilt azimuthhellip) Proper transmit power and power ratio of sites Probable Solution adjust engineering parameters of an antenna so that a best server forms around the

antenna For handover problems caused by pilot pollution adjust engineering parameters of other antennas so that signals from other antennas becomes weaker and the number of pilots drops

10 what is the Power control whay we need3G(FDD-WCDMA) is Based on CDMA techonology here we have a One frequency 5MHz ULDLwe are using same frequency every ware in the siteswe can see that wcdma we are using 1 Frequency in all sites so every ware is Co-Cahnnel so itrsquos criate a latoff interfarance every ware so minimize the interfarane powercontrol is interdiusedExplain Near far effectAll users use the same bandwidth at the same time and therefore users interfere with one another Due to the propagation path loss the signal received by the base station from a UE close to the base station will be stronger than the Signal received from another terminal located at the boundary Hence the distant user will be dominated by the close user This is called the near-far effect To achieve a considerable capacity all signals irrespective of distance should arrive at the base station with the same mean power A solution to this problem is power control which attempts to achieve the same mean received power for each userFor example Mobile stations UE1 and UE2 operate within the same frequency separable at the base station only by their respective spreading codes It may happen that UE2 at the cell edge suffers a path loss say 70 dB above that of UE1 which is near the base station BS If there were no mechanism for UE1 and UE2 to be power-controlled to the same level at the base station UE1 could easily to mask UE2 and thus block a large part of the cell so-called near-far problem of CDMA The optimum strategy in the sense of maximizing capacity is to equalize the received power per bit of all mobile station at all times Power Control in WCDMA 15 KHz(1500 TimsSec) Its objective is to maximize capacity by minimizing power and interference

Open Loop Power Control middot Uplink open-loop power control middot Downlink open-loop power control

Closed-loop power control Outer-loop power control

Uplink outer-loop power control Downlink outer-loop power control

Inner-loop power control Uplink inner-loop power control Downlink inner-loop power control

Open-loop power control is used to set the initial power of UE (in random access) and downlink channels The TPC commands used in inner-loop power control are relative so it needs a starting point and this is defined by open-loop power control Also this is useful in setting the power level in case of common shared channels where it is difficult to send each UE the necessary TPC commands In case of uplink UE and broadcasted cellsystem parameters are used to set initial access power on RACH And in case of downlink the measurement report of UE is used to set the initial power of downlink channelsThe open loop power control tolerance is plusmn9dB under normal conditions and plusmn12dB under extreme conditionsClosed-loop power control is the power control mechanism used in UMTS to solve near-far problem minimize interference and to keep the signal quality to optimum level Closed-loop power control is used in uplink (UL) as well as downlink (DL) However the motive in both the cases are different In uplink signals from different UEs reach NodeB with different power strength thus causing the stronger signal blocking the weaker one resulting in near-far effect In downlink there is no near-far effect but the UEs near the cell-edge or in high interference region may need extra power to overcome the increased other cell interference and weak signal due to Rayleigh fadingClosed-loop power control can be divided into outer-loop and inner-loop power control In case of uplink the RNC manages the outer-loop and Node B manages the inner-loop and for downlink UE manages the outer-loop and Node B manages the inner-loopInner-loop power control (also called fast closed-loop power control) operates at 1500 times per sec (15 kHz) [From where did this value of 15 kHz come from Answer A UMTS 10 ms frame consists of 15 TPC commands This results in a power control frequency of 1500 Hz (1510ms)] and relies on the feedback information from the opposite end of the link (or channel) to maintain the signal to interference (noise) ratio to a target level set by the outer-loop power control The transmission power is increased or decreased by a certain fixed step size depending on whether the received SIR is below or above the target SIR Precise power control can lead to optimum use of bandwidth resulting in increase cell capacity

The UL inner-loop power control lets the UE adjust its output power in accordance with one or more TPC commands received in the downlink direction Remember the increase and decrease in power is limited by upper and lower bounds as defined in 3GPP TS 25101 The upper bound ie UE maximum output power is set depending on the Power class of UE This can also be set below the maximum capability of the UE through signaling when the link is established The lower bound ie UE minimum output power defined as the mean power in one timeslot (TS) and shall be less than -50 dB

The DL inner-loop power control is used to control the transmission power of downlink channels at Node B as per the TPC commands received from UE However in some situations Node B may ignore the increasedecrease these TPC commands For example in case of congestion (high load scenario) the Node B can ignore the TPC commands from UE

Outer-loop power control is used to set the target quality value for inner-loop power control ie it adjusts the target SIR in Node B which is used during inner-loop power control Now the question is why do we need to adjust the target SIR Outer-loop power control tries to keep the quality of a connection to desired value Too high quality will waste the resources

11 What is Handover(SoftSofterHardInter-freq)Ans- Handover (Handoff)-Handover is a process in mobile communications in which a connected cellular call or a data session is transferred from one cell site (base station)to another Cell site without disconnecting

the session As a key component of the mobile communication system the cell has a limited coverage area The primary function of the handover is to provide the continuous service for the moving UEs in the coverage of the networkDifferent types of handovers have been introduced in the UMTS systemhere in WCDMA we have a few handovers

SoftSofter Handover Hard Handover Intra-System handover

Intra-frequency handover Inter-frequency handover

Inter-System handover

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Open-loop power control is used to set the initial power of UE (in random access) and downlink channels The TPC commands used in inner-loop power control are relative so it needs a starting point and this is defined by open-loop power control Also this is useful in setting the power level in case of common shared channels where it is difficult to send each UE the necessary TPC commands In case of uplink UE and broadcasted cellsystem parameters are used to set initial access power on RACH And in case of downlink the measurement report of UE is used to set the initial power of downlink channelsThe open loop power control tolerance is plusmn9dB under normal conditions and plusmn12dB under extreme conditionsClosed-loop power control is the power control mechanism used in UMTS to solve near-far problem minimize interference and to keep the signal quality to optimum level Closed-loop power control is used in uplink (UL) as well as downlink (DL) However the motive in both the cases are different In uplink signals from different UEs reach NodeB with different power strength thus causing the stronger signal blocking the weaker one resulting in near-far effect In downlink there is no near-far effect but the UEs near the cell-edge or in high interference region may need extra power to overcome the increased other cell interference and weak signal due to Rayleigh fadingClosed-loop power control can be divided into outer-loop and inner-loop power control In case of uplink the RNC manages the outer-loop and Node B manages the inner-loop and for downlink UE manages the outer-loop and Node B manages the inner-loopInner-loop power control (also called fast closed-loop power control) operates at 1500 times per sec (15 kHz) [From where did this value of 15 kHz come from Answer A UMTS 10 ms frame consists of 15 TPC commands This results in a power control frequency of 1500 Hz (1510ms)] and relies on the feedback information from the opposite end of the link (or channel) to maintain the signal to interference (noise) ratio to a target level set by the outer-loop power control The transmission power is increased or decreased by a certain fixed step size depending on whether the received SIR is below or above the target SIR Precise power control can lead to optimum use of bandwidth resulting in increase cell capacity

The UL inner-loop power control lets the UE adjust its output power in accordance with one or more TPC commands received in the downlink direction Remember the increase and decrease in power is limited by upper and lower bounds as defined in 3GPP TS 25101 The upper bound ie UE maximum output power is set depending on the Power class of UE This can also be set below the maximum capability of the UE through signaling when the link is established The lower bound ie UE minimum output power defined as the mean power in one timeslot (TS) and shall be less than -50 dB

The DL inner-loop power control is used to control the transmission power of downlink channels at Node B as per the TPC commands received from UE However in some situations Node B may ignore the increasedecrease these TPC commands For example in case of congestion (high load scenario) the Node B can ignore the TPC commands from UE

Outer-loop power control is used to set the target quality value for inner-loop power control ie it adjusts the target SIR in Node B which is used during inner-loop power control Now the question is why do we need to adjust the target SIR Outer-loop power control tries to keep the quality of a connection to desired value Too high quality will waste the resources

11 What is Handover(SoftSofterHardInter-freq)Ans- Handover (Handoff)-Handover is a process in mobile communications in which a connected cellular call or a data session is transferred from one cell site (base station)to another Cell site without disconnecting

the session As a key component of the mobile communication system the cell has a limited coverage area The primary function of the handover is to provide the continuous service for the moving UEs in the coverage of the networkDifferent types of handovers have been introduced in the UMTS systemhere in WCDMA we have a few handovers

SoftSofter Handover Hard Handover Intra-System handover

Intra-frequency handover Inter-frequency handover

Inter-System handover

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Inter-RAT handoverSofter Handover- a UE is connected to cells owned by the same NodeBa UE is connected to cells owned by the same NodeBSofter handover uplink NodeB performs maximum ratio combining ie NodeB rake receiver combines signals from different paths and forms a stronger signalSoft Handover- when a UE is connected to cells owned by different NodeB SHO is a handover in which the mobile station adds and removes radio links in such a manner that the UE (User Equipment) always keeps radio links to at least two Node Brsquos [1] During the softer handover the UE has a connection to two or more sectors of a single Node B UE continuously measures the CPICH (Common Pilot Channel) level of suitable cells and sends the results to the RNC According to this measurement RNC decides which SHO event will be activated Three events are defined addition of a cell to the Active Setreplacement of a cell and a cell removal(3dB threshold for soft handover)

The formula of Soft (Softer) Handover Success RateSoft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100 Measurement events of soft handoversofter handover Event 1A The quality of a cell reaches the quality of the best cell or active set quality thais cell add a in to the active set Event 1B The quality of a cell is far lower than the quality of the best cell itrsquos a removed a cell from active set Event 1C Replacement event A non-active primary CPICH becomes better than an active primary CPICHie replace a cell Event 1D Change of the best cell Event 1E Primary CPICH becomes better than an absolute threshold Event 1f a Primary CPICH becomes worse than an absolute threshold

Advantages- Because of the signal combination the combination gain can overcome some of the path loss During the handover UE has several RLs with the network call drop caused by ping-pong handover can be avoided Disadvantages- Soft handover will occupy more resource such as CE Iub transmission especiallyfor the code resources for BE service When the downlink power from different cells are not balanced it will cause side-effect in downlinkSoft HO FailureWhat parameters should be checkedTime To TriggerHysteresis Signal degrades too muchbut the UE doesnt a add a better cell from its monitored set Theres no active set updateSHO tuning is done mainly with Parameters like FMSC Addition Window (25 dB) FMCS Drop Window (4 dB) FMSC Addition Time (100ms) ADJS Cell Individual offset (neighbour based info) Different sets could iacutemprove the SHO performance 1) city area lot of overlappingcapacity problems- gt smaller adddrop window 2)rural area poor coverage area -gt reliable settings with cost of SHO OH rapid field drop-gt special settings 3)In Dense City area (with good CPICH EcNo levels in Active set) Small SHO overhead could be done with low AddDrop window (24 dB) In Rural areaHighways (with low CPICH EcNo ndash13hellip-16 in active set) more loose adddrop window (46 dB) could be used to have more reliability for SHO synchronisation Individual Cell Offset (ADJSEcNoOffset) value could be used for earlier SHO timing for targeted cells to avoid drop due to rapid field drop There are some settings for different clutter you can try them also For Rural Clutter Addition window-------4db(Default is 25db) Drop Window-----------6db(Default is 4db) That setting will give you More reliability time for SHO synchronization in low traffic average coverage

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

area For Urban Clutter default setting works ok For Rapid field drop you can adjust the parameter AdjsEcNoOffset (Default 0db) to -10 or +10 for locations like Gate Round-the-corner tunnel orIn case of poor HO success rate for a given adj For early cell reselection in poor coverage are you cal also modify the parameter Qhyst2 (Default value 4db) to 2dbHard Handover- HHO is a category of HO procedures in which all the old radio links of a mobile are released before the new radio links are established For real-time bearers it means a short disconnection of the bearer for non-real-time bearers HHO is losslessHard handover can take place as intra or inter frequency handover(6dB threshold for hard handover)Intra-frequency handover- in UMTS systemhard handover are possible as wellthese intra-frequency handover accurs between cells Operated within the same WCDMA carriersuch handover can be performed in UMTS networkwhen the MS is in SHO between the cells belonging to defferent radio network system Advantages- The code resources and hardware resource consumption is reduced Disadvantages- High call drop rate due to the ping-pong handover Reduced capacity compared to an ideal soft handover due to no soft handover gain Event 1D Change of best cell

Inter-frequency handover- these inter-frequency handover accurs within the cells belonging to diffaerent WCDMA Carrierssuch handover cen be completed for example handover between diffarent cells like Pico cell and micro cell Advantages-

The handover success rate is higher than that of the intra-frequency hard handover The load balance is maintained among the carriers For hierarchical cells a proper configuration of different data rates can be implemented

Disadvantages- The extra radio resources are consumed due to the compressed mode The hard handover with the re-establishment timer prolongs the handover duration and

introduces the risk of call dropsMeasurement report-Events- Event 2D The estimated quality of the currently used frequency is below a certain threshold Used to enable the compressed mode Event 2F The estimated quality of the currently used frequency is above a certain threshold Used to disable the compressed mode Event 2B The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold Used to trigger the coverage-based handover Event 2C The estimated quality of a non-used frequency is above a certain threshold Used to trigger the speed estimation inter-layer handover Inter-System handover-Inter-RAT handover-IRAT (Inter-Radio Access Technology) Inter-RAT handover refers to the handover between different systems such as UMTS and GSM which use different radio access technologies (RAT) Based on handover directions inter-RAT handover is of two types

UMTS-gtGSM handover (mainly described in this lecture) GSM-gtUMTS handover

Based on triggering causes UMTS-gtGSM handover includes UMTS-gtGSM coverage-based handover UMTS-gtGSM load-based handover

UMTS-gtGSM coverage-based handover The coverage of UMTS is discontinuous at the very beginning On the border if the signal quality of UMTS rather than GSM is poor and if all services of the UE are supported by GSM UMTS-gtGSM coverage-based handover is triggered The CPICH EcN0 or CPICH RSCP of the UMTS cell to which the UE connects is lower than the corresponding threshold In addition there is a GSM cell whose GSM carrier RSSI is higher than the preset thresholdUMTS-gtGSM load-based handover - If the load of UMTS rather than GSM is heavy and all services of the UE are supported by GSM UMTS-gtGSM load-based handover is triggered The load of the UMTS cell to which the UE connects is higher than the threshold

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

2D Event When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurement (initiate GSM measurement)2F Event When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurement( stop GSM measurement)3A Event When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on coverage (based on coverage)3C Event When the signal quality of any other system is higher than the preset threshold the RNC triggers UMTS-gtGSM handover based on load or service (based on non-coverage)

Advantages- Coverage solve the transition between different RATs Capacity leverage the existing equipment to a maximum extent (2G-gt3G)

Disadvantages- The procedure is complex and has the high requirements on the equipment compatibility

The UE is complex18What is Compressed modewhy we Need Ans-When Radio Condition is poor below thrisholed value RSCP-92dBmEcIo-12dBThe compressed mode includes two types spreading factor reduction (SF2) and high layer approachesThe usage of type of compressed mode is decided by the RNC automatically according to spreading factor used in uplink or downlink then Sf2 is used to send the data to reduise the time of transmiting the signal in the remaining time Ue Sened 2G or 4G frequency and send the messurment report to RNC Event 2D- When the signal quality of the currently used frequency is lower than the preset threshold the RNC enables the compressed mode and starts inter-RAT measurementEvent 2F- When the signal quality of the currently used frequency is higher than the preset threshold the RNC disables the compressed mode and stops inter-RAT measurementCompressed Mode ParameterTGSN (Transmission Gap Starting Slot Number) A transmission gap pattern begins in a radio frame called firstradio frame of the transmission gap pattern containing at least one transmission gap slot TGSN is the slot numberof the first transmission gap slot within the first radio frame of the transmission gap patternbull TGL1 (Transmission Gap Length 1) Duration of the first transmission gap within the transmission gap pattern expressed in number of slotsbull TGL2 (Transmission Gap Length 2) Duration of the second transmission gap within the transmission gap pattern expressed in number of slots If this parameter is not explicitly set by higher layers then TGL2 =TGL1bull TGD (Transmission Gap Start Distance) Duration between the starting slots of two consecutive transmission gaps within a transmission gap pattern expressed in number of slots The resulting position of the second transmission gap within its radio frame(s) shall comply with the limitations of TS 25101 (Ref [2]) If this parameter is not set by higher layers then there is only one transmission gap in the transmission gap patternbull TGPL1 (Transmission Gap Pattern Length) Duration of transmission gap pattern 1bull TGPL2 (Transmission Gap Pattern Length) Duration of transmission gap pattern 2 If this parameter is not explicitly set by higher layers then TGPL2 = TGPL1The following two parameters (integers) control the transmission gap pattern sequence start and repetitionbull TGPRC (Transmission Gap Pattern Repetition Count) Number of transmission gap patterns within the transmission gap pattern sequence From Figure 10 it seems TGPRC is even therefore the number of slots in TG Sequence is 05TGPRC (TGPL1+TGPL2)bull TGCFN (Transmission Gap Connection Frame Number) CFN of the first radio frame of the first pattern 1 within the transmission gap pattern sequence

14 What are the conditions you typically set to trigger IRAT handoverAns-RSCP and EcIo are used to trigger IRAT handoverRSCP le -100dBmEcIo le -16dBm

Why do I need a Scanner 50x higher performance than test mobiles can deliver Independent to the network Hidden neighborhoods

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Pilot Pollution and interference causes are not detectable Spectrum analysis provides a detection of external interferences Independent of mobile chipsets ndashgt reference Higher level and time accuracy compared to mobile based measurements Use of only one unit for different networks and applications No costs and no capacity will be allocated Cheaper compared to many band-dedicated units

17what is the SSV DriveampClluster Drive in WcdmaAns-WCDMA RNO Single Site Verification(SSV-Drive test) Through the single site verification check whether the following functions in each cell are proper

Configuration data collection(From Planner) Site installation check (Ensure that the feeder is connected properly) Site state and alarm check Parameter configuration check in idleampDed mode Objectivity scrambling code frequency and LACRAC Call check in connection mode(VoiceVedioR99HSDPASMSall Services) Coverage check (CPICH RSCP amp CPICH EcIo) Handovers SoftsofterHard Handovers check

Before the site check collect the configuration data of network planning and other data in RNC database and ensure that the configured data is consistent with the planned onewhen visited the site need to check the site installation type as per planned like (heightazimuthtits) ofter thet Before the site verification the optimization engineers need to confirm with the product support engineers whether the alarm is generated whether problems are solved and whether cell state is proper Check whether the cell configuration data is consistent with the planned one by the UEScanner such as NODEBNAMELOCELL ID MAXTXPOWER LAC

RACPSC CODE and UARFCNDOWNLINK Azimuthtilts

Drive Test contents- Through the drive test need to check all services UEScanner (VoiceVideoFtpHSDPASMS) in wach sector or cell the test point should be near the center of the cell with line-of-sight distance to the NodeB In this way better coverage and little signal fluctuation are implemented For a macro cell the test spot should be less than 100 m from the NodeB in the direction of major beam of cell antenna with line-of-sight distance to

the NodeB The test spot should not locate right under the NodeB because other sectors in the same NodeB also have strong signals which cannot ensure that the test is performed in the cell to be measured The test spot is determined by observing CPICH RSCP measured by the ScannerAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up FailuresInterfarancePoilat Poluction and resolve these problems) For 3G Service Check the following tests will be considered 3G short and Long callVideo callSMSR99 FTP downloadHSDPA amp HSUPA FTP transfer

15 What are the typical KPIs in WCDMAAns-WCDMA RAN Key Performance Indicators

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Accessibility- RRC setup procedure-

UE SRNCNodeB

RRC RRCRRC Connection Request

RRC

RRC

Assign RNTI L1 L2 Parameter

RRC

AAL2 Setup and FP synchronization

RRC Connection Setup

RRCRRC Connection Setup Complete

The formula of RRC Setup Success Rate RRC Setup Success Rate = RRC Connection Setup Success RRC Connection Request times 100We shood maintain the KIP

PERF ITEM GOOD NORMAL BADRRC Setup Success Rate gt98 gt=95 lt95

Possible failure UE does not receive the RRC setup message from RNC RNC does not receive the RRC setup complete message RRC rejected due to congestion

Possible reason- BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

RAB setup success ratio- RAB setup procedure （DCH-DCH synchronized）UE SRNCNodeB CN

RANAP RANAPRAB Assignment Request

ALCAP Iu Data Transport Bearer Setup

RRCRRC

RRC

RB Setup

RRCRB Setup Complete

RANAP RANAPRAB Assignment Response

NBAP RRCRL Reconfig Prepare

NBAP NBAP

NBAP NBAP

ALCAP Iub Data Transport Bearer Setup

RL Reconfig Ready

RL Reconfig Commit

Perf Item Good Normal BadAMR RAB Assignment Success Rate [] gt98 gt=95 lt95

Video Call RAB Assignment Success Rate [] gt98 gt=95 lt95

PS RAB Assignment Success Rate [] gt98 gt=95 lt95

Possible failure CN send RAB assignment Req but UE does not receive RB setup message UE receives RB Setup but RNC does not receive RB setup complete

Possible reason BAD RF Condition Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call drop ratio Call Drop Rate of Signaling Plane is calculated by counting RNC-originated Iu connection release Can be divided into two parts CSampPS

The formula of Call Drop Rate of CS Signaling Plane Call Drop Rate of CS Signaling Plane = RNC-originated CS Domain Iu Connection Release RNC-originated CS Domain Iu Connection Setup Successtimes 100

The formula of Call Drop Rate of PS Signaling Plane Call Drop Rate of PS Signaling Plane = RNC-originated PS Domain Iu Connection Release RNC- originated PS Domain Iu Connection Setup Successtimes 100We shood maintain the KPI

PERF ITEM GOOD NORMAL BAD

CS AMR CALL DROP RATE() lt1 lt=2 gt2

VP CALL DROP RATE() lt1 lt=2 gt2

PS SERVICE DROP RATE() lt1 lt=3 gt3

HSDPA SERVICE DROP RATE() lt1 lt=3 gt3

HSUPA SERVICE DROP RATE lt1 lt=3 gt3 Possible causes

BAD RF Condition

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

Sites Overshooting Interference pilot polution EcIo is poor Transmission packet loss Hardware alarm

Call Drop Due to Neighbor Cell Missing- Generally the call drop is caused by neighbor cell missing during the early phase of optimization For the intra-frequency neighbor cells you can use the following methods to determine whether the call drop is caused by intra-frequency neighbor cell missingMethod 1 Check the EcIo information about cells in the active set recorded by the UE and the Best Server EcIo information recorded by the Scanner If the EcIo recorded by the UE is poor and the Best Server EcIo recorded by the Scanner is good check whether the Best Server scrambling code recorded by the Scanner is included in the intra-frequency measurement control If the scrambling code is not included you can infer that the call drop is caused by the neighbor cell missing Method 2 If the UE reconnects to the network immediately after the call drop and the cell scrambling code used during the reconnection of the UE is inconsistent with that used during the call drop the call drop may be caused by the neighbor cell missing You can confirm the cause through the measurement control The neighbor cell missing including the inter-frequency neighbor cell missing and the inter-RAT neighbor cell

missing can result in call drop Method 3 Adopt the Nastar neighbor cell analysis function to check whether the neighbor cell missing problem existsMethod 4 Enable the measurement analysis detection set (RNC detection set) to report 1A event

Call Drop Due to Coverage Problem- Generally poor coverage implies that both the RSCP and EcIo are poor You can confirm the coverage problem by checking the transmit power of uplinkdownlink special channels through the following methods If the uplink transmit power reaches the maximum value before the call drop and the uplink BLER is poor or the single user tracing recorded by the RNC suggests that Node B reports RL failure you may infer that the call drop is caused by poor uplink coverage If the downlink transmit power reaches the maximum value before the call drop and the downlink BLER is poor you may infer that the call drop is caused by poor downlink coverage You can also confirm the coverage problem through the following simple and direct methodCheck the data collected by the Scanner If both the RSCP and EcNo of the best cell are poor you can determine that the poor coverage results in the call drop

Call Drop Due to Handoff Problem- There are two reasons for the call drop caused by the soft handoffinter-frequency that is it is too late to perform the handoff or ping-pong handoff In terms of the signaling process for the CS service the UE does not receive the active set update command for the PS service the TRB is reset before the handoff of the UEIn terms of signal there are two scenarios in which it is too late for the handoff(1) Corner The EcIo of the source cell has a sudden sharp drop and the EcNo of the target cell has an

unexpected dramatic increase (2) Pinpoint The EcIo of the source cell increases after a period of time in rapid fall The EcIo of the target

cell has a sudden increase in a short time periodThe ping-pong handoff involves the following cases

(1) The primary cell changes rapidly Two or more cells take turns to be the primary cell The primary cell has better RSCP and EcIo and exists in a short period of time (2) There are multiple secondary cells The RSCP is normal and there is slight difference between RSCPs of cells The EcIo in each cell is poor

Call Drop Due to Interference Problem- For the downlink if the CPICH RSCP is greater than -85 dB and the EcIo is smaller than -13 dB the call drop tends to occur This may be caused by downlink interferenceFor the uplink if the RTWP is 10 dB greater than the normal value (-104 to -105) there may be a call drop This is caused by pilot pollution

Missing neighbor Problem description The drop occurs when the signal quality is bad on the Best Serving cell with the possibility for the UE to perform a SHO on a better cell that is not declared as a Neighbor The Active Set best

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

server is cell of SC= 248 During the call cell of SC = 464 becomes the strongest cell but is not added tothe active set as it is not defined as neighboring cell (Figure 211) The cell of SC =464 acts as an increasing interferer until eventually the call is released

SHO success ratio The formula of Soft (Softer) Handover Success Rate Soft (Softer) Handover Success Rate = Soft (Softer) Handover Success Soft (Softer) Handover Requesttimes 100

When the UE handles the ACTIVE SET UPDATE message the abnormal cases may be occurred and the UE shall transmit an ACTIVE SET UPDATE FAILURE message with the following failure causes

Configuration unsupported Incompatible simultaneous reconfiguration Protocol error Invalid configuration

If the time expired before RNC receives the message ACTIVE SET UPDATE COMPLETE or ACTIVE SET UPDATE FAILURE from UERNC increases the SHO failure counter with the following cause No response from UE We shood maintan the KPI

6 What are the major differences between GSM and UMTS handover decisionGSMTime-based mobile measures of RxLev and RxQual ndash mobile sends measurement report every SACH period (480ms)BSC instructs mobile to handover based on these reportsUMTSEvent-triggered reporting ndash UE sends a measurement report only on certain event ldquotriggersrdquoUE plays more part in the handover decision10 What can we try to improve when access failure is highWhen access failure is high we can try the following to improve RACH performanceIncrease maximum UE transmit power allowed Max_allowed_UL_TX_PowerIncrease power quickly power_Offset_P0Increase number of preambles sent in a given preamble cycle preamble_Retrans_MaxIncrease the number of preamble cycles max_Preamble_CycleIncrease number of RRC Connection Request retries N300In 1 call 20times preambles we can sent if need we can increase 35 How to Calculate Max Numbers of Users in CellAns- W chip rate (for UMTS 3840000 chips per second)EbNo EbNo requirement (assuming 3dB for CS-122k)i other-cell to in-cell interference ratio (assuming 60)R user data rate (assuming 12200 kbps for CS-122k)η loading factor (assuming 50)

Take 122kbps as exampleM = W (EnNo (1 + i) R) η = 3840000 (3 (1 + 06) 12200) 05 = 328

The number of users could also be hard-limited by OVSF code space Take CS122k for examplebull A CS-122k bearer needs 1 SF128 codebull Total available codes for CS-122k = 128 ndash 2 (1 SF64) ndash 2 (4 SF256) = 124bull Consider soft-handover factor of 18 and loading factor of 50 124 18 05 = 34 userscell49 How many slots are there in a WCDMA Frame How big is a frame in ms how many chips are there in a slot

WCDMA Frame is 15 slots wide It is 10ms in length There are 2560 chips in one slot Chip rate is 3840 KcsLength of frame = 10 msNumber of chips in a frame = 3840 10=38400 chipsNumber of chips in a slot = 3840015= 2560 chipsHow much power usually a Node B is allocated to control channelsThe power allocated to control channels may depend on equipment vendor recommendation Typically no more than 20 of the total NodeB power is allocated to control channels including CPICH However if HSDPA is deployed on the same carrier then the total power allocated to control channel may go up to 25 to 30 because of the additional HSDPA control channels required65 When is System information sent to UEAns- The system information is regularly broadcast to the UE on the BCCH When a parameter in the system information is changed all UE in a cell are notified by a paging message or by a system information change indication message77 What is a typical UE sensitivity levelAns- The service and load determines the UE sensitivity in general in no-load condition the sensitivity is between -105dBm and -120dBm For Ericsson the UE sensitivity level is calculated at aroundCS122 -119 dBm PS-64 -112 dBmPS-128 -110 dBm PS-384 -105 dBmHSDPA -95 dBm78 What is a typical NodeB sensitivity levelThe service and load determines the NodeB sensitivity in general in a no-load condition the sensitivity is between -115dBm to -125dBm For Ericsson the NodeB sensitivitylevel is calculated at aroundCS122 -124 dBm PS-64 -119 dBmPS-128 -115 dBm PS-384 -115 dBm79 W hat is a typical NodeB maximum output power-UMTSAns- The maximum NodeB output power is usually 20W or 40W that is 43dBm or 46dBmAlso upto 100WSIB(System Information Block) and their Detailssystem information block is multiplexed with synchronization channel Synchronization channel occupies the first time slot (TS) and SIB occupies the other 9 time slotsSIB1 NAS Information UE Timers and counters to be used in RRC Idle amp Connected StateSIB2 List of URA IdentitiesSIB3 Parameters for Cell Selection and ReselectionSIB4 Same as SIB3 but used in Connected StateSIB5 Configuration parameters of common physical channels in a cell PCH and PICH Info (CPCH)SIB6 Configuration of Common and Shared physical channelSIB7 Contains fast changing UL interface params and dynamic As this is changes often so controlled by timerSIB8 Used in FDD Static CPCH info of cell Used in Connected mode onlySIB9 CPCH info As it changed often controlled by timers connected mode onlySIB10 DRAC Procedure used when CELL_DCH controlled by timerSIB11 Measurement control information to be used in CELLSIB12 Same as SIB11 but used in connected mode onlySIB13 For ANSI-41 It also has 4 associated SIBS 131 to 134 Reference to subblocks Used when System is ANSI-41SIB14 Parameters for common and dedicated physicall DPCH UL outer loop power control info for TDDSIB15 Assistance info for UE positioning Used to reduce signalling by position 151 to 155 sub sibsSIB16 Predefined channel conf used while hand over Radio Bearer transport channel physical channel params to be stored by UE in idleconnected mode Several occurances but UE doesnot botherSIB17 Shared channel info fo rTDD onlySIB18 PLMN Identities of neighbouring cells Used in Shared Access Nw with the cell reselection process If my MS is on Video Call amp it takes Handover from UMTS Cell to GSM Cell So would my Video Call Services

Terminated or Converted to circuit switch speech call As far I am concern I believe that After handover to GSM The video call will stop Bcoz there UMTS is a separete technology and hence GSM will not support the RAB assignment process used for data ratesOnly the speech will go to GSM as an Speech voice call Bcoz the The Video call is an CS data call hence it vant go the GPRS with low data ratesIn my opinion if handover between UMTS and GSM is successful and if there is HSCSD feature enabled as the pooltype on the target cell voice call will continue although it will be useless to use due to insufficient data speedThe speed of the transfer itself is not a parameter for a call dropso the voice call cant be dropped as long as there is HSCSD enabled and sufficient TCH on A interface Voice call would be mainained in either caseHow to increase CS traffic usage on 3G with Huawei equipment1) Make Mobile cell reselection more easily from 2G to 3G check the below parameters qsearch_i normally set to 7 (always search 3G in 2G idle mode) qsearch_C_Initial 0-use qsearch_i to decide 1-always search fdd_qoffset decide how many DBs the 3G cell should above or below 2G cell for cell reselection fdd_rep_quant decide Mobile measure CPICPs RSCP or EcNo 0 for RSCP 1 - EcNo fdd_multirat_reporting Number of 3G cells should be reported in the measurement report fdd_qmin decide how much the target 3G cells EcNo should be above this threshold when MS does cell reselection to 3G What is 3GPPThe Connectivity Packet Platform (CPP) comprises a multiprocessor control system using commercially available processors functionality for element management and an ATM transport system The Connectivity Packet Platform consists of modules including both software(such as programs that set up connections and modify operating parameters) and hardware (such as processor boards switch boards and backplaneconnectors)CPP is a platform from which it is possible to develop an ATM Cell Switching network node for example a simple ATM switch or a AAL2 switching node or an RBS or an RNC Connectivity Packet Platform provides most of The transport network layer functionality required for the WCDMA RAN applicationWhat is Release 99Release 99Bearer services64 kbits circuit switch384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Voice quality features - Tandem Free OperationWhat is HSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3GPP Release 5 feature that provides data-related enhancements on top of WCDMA Rel 99 functionalities HSDPA offers higher data rates for end-users and larger capacity in the radio network HSDPA uses the High-Speed Downlink Shared Channel (HS-DSCH) channel in the RNC Signal processing for HS-DSCH channel includes FP ciphering and MAC functionsWhat is Control PlaneThe radio network protocol for control plane is called Radio Access Network Application Protocol (RANAP)and is used towards both the MSC node and the SGSN node One RNC is connected to up to two Core Network parts per UE connection using RANAP signaling carried on SCCP for ATM and SCTP for IPNo connection when the RNC acts as a DRNC one or two when the RNC acts as an SRNC (circuit andor packet switched part)What is User Plane Two main types of User plane bearers are provided over the Iubull Towards the circuit switched Core Network for voice or Circuit Switched Data using AAL2 connectionsbull Towards the packet Core Network for IP traffic using packet tunneling over Iu by the GTP-U protocol carried by UDPIP This is carried over AAL5 when ATM is used One UE connection may be involved in both types of Radio Access Bearers The Iu interface supports a userWhat is MDC(Macro Diversity Combining) application Macrodiversity Combining is done during soft handover that is separate radio channels (from different base stations) are combined to one channel in the RNC in order to achieve maximum obtainable quality Soft handover is applicable for all Dedicated Channels (DCH) DCHs can be used for user traffic and signaling The Macrodiversity

Combining (MDC) application handles the combining and splitting of the Media Access Control (MAC) frames arriving to the serving RNC from the IubIur interface during a soft handover The main functions offered by the MDC feature arebull Iu User Plane protocol towards the core network (CN)bull Radio Link Control (RLC) layer for RT databull ciphering of the RLCMAC PDUsbull Media Access Control (MAC) layer for dedicated channelsbull macrodiversity combining and splitting of the MAC framesbull Frame Protocol (FP) layer for Iub and Iur interfacesbull outer loop Power Control (PC) supportMacrodiversity Combining application is used in the Radio Network Controller (RNC)network elementWhat is RLC layer does Radio Link Control protocolThe RLC protocol implementation supports 3GPP Release 4 features transparent mode For transparent data transfer service the application supports segmentation and reassembly and transfer of user data functionsThe application also provides QoS setting and notification of unrecoverable errorsWhat is CipheringCiphering is always performed in the serving RNC Signalling procedures required for ciphering mode setting involve RANAP and RRC signalling for radio access bearer (RAB) parameter managementThe ciphering function is performed either in the RLC sub-layer or in the MAC sub-layeraccording to the following rulesbull If a radio bearer is using a non-transparent RLC mode (AM or UM) ciphering is performedin the RLC sub-layer Ciphering is performed on Payload Unit (PU) basisbull If a radio bearer is using the transparent RLC mode ciphering is performed in theMAC sub-layer (MAC-d entity)bull Only DTCH and DCCH channels are encryptedWhat is Power Control in RNCThe target of the power control (PC) is to achieve the minimum signal-to-interferenceratio (SIR target) that is required for the sufficient quality of the connectionWhat is Iu InterfaceThe Iu is the interface between the Core Network and WCDMA RAN moreprecisely between the RNC node and the different domains of Core Network The terms Iu-CS and Iu-PS are used to indicate associations to thecircuit switched network and the packet switched network respectively The term Iu-BC is used to indicate association to broadcast of unacknowledged messagesbull the Circuit Switched domain Iu-CS to MSC server (RANAP) and MGw (Iu User Plane)bull the Packet Switched domain Iu-PS to the SGSNbull the Broadcast domain Iu-BC from the Cell Broadcast Center (CBC) The Iu interface is an open standardized interface providing multi-vendorequipment to be supplied for both the Core Network and the WCDMA RAN

What is Iur InterfaceThe Iur interface is a WCDMA internal interface for the communication between two RNC nodes (and between two RNSs) It is an open and standardized interface The interface contains a control plane for radio signaling and AAL2 connection establishment and a user plane supporting guaranteed QoS on ATM or IP Notethat all ATM user plane traffic is carried on the same type of AAL2 connection packet data voice and Unrestricted Digital Information (UDI)159)What is HSUPAHSUPA stands for High Speed Uplink Packet Access and improves the uplink performance in networks which support HSUPA 3G networks support a maximum of 384kbps on the uplink HSUPA will support a maximum of 19Mbps The average uplink speed will be about 1Mbps160)Do 35GHSPA networks support VoiceHSPA is purely a data network All Voice traffic is supported on the current 3G network161)What are the benefits of using 35GHSPA for the end-userAs a result of the enhancement 35GHSPA promises a better broadband multimedia experience For the business user HSDPA enables high-speed Internet access and rapid download of emails with attachments For the consumers HSDPA allows faster downloading of high-resolution digital images high-quality music downloads Mobile TV and mobile multi-player games162)What do I need to enjoy the enhanced experience using 35GHSPA

To enjoy 35GHSPA services you will require a HSDPA-enabled phone and a 3G USIM163)What is the maximum download speed of StarHubs 35GHSPA networkStarHubs 35GHSPA network currently supports download speeds of up to 21Mbps and upload speeds of up to 576Mbps(Note Actual bandwidth and speeds experienced are dependent on a combination of factors including the mobile equipment software used internet traffic and destination server Presently only the Mobile Broadband Modem supports up to 21Mbps (download) and up to 576Mbps (upload) Most handsets available today only supports HSDPA with download speeds of up to 36Mbps and upload speeds of 384kbps)164)What affects the download and upload speeds when using the HSPA serviceAs with any network the actual bandwidth experienced will have to take into account network and protocol overheads and therefore the actual addressable bandwidth might be lower In addition to this performance will also be affected by the following the mobile equipment that you are using and the bandwidth it supports the websites and servers you are accessingthe types of Applications being used the radio conditions level of congestion on the InternetHSDPA in W-CDMAHigh Speed Downlink Packet Access (HSDPA) is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbps (and 20 Mbps for MIMO systems) over a 5MHz bandwidth in WCDMA downlink HSDPA implementations includes Adaptive Modulation and Coding (AMC) Multiple-Input Multiple-Output (MIMO) Hybrid Automatic Request (HARQ) fast cell search and advanced receiver designIn 3rd generation partnership project (3GPP) standards Release 4 specifications provide efficient IP support enabling provision of services through an all-IP core network and Release 5 specifications focus on HSDPA to provide data rates up to approximately 10 Mbps to support packet-based multimedia services MIMO systems are the work item in Release 6 specifications which will support even higher data transmission rates up to 20 Mbps HSDPA is evolved from and backward compatible with Release 99 WCDMA systems Currently (2002) 3GPP is undertaking a feasibility study on high-speed downlink packet access

What is benefit of shorter TTI in HSDPA1)After every TTI the resources can be redistributed among the users Therefore the resource usage is more efficient2)each UE reports about the channel quality after every TTI by sending the CQI3)CQI is sent after the very short period of time of 2 ms it is possible to effectively perform link adaptation even in rapidly changing conditions What is Latency in HSDPALatency is the time a packet needs to travel from sender to receiver While UMTS typically features an end-to-end latency of approximately 200ms HSDPA manages to lower the delay times in transmission to around 100ms What is Link AdaptionHSDPA uses link adaptation which means the way of transmission is changed according to the quality of the channel If a user is in favourable conditions for example close to the nearest antenna tower this user will be assigned a high data rateWhen the user moves into worse channel conditions for example far away from the antenna tower the transmission parameters will be changed accordingly and thus the data rate will be decreased

130) How power control is implemented in HSDPAAns- Initial power is set in the same way as open loop power control of DCH amp there is no further power control on HSDPA shared channel HS-DSCHThe channel rate is controlled by adaptive modulation amp coding formatThe principle amp functionality of the power control for the HSDPA associated dedicated channels are the same as for the DPCH power controlHS-DPCCH power is an offset relative to DPCCH depending upon whether the UE is in soft handoff or not The power of HS-SCCH is fixed125) What is Multiple PDP and what is meant by Multi RAB and multi call2 PS - Multiple PDPPS+CS ndash Multi RAB2CS ndash Multi Call110) What is Channelisation scramblingSpreading is applied to the Physical Channels (except SCH) It consists of two distinct operations a Channelisation and b Scrambling Channelisation is performed before scramblingChannelisationThe term spreading is also used to refer to channelisation Channelisation is the basis for Code Division Multiple Access (CDMA) encoding This operation transforms every data symbol of a signal into a number of chips The bandwidth of the resulting signal occupies a much larger bandwidth typically 5 MGHz and therefore the name Wideband-CDMA or W-CDMAThe number of chips per data

symbol is called the Spreading Factor (SF)Scrambling108) Features of Rel99Rel5Rel67 Release 99Release 99Bearer services64 kbits circuit switched384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Release 5 ndash 2002 High Speed Downlink Packet Access (HSDPA)

HSDPA Basic Concepts1)In HSDPA a common channel with fixed power is employed for data transfer Users are separated in both the time and code domains A fixed spreading factor is employed but multi codes operation is possible for increased data rates 2)Adaptive Modulation and Coding (AMC) replaces the role of power control so that the modulation and coding rate are changed depending on the channel condition 3)This is accomplished by locating the scheduling algorithm for channel allocation at the Node B instead of the RNC in Release 99

Drive Test and Radio-optimization for UMTSGSM Networks Introduction _ Site verification of radio parameters _ Network performance checking in static positions _ Network performance checking in mobile positions _ Area Drive test verification _ Drive test analysis amp recommendations _ Case Studies

Our company specialized in radio telecommunication puts under your disposition our skills and experiences concerning Site verification radio parameters - Drive test data - Analysis and recommendations in order to optimize the performance of our networkWe perform testing for 2G and 3G networks (GSMGPRSEDGE UMTSR99HSDPAHSUPA)

Preparation for DT (drive test) Hardware

Test phone Scanner GPS

Software Drive test software for example GENEX Probe Drive test post process software for example GENEX Assistant

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Terminated or Converted to circuit switch speech call As far I am concern I believe that After handover to GSM The video call will stop Bcoz there UMTS is a separete technology and hence GSM will not support the RAB assignment process used for data ratesOnly the speech will go to GSM as an Speech voice call Bcoz the The Video call is an CS data call hence it vant go the GPRS with low data ratesIn my opinion if handover between UMTS and GSM is successful and if there is HSCSD feature enabled as the pooltype on the target cell voice call will continue although it will be useless to use due to insufficient data speedThe speed of the transfer itself is not a parameter for a call dropso the voice call cant be dropped as long as there is HSCSD enabled and sufficient TCH on A interface Voice call would be mainained in either caseHow to increase CS traffic usage on 3G with Huawei equipment1) Make Mobile cell reselection more easily from 2G to 3G check the below parameters qsearch_i normally set to 7 (always search 3G in 2G idle mode) qsearch_C_Initial 0-use qsearch_i to decide 1-always search fdd_qoffset decide how many DBs the 3G cell should above or below 2G cell for cell reselection fdd_rep_quant decide Mobile measure CPICPs RSCP or EcNo 0 for RSCP 1 - EcNo fdd_multirat_reporting Number of 3G cells should be reported in the measurement report fdd_qmin decide how much the target 3G cells EcNo should be above this threshold when MS does cell reselection to 3G What is 3GPPThe Connectivity Packet Platform (CPP) comprises a multiprocessor control system using commercially available processors functionality for element management and an ATM transport system The Connectivity Packet Platform consists of modules including both software(such as programs that set up connections and modify operating parameters) and hardware (such as processor boards switch boards and backplaneconnectors)CPP is a platform from which it is possible to develop an ATM Cell Switching network node for example a simple ATM switch or a AAL2 switching node or an RBS or an RNC Connectivity Packet Platform provides most of The transport network layer functionality required for the WCDMA RAN applicationWhat is Release 99Release 99Bearer services64 kbits circuit switch384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Voice quality features - Tandem Free OperationWhat is HSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3GPP Release 5 feature that provides data-related enhancements on top of WCDMA Rel 99 functionalities HSDPA offers higher data rates for end-users and larger capacity in the radio network HSDPA uses the High-Speed Downlink Shared Channel (HS-DSCH) channel in the RNC Signal processing for HS-DSCH channel includes FP ciphering and MAC functionsWhat is Control PlaneThe radio network protocol for control plane is called Radio Access Network Application Protocol (RANAP)and is used towards both the MSC node and the SGSN node One RNC is connected to up to two Core Network parts per UE connection using RANAP signaling carried on SCCP for ATM and SCTP for IPNo connection when the RNC acts as a DRNC one or two when the RNC acts as an SRNC (circuit andor packet switched part)What is User Plane Two main types of User plane bearers are provided over the Iubull Towards the circuit switched Core Network for voice or Circuit Switched Data using AAL2 connectionsbull Towards the packet Core Network for IP traffic using packet tunneling over Iu by the GTP-U protocol carried by UDPIP This is carried over AAL5 when ATM is used One UE connection may be involved in both types of Radio Access Bearers The Iu interface supports a userWhat is MDC(Macro Diversity Combining) application Macrodiversity Combining is done during soft handover that is separate radio channels (from different base stations) are combined to one channel in the RNC in order to achieve maximum obtainable quality Soft handover is applicable for all Dedicated Channels (DCH) DCHs can be used for user traffic and signaling The Macrodiversity

Combining (MDC) application handles the combining and splitting of the Media Access Control (MAC) frames arriving to the serving RNC from the IubIur interface during a soft handover The main functions offered by the MDC feature arebull Iu User Plane protocol towards the core network (CN)bull Radio Link Control (RLC) layer for RT databull ciphering of the RLCMAC PDUsbull Media Access Control (MAC) layer for dedicated channelsbull macrodiversity combining and splitting of the MAC framesbull Frame Protocol (FP) layer for Iub and Iur interfacesbull outer loop Power Control (PC) supportMacrodiversity Combining application is used in the Radio Network Controller (RNC)network elementWhat is RLC layer does Radio Link Control protocolThe RLC protocol implementation supports 3GPP Release 4 features transparent mode For transparent data transfer service the application supports segmentation and reassembly and transfer of user data functionsThe application also provides QoS setting and notification of unrecoverable errorsWhat is CipheringCiphering is always performed in the serving RNC Signalling procedures required for ciphering mode setting involve RANAP and RRC signalling for radio access bearer (RAB) parameter managementThe ciphering function is performed either in the RLC sub-layer or in the MAC sub-layeraccording to the following rulesbull If a radio bearer is using a non-transparent RLC mode (AM or UM) ciphering is performedin the RLC sub-layer Ciphering is performed on Payload Unit (PU) basisbull If a radio bearer is using the transparent RLC mode ciphering is performed in theMAC sub-layer (MAC-d entity)bull Only DTCH and DCCH channels are encryptedWhat is Power Control in RNCThe target of the power control (PC) is to achieve the minimum signal-to-interferenceratio (SIR target) that is required for the sufficient quality of the connectionWhat is Iu InterfaceThe Iu is the interface between the Core Network and WCDMA RAN moreprecisely between the RNC node and the different domains of Core Network The terms Iu-CS and Iu-PS are used to indicate associations to thecircuit switched network and the packet switched network respectively The term Iu-BC is used to indicate association to broadcast of unacknowledged messagesbull the Circuit Switched domain Iu-CS to MSC server (RANAP) and MGw (Iu User Plane)bull the Packet Switched domain Iu-PS to the SGSNbull the Broadcast domain Iu-BC from the Cell Broadcast Center (CBC) The Iu interface is an open standardized interface providing multi-vendorequipment to be supplied for both the Core Network and the WCDMA RAN

What is Iur InterfaceThe Iur interface is a WCDMA internal interface for the communication between two RNC nodes (and between two RNSs) It is an open and standardized interface The interface contains a control plane for radio signaling and AAL2 connection establishment and a user plane supporting guaranteed QoS on ATM or IP Notethat all ATM user plane traffic is carried on the same type of AAL2 connection packet data voice and Unrestricted Digital Information (UDI)159)What is HSUPAHSUPA stands for High Speed Uplink Packet Access and improves the uplink performance in networks which support HSUPA 3G networks support a maximum of 384kbps on the uplink HSUPA will support a maximum of 19Mbps The average uplink speed will be about 1Mbps160)Do 35GHSPA networks support VoiceHSPA is purely a data network All Voice traffic is supported on the current 3G network161)What are the benefits of using 35GHSPA for the end-userAs a result of the enhancement 35GHSPA promises a better broadband multimedia experience For the business user HSDPA enables high-speed Internet access and rapid download of emails with attachments For the consumers HSDPA allows faster downloading of high-resolution digital images high-quality music downloads Mobile TV and mobile multi-player games162)What do I need to enjoy the enhanced experience using 35GHSPA

To enjoy 35GHSPA services you will require a HSDPA-enabled phone and a 3G USIM163)What is the maximum download speed of StarHubs 35GHSPA networkStarHubs 35GHSPA network currently supports download speeds of up to 21Mbps and upload speeds of up to 576Mbps(Note Actual bandwidth and speeds experienced are dependent on a combination of factors including the mobile equipment software used internet traffic and destination server Presently only the Mobile Broadband Modem supports up to 21Mbps (download) and up to 576Mbps (upload) Most handsets available today only supports HSDPA with download speeds of up to 36Mbps and upload speeds of 384kbps)164)What affects the download and upload speeds when using the HSPA serviceAs with any network the actual bandwidth experienced will have to take into account network and protocol overheads and therefore the actual addressable bandwidth might be lower In addition to this performance will also be affected by the following the mobile equipment that you are using and the bandwidth it supports the websites and servers you are accessingthe types of Applications being used the radio conditions level of congestion on the InternetHSDPA in W-CDMAHigh Speed Downlink Packet Access (HSDPA) is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbps (and 20 Mbps for MIMO systems) over a 5MHz bandwidth in WCDMA downlink HSDPA implementations includes Adaptive Modulation and Coding (AMC) Multiple-Input Multiple-Output (MIMO) Hybrid Automatic Request (HARQ) fast cell search and advanced receiver designIn 3rd generation partnership project (3GPP) standards Release 4 specifications provide efficient IP support enabling provision of services through an all-IP core network and Release 5 specifications focus on HSDPA to provide data rates up to approximately 10 Mbps to support packet-based multimedia services MIMO systems are the work item in Release 6 specifications which will support even higher data transmission rates up to 20 Mbps HSDPA is evolved from and backward compatible with Release 99 WCDMA systems Currently (2002) 3GPP is undertaking a feasibility study on high-speed downlink packet access

What is benefit of shorter TTI in HSDPA1)After every TTI the resources can be redistributed among the users Therefore the resource usage is more efficient2)each UE reports about the channel quality after every TTI by sending the CQI3)CQI is sent after the very short period of time of 2 ms it is possible to effectively perform link adaptation even in rapidly changing conditions What is Latency in HSDPALatency is the time a packet needs to travel from sender to receiver While UMTS typically features an end-to-end latency of approximately 200ms HSDPA manages to lower the delay times in transmission to around 100ms What is Link AdaptionHSDPA uses link adaptation which means the way of transmission is changed according to the quality of the channel If a user is in favourable conditions for example close to the nearest antenna tower this user will be assigned a high data rateWhen the user moves into worse channel conditions for example far away from the antenna tower the transmission parameters will be changed accordingly and thus the data rate will be decreased

130) How power control is implemented in HSDPAAns- Initial power is set in the same way as open loop power control of DCH amp there is no further power control on HSDPA shared channel HS-DSCHThe channel rate is controlled by adaptive modulation amp coding formatThe principle amp functionality of the power control for the HSDPA associated dedicated channels are the same as for the DPCH power controlHS-DPCCH power is an offset relative to DPCCH depending upon whether the UE is in soft handoff or not The power of HS-SCCH is fixed125) What is Multiple PDP and what is meant by Multi RAB and multi call2 PS - Multiple PDPPS+CS ndash Multi RAB2CS ndash Multi Call110) What is Channelisation scramblingSpreading is applied to the Physical Channels (except SCH) It consists of two distinct operations a Channelisation and b Scrambling Channelisation is performed before scramblingChannelisationThe term spreading is also used to refer to channelisation Channelisation is the basis for Code Division Multiple Access (CDMA) encoding This operation transforms every data symbol of a signal into a number of chips The bandwidth of the resulting signal occupies a much larger bandwidth typically 5 MGHz and therefore the name Wideband-CDMA or W-CDMAThe number of chips per data

symbol is called the Spreading Factor (SF)Scrambling108) Features of Rel99Rel5Rel67 Release 99Release 99Bearer services64 kbits circuit switched384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Release 5 ndash 2002 High Speed Downlink Packet Access (HSDPA)

HSDPA Basic Concepts1)In HSDPA a common channel with fixed power is employed for data transfer Users are separated in both the time and code domains A fixed spreading factor is employed but multi codes operation is possible for increased data rates 2)Adaptive Modulation and Coding (AMC) replaces the role of power control so that the modulation and coding rate are changed depending on the channel condition 3)This is accomplished by locating the scheduling algorithm for channel allocation at the Node B instead of the RNC in Release 99

Drive Test and Radio-optimization for UMTSGSM Networks Introduction _ Site verification of radio parameters _ Network performance checking in static positions _ Network performance checking in mobile positions _ Area Drive test verification _ Drive test analysis amp recommendations _ Case Studies

Our company specialized in radio telecommunication puts under your disposition our skills and experiences concerning Site verification radio parameters - Drive test data - Analysis and recommendations in order to optimize the performance of our networkWe perform testing for 2G and 3G networks (GSMGPRSEDGE UMTSR99HSDPAHSUPA)

Preparation for DT (drive test) Hardware

Test phone Scanner GPS

Software Drive test software for example GENEX Probe Drive test post process software for example GENEX Assistant

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Combining (MDC) application handles the combining and splitting of the Media Access Control (MAC) frames arriving to the serving RNC from the IubIur interface during a soft handover The main functions offered by the MDC feature arebull Iu User Plane protocol towards the core network (CN)bull Radio Link Control (RLC) layer for RT databull ciphering of the RLCMAC PDUsbull Media Access Control (MAC) layer for dedicated channelsbull macrodiversity combining and splitting of the MAC framesbull Frame Protocol (FP) layer for Iub and Iur interfacesbull outer loop Power Control (PC) supportMacrodiversity Combining application is used in the Radio Network Controller (RNC)network elementWhat is RLC layer does Radio Link Control protocolThe RLC protocol implementation supports 3GPP Release 4 features transparent mode For transparent data transfer service the application supports segmentation and reassembly and transfer of user data functionsThe application also provides QoS setting and notification of unrecoverable errorsWhat is CipheringCiphering is always performed in the serving RNC Signalling procedures required for ciphering mode setting involve RANAP and RRC signalling for radio access bearer (RAB) parameter managementThe ciphering function is performed either in the RLC sub-layer or in the MAC sub-layeraccording to the following rulesbull If a radio bearer is using a non-transparent RLC mode (AM or UM) ciphering is performedin the RLC sub-layer Ciphering is performed on Payload Unit (PU) basisbull If a radio bearer is using the transparent RLC mode ciphering is performed in theMAC sub-layer (MAC-d entity)bull Only DTCH and DCCH channels are encryptedWhat is Power Control in RNCThe target of the power control (PC) is to achieve the minimum signal-to-interferenceratio (SIR target) that is required for the sufficient quality of the connectionWhat is Iu InterfaceThe Iu is the interface between the Core Network and WCDMA RAN moreprecisely between the RNC node and the different domains of Core Network The terms Iu-CS and Iu-PS are used to indicate associations to thecircuit switched network and the packet switched network respectively The term Iu-BC is used to indicate association to broadcast of unacknowledged messagesbull the Circuit Switched domain Iu-CS to MSC server (RANAP) and MGw (Iu User Plane)bull the Packet Switched domain Iu-PS to the SGSNbull the Broadcast domain Iu-BC from the Cell Broadcast Center (CBC) The Iu interface is an open standardized interface providing multi-vendorequipment to be supplied for both the Core Network and the WCDMA RAN

What is Iur InterfaceThe Iur interface is a WCDMA internal interface for the communication between two RNC nodes (and between two RNSs) It is an open and standardized interface The interface contains a control plane for radio signaling and AAL2 connection establishment and a user plane supporting guaranteed QoS on ATM or IP Notethat all ATM user plane traffic is carried on the same type of AAL2 connection packet data voice and Unrestricted Digital Information (UDI)159)What is HSUPAHSUPA stands for High Speed Uplink Packet Access and improves the uplink performance in networks which support HSUPA 3G networks support a maximum of 384kbps on the uplink HSUPA will support a maximum of 19Mbps The average uplink speed will be about 1Mbps160)Do 35GHSPA networks support VoiceHSPA is purely a data network All Voice traffic is supported on the current 3G network161)What are the benefits of using 35GHSPA for the end-userAs a result of the enhancement 35GHSPA promises a better broadband multimedia experience For the business user HSDPA enables high-speed Internet access and rapid download of emails with attachments For the consumers HSDPA allows faster downloading of high-resolution digital images high-quality music downloads Mobile TV and mobile multi-player games162)What do I need to enjoy the enhanced experience using 35GHSPA

To enjoy 35GHSPA services you will require a HSDPA-enabled phone and a 3G USIM163)What is the maximum download speed of StarHubs 35GHSPA networkStarHubs 35GHSPA network currently supports download speeds of up to 21Mbps and upload speeds of up to 576Mbps(Note Actual bandwidth and speeds experienced are dependent on a combination of factors including the mobile equipment software used internet traffic and destination server Presently only the Mobile Broadband Modem supports up to 21Mbps (download) and up to 576Mbps (upload) Most handsets available today only supports HSDPA with download speeds of up to 36Mbps and upload speeds of 384kbps)164)What affects the download and upload speeds when using the HSPA serviceAs with any network the actual bandwidth experienced will have to take into account network and protocol overheads and therefore the actual addressable bandwidth might be lower In addition to this performance will also be affected by the following the mobile equipment that you are using and the bandwidth it supports the websites and servers you are accessingthe types of Applications being used the radio conditions level of congestion on the InternetHSDPA in W-CDMAHigh Speed Downlink Packet Access (HSDPA) is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbps (and 20 Mbps for MIMO systems) over a 5MHz bandwidth in WCDMA downlink HSDPA implementations includes Adaptive Modulation and Coding (AMC) Multiple-Input Multiple-Output (MIMO) Hybrid Automatic Request (HARQ) fast cell search and advanced receiver designIn 3rd generation partnership project (3GPP) standards Release 4 specifications provide efficient IP support enabling provision of services through an all-IP core network and Release 5 specifications focus on HSDPA to provide data rates up to approximately 10 Mbps to support packet-based multimedia services MIMO systems are the work item in Release 6 specifications which will support even higher data transmission rates up to 20 Mbps HSDPA is evolved from and backward compatible with Release 99 WCDMA systems Currently (2002) 3GPP is undertaking a feasibility study on high-speed downlink packet access

What is benefit of shorter TTI in HSDPA1)After every TTI the resources can be redistributed among the users Therefore the resource usage is more efficient2)each UE reports about the channel quality after every TTI by sending the CQI3)CQI is sent after the very short period of time of 2 ms it is possible to effectively perform link adaptation even in rapidly changing conditions What is Latency in HSDPALatency is the time a packet needs to travel from sender to receiver While UMTS typically features an end-to-end latency of approximately 200ms HSDPA manages to lower the delay times in transmission to around 100ms What is Link AdaptionHSDPA uses link adaptation which means the way of transmission is changed according to the quality of the channel If a user is in favourable conditions for example close to the nearest antenna tower this user will be assigned a high data rateWhen the user moves into worse channel conditions for example far away from the antenna tower the transmission parameters will be changed accordingly and thus the data rate will be decreased

130) How power control is implemented in HSDPAAns- Initial power is set in the same way as open loop power control of DCH amp there is no further power control on HSDPA shared channel HS-DSCHThe channel rate is controlled by adaptive modulation amp coding formatThe principle amp functionality of the power control for the HSDPA associated dedicated channels are the same as for the DPCH power controlHS-DPCCH power is an offset relative to DPCCH depending upon whether the UE is in soft handoff or not The power of HS-SCCH is fixed125) What is Multiple PDP and what is meant by Multi RAB and multi call2 PS - Multiple PDPPS+CS ndash Multi RAB2CS ndash Multi Call110) What is Channelisation scramblingSpreading is applied to the Physical Channels (except SCH) It consists of two distinct operations a Channelisation and b Scrambling Channelisation is performed before scramblingChannelisationThe term spreading is also used to refer to channelisation Channelisation is the basis for Code Division Multiple Access (CDMA) encoding This operation transforms every data symbol of a signal into a number of chips The bandwidth of the resulting signal occupies a much larger bandwidth typically 5 MGHz and therefore the name Wideband-CDMA or W-CDMAThe number of chips per data

symbol is called the Spreading Factor (SF)Scrambling108) Features of Rel99Rel5Rel67 Release 99Release 99Bearer services64 kbits circuit switched384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Release 5 ndash 2002 High Speed Downlink Packet Access (HSDPA)

HSDPA Basic Concepts1)In HSDPA a common channel with fixed power is employed for data transfer Users are separated in both the time and code domains A fixed spreading factor is employed but multi codes operation is possible for increased data rates 2)Adaptive Modulation and Coding (AMC) replaces the role of power control so that the modulation and coding rate are changed depending on the channel condition 3)This is accomplished by locating the scheduling algorithm for channel allocation at the Node B instead of the RNC in Release 99

Drive Test and Radio-optimization for UMTSGSM Networks Introduction _ Site verification of radio parameters _ Network performance checking in static positions _ Network performance checking in mobile positions _ Area Drive test verification _ Drive test analysis amp recommendations _ Case Studies

Our company specialized in radio telecommunication puts under your disposition our skills and experiences concerning Site verification radio parameters - Drive test data - Analysis and recommendations in order to optimize the performance of our networkWe perform testing for 2G and 3G networks (GSMGPRSEDGE UMTSR99HSDPAHSUPA)

Preparation for DT (drive test) Hardware

Test phone Scanner GPS

Software Drive test software for example GENEX Probe Drive test post process software for example GENEX Assistant

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

To enjoy 35GHSPA services you will require a HSDPA-enabled phone and a 3G USIM163)What is the maximum download speed of StarHubs 35GHSPA networkStarHubs 35GHSPA network currently supports download speeds of up to 21Mbps and upload speeds of up to 576Mbps(Note Actual bandwidth and speeds experienced are dependent on a combination of factors including the mobile equipment software used internet traffic and destination server Presently only the Mobile Broadband Modem supports up to 21Mbps (download) and up to 576Mbps (upload) Most handsets available today only supports HSDPA with download speeds of up to 36Mbps and upload speeds of 384kbps)164)What affects the download and upload speeds when using the HSPA serviceAs with any network the actual bandwidth experienced will have to take into account network and protocol overheads and therefore the actual addressable bandwidth might be lower In addition to this performance will also be affected by the following the mobile equipment that you are using and the bandwidth it supports the websites and servers you are accessingthe types of Applications being used the radio conditions level of congestion on the InternetHSDPA in W-CDMAHigh Speed Downlink Packet Access (HSDPA) is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbps (and 20 Mbps for MIMO systems) over a 5MHz bandwidth in WCDMA downlink HSDPA implementations includes Adaptive Modulation and Coding (AMC) Multiple-Input Multiple-Output (MIMO) Hybrid Automatic Request (HARQ) fast cell search and advanced receiver designIn 3rd generation partnership project (3GPP) standards Release 4 specifications provide efficient IP support enabling provision of services through an all-IP core network and Release 5 specifications focus on HSDPA to provide data rates up to approximately 10 Mbps to support packet-based multimedia services MIMO systems are the work item in Release 6 specifications which will support even higher data transmission rates up to 20 Mbps HSDPA is evolved from and backward compatible with Release 99 WCDMA systems Currently (2002) 3GPP is undertaking a feasibility study on high-speed downlink packet access

What is benefit of shorter TTI in HSDPA1)After every TTI the resources can be redistributed among the users Therefore the resource usage is more efficient2)each UE reports about the channel quality after every TTI by sending the CQI3)CQI is sent after the very short period of time of 2 ms it is possible to effectively perform link adaptation even in rapidly changing conditions What is Latency in HSDPALatency is the time a packet needs to travel from sender to receiver While UMTS typically features an end-to-end latency of approximately 200ms HSDPA manages to lower the delay times in transmission to around 100ms What is Link AdaptionHSDPA uses link adaptation which means the way of transmission is changed according to the quality of the channel If a user is in favourable conditions for example close to the nearest antenna tower this user will be assigned a high data rateWhen the user moves into worse channel conditions for example far away from the antenna tower the transmission parameters will be changed accordingly and thus the data rate will be decreased

130) How power control is implemented in HSDPAAns- Initial power is set in the same way as open loop power control of DCH amp there is no further power control on HSDPA shared channel HS-DSCHThe channel rate is controlled by adaptive modulation amp coding formatThe principle amp functionality of the power control for the HSDPA associated dedicated channels are the same as for the DPCH power controlHS-DPCCH power is an offset relative to DPCCH depending upon whether the UE is in soft handoff or not The power of HS-SCCH is fixed125) What is Multiple PDP and what is meant by Multi RAB and multi call2 PS - Multiple PDPPS+CS ndash Multi RAB2CS ndash Multi Call110) What is Channelisation scramblingSpreading is applied to the Physical Channels (except SCH) It consists of two distinct operations a Channelisation and b Scrambling Channelisation is performed before scramblingChannelisationThe term spreading is also used to refer to channelisation Channelisation is the basis for Code Division Multiple Access (CDMA) encoding This operation transforms every data symbol of a signal into a number of chips The bandwidth of the resulting signal occupies a much larger bandwidth typically 5 MGHz and therefore the name Wideband-CDMA or W-CDMAThe number of chips per data

symbol is called the Spreading Factor (SF)Scrambling108) Features of Rel99Rel5Rel67 Release 99Release 99Bearer services64 kbits circuit switched384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Release 5 ndash 2002 High Speed Downlink Packet Access (HSDPA)

HSDPA Basic Concepts1)In HSDPA a common channel with fixed power is employed for data transfer Users are separated in both the time and code domains A fixed spreading factor is employed but multi codes operation is possible for increased data rates 2)Adaptive Modulation and Coding (AMC) replaces the role of power control so that the modulation and coding rate are changed depending on the channel condition 3)This is accomplished by locating the scheduling algorithm for channel allocation at the Node B instead of the RNC in Release 99

Drive Test and Radio-optimization for UMTSGSM Networks Introduction _ Site verification of radio parameters _ Network performance checking in static positions _ Network performance checking in mobile positions _ Area Drive test verification _ Drive test analysis amp recommendations _ Case Studies

Our company specialized in radio telecommunication puts under your disposition our skills and experiences concerning Site verification radio parameters - Drive test data - Analysis and recommendations in order to optimize the performance of our networkWe perform testing for 2G and 3G networks (GSMGPRSEDGE UMTSR99HSDPAHSUPA)

Preparation for DT (drive test) Hardware

Test phone Scanner GPS

Software Drive test software for example GENEX Probe Drive test post process software for example GENEX Assistant

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

symbol is called the Spreading Factor (SF)Scrambling108) Features of Rel99Rel5Rel67 Release 99Release 99Bearer services64 kbits circuit switched384 kbits packet switchedLocation servicesCall services compatible with Global System for Mobile Communications (GSM) based on Universal Subscriber Identity Module (USIM)Release 5 ndash 2002 High Speed Downlink Packet Access (HSDPA)

HSDPA Basic Concepts1)In HSDPA a common channel with fixed power is employed for data transfer Users are separated in both the time and code domains A fixed spreading factor is employed but multi codes operation is possible for increased data rates 2)Adaptive Modulation and Coding (AMC) replaces the role of power control so that the modulation and coding rate are changed depending on the channel condition 3)This is accomplished by locating the scheduling algorithm for channel allocation at the Node B instead of the RNC in Release 99

Drive Test and Radio-optimization for UMTSGSM Networks Introduction _ Site verification of radio parameters _ Network performance checking in static positions _ Network performance checking in mobile positions _ Area Drive test verification _ Drive test analysis amp recommendations _ Case Studies

Our company specialized in radio telecommunication puts under your disposition our skills and experiences concerning Site verification radio parameters - Drive test data - Analysis and recommendations in order to optimize the performance of our networkWe perform testing for 2G and 3G networks (GSMGPRSEDGE UMTSR99HSDPAHSUPA)

Preparation for DT (drive test) Hardware

Test phone Scanner GPS

Software Drive test software for example GENEX Probe Drive test post process software for example GENEX Assistant

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Hardware Checking_ For each cell we choose one location close the BTS The target Cell should be in the Light of Sight_ The following items should be checked approximately_ Antenna Azimuth_ Antenna TiltNote This test should be repeated for each SectorNetwork Checking_ For 2G Network Check we could collect the information below using an IDLE UE locked in 2G mode _ Frequency_ BCCH_ BSIC_ Cell ID_ LACRAC_ For 3G Network Check we may collect the information below using an IDLE UE locked in 3G mode _ Frequency_ Primary Scrambling Code_ Cell ID_ LACRACFor 2G Service Check we could do the following tests using a UE locked in 2G mode_ Mobile originated calls Mobile terminated calls EDGE FTP Download EDGE FTP Upload_ For 3G Service Check we are able to do the following tests using a UE locked in 3G mode_ AMR originated call AMR terminated call_ R99 FTP download R99 FTP Upload_ HSDPA FTP download and HSUPA FTP UploadFor 2G Service Check we use 2 UEs and one GPS in order to execute the long and short calls tests_ For 3G Service Check we use 2 UEs in order to execute the AMR long and short calls and data transferNote the test should be made Clockwise and anti clockwiseArea Drive test verificationAfter site verification of radio parameters itrsquos possible to perform Drive test in global area in order to optimize the radio performance (detect call drops Handover Failures Call set up Failures and resolve theseproblems)_ For 2G Service Check the following tests will be considered_ 2G Long and Short call_ Automatic Long call (2G and 3G)_ EDGE FTP Download_ MOS_ For 3G Service Check the following tests will be considered_ 3G short and Long call_ R99 FTP download_ HSDPA amp HSUPA FTP transfer_ MOS

RF OptimizationampDrive test WorkflowPreparation

Set the optimization target Divide the optimization cluster Draw out the test route line Prepare the DT tools The DT result is satisfiedwith optimization target

Problem Analysis neighbor cell list poor coverage pilot pollution handover Interference

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Engineering parameters adjust Neighbor cell list adjust

RF optimization KPI target-

RF optimization clusters divisionIn WCDMA we have divided to sites in Cluster is the area for one time drive test One cluster should contains

Drop Call Analysis - RF related issues Poor coverage (RSCP amp EcIo) High interference and hence poor EcIo Poor uplink coverage (insufficient UE Tx power) Poor dominance (best cell changes too frequently resulting in too many SHO events) Pilot pollution (too many cells present) Missing neighbors Fast change of RF conditions (eg turning a corner)

Check areas of poor coverage suggestion value as below Good RSCP ge -85 dBm Fair -95 dBm le RSCP lt -85 dBm Poor RSCP lt - 95 dBm

Examine the RSCP coverage on per cell bases in order to highlight any cells that have too large a footprint CPICH EcIo Plot

Good EcIo ge -8 dB Fair -14 dB le EcIo lt -8 dB Poor EcIo lt - 14 dB

WCDMA Evolution1)WCDMA evolved from GSMGPRS inheriting much of the upper layer functionality directly from those systems The first commercial deployments of WCDMA are based on a version of the standards called Release 992)Enhanced Data rates for GSM Evolution (EDGE) is another system in the GSMGPRS family that some operators have deployed as an intermediate step before deploying WCDMA

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

3)HSDPA was introduced in WCDMA Release 5 to offer higher speed Downlink data services4)Release 6 introduces the Enhanced Uplink (EUL) that will provide faster data services for the Uplink

Release 99 Packet Data1)There are different techniques defined in the Release 99 specification to enable Downlink packet data Most commonly data transmission is supported using either the Dedicated Channel (DCH) or the Forward Access Channel (FACH)2)The DCH is the primary means of supporting packet data services Each user is assigned a unique Orthogonal Variable Spreading Factor (OVSF) code dependent on the required data rate Fast closed loop Power Control is employed to ensure that a target Signal to Interference Ratio (SIR) is maintained in order to control the block error rate (BLER) Macro Diversity is supported using soft handover3)Data transfer can also be supported on the FACH This common channel employs a fixed OVSF code As it needs to be received by all UEs higher data rates are generally not supported Macro Diversity is also not supported and the channel operates with a fixed (or slow changing) power allocation Each data block contains a unique UE identifier that allows a given UE to keep itsown data and discard that belonging to other UEsThe Release 99 or current UMTS system provide data rates of 384Mbps to 2MbpsHSDPA will increase peak data rates up to 14Mbps

Release 99 Downlink Limitation Dedicated Channel Features ( DCH )

Maximum implemented downlink of 384kbps OVSF code limitation for high data rate users Rate switching according to burst throughput is slow Outer loop power control responds slowly to channel

Common Channel Features ( FACH ) Good for burst data application Only low data rates supported Fixed transmit power

Release 99 Downlink LimitationsAns-Although WCDMA Release 99 standard allows for maximum data rates of up to 20 Mbps it has only been widely implemented with a maximum data rate of 384 kbps This data rate is achieved by allocating a dedicated channel to each user The use of dedicated resources can be a limitation especially for data applications with bursty characteristics Each dedicated channel uses an OVSF code Shorter codes are used

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

for higher data rates and longer codes for lower data rates When an OVSF of a particular length is used all longer OVSF codes derived from that code become unavailable This limits the number of simultaneous high speed data users in a given cell The Release 99 standards provide support for a Secondary Scrambling Code which eases this limitation but it has not been widely implemented in commercial systems and will likely be removed from future versions of the specification The data rate of a dedicated channel can be adjusted to accommodate varying requirements of a data service application but the procedure for doing so is slow and thus inefficient Capacity is controlled both by the maximum amount of PA power that is available and by the power requirement of each data service In dedicated mode fast power control is used so that a target EbNo is achieved on the Downlink However the required EbNo set point changes at a much slower rate This can result in wasted resources whereby a better than required EbNo is achieved for the required BLERWCDMA Channels

Logical Channels Transport Channels PHYSICAL CHANNELS

Logical ChannelsThe MAC layer provides data transfer services on logical channels A set of logicalchannel types is defined for different kinds of data transfer services as offered by MACEach logical channel type is defined by the type of information that is transferredLogical channel types are depicted in Logical channels are classified intotwo groups

Control channels for the transfer of control plane information Traffic channels for the transfer of user plane information

Control channel (CCH)Control Channels Devide in to seven group

Broadcast control channel (BCCH) Paging control channel (PCCH) Dedicated control channel (DCCH) Common control channel (CCCH) Shared channel control channel (SHCCH) ODMA dedicated control channel (ODCCH) ODMA common control channel (OCCCH)

Broadcast control channel (BCCH) Downlink channel for broadcasting system control informationPaging control channel (PCCH) Downlink channel that transfers paging information and is used whenbull Network does not know the location cell of the mobile stationbull The mobile station is in the cell connected state (utilizing sleep mode procedures)Common control channel (CCCH) Bidirectional channel that transfers control information between network and mobile stations This channel is usedbull By the mobile stations having no RRC connection with the networkbull By the mobile stations using common transport channels when accessing a new cell after cell reselectionDedicated control channel (DCCH) Point-to-point bidirectional channel that transmits dedicated control information between a mobile station and the networkThis channel is established through RRC connection setup procedureODMA common control channel(OCCCH) Bidirectional channel for transmitting control information between Mobile stationsODMA dedicated control channel(ODCCH) Point-to-point bidirectional channel that transmits dedicated control information between mobile stations This channel is established through RRC connection setup procedureTraffic channel (TCH) are tow typs

Dedicated traffic channel (DTCH) ODMA dedicated traffic channel (ODTCH)

Dedicated traffic channel (DTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information A DTCH can exist in both uplink and downlinkODMA dedicated traffic channel (ODTCH) Point-to-point channel dedicated to one mobile station for the transfer of user information between mobile stations An ODTCH exists in relay link A point-to-multipoint unidirectional channel for transfer of dedicated user information for all or a group of specified mobile stationsTransport ChannelsThere exist two types of transport channels

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Dedicated channels Common channels

There is one dedicated transport channel the dedicated channel (DCH) which is a downlink or uplink transport channel The DCH is transmitted over the entire cell or over only a part of the cell using beam-forming antennas The DCH is characterized by the possibility of fast rate change (every 10 ms) fast power control and inherent addressing of mobile stationsshows the mapping between logical and transport channels The following connections existbull BCCH is connected to BCH and may also be connected to FACHbull PCCH is connected to PCHbull CCCH is connected to RACH and FACHbull SHCCH is connected to RACH and USCHFACH and DSCHbull DTCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH (FDD only)bull CTCH is connected to FACHbull DCCH can be connected to either RACH and FACH to RACH and DSCH to DCH and DSCH to a DCH a CPCH to FAUSCH CPCHPHYSICAL CHANNELSThe transport channels are channel coded and matched to the data rate offered by physical channels Thereafter the transport channels are mapped on the physical channels Physical channels consist of radio frames and time slots The length of a radio frame is 10 ms and one frame consists of 15 time slots A time slot is a unit which consists of fields containing bits The number of bits per time slot depends on thephysical channel Depending on the symbol rate of the physical channel the configuration of radio frames or time slots varies The basic physical resource is the codefrequency plane In addition on the uplink different information streams may be transmitted on the I and Q branch Consequently a physical channel corresponds to a specific carrier frequency code and on the uplink relative phase (0 or p2) There are two Physical Channes

Uplink Physical Channels Downlink Physical Channels

Uplink Physical Channels There are two uplink dedicated physical and two common physical channelsbull The uplink dedicated physical data channel (uplink DPDCH) and the uplink dedicated physical control channel (uplink DPCCH)bull The physical random access channel (PRACH) and physical common packet channel (PCPCH)Downlink Physical ChannelsThere is one downlink dedicated physical channel one shared and five common control channelsbull Downlink dedicated physical channel (DPCH)bull Physical downlink shared channel (DSCH)bull Primary and secondary common pilot channels (CPICH)bull Primary and secondary common control physical channels (CCPCH)bull Synchronization channel (SCH)Downlink dedicated physical channel (DPCH)The dedicated transport channel is transmitted time multiplexed with control information generated at layer 1 (known pilot bits power-control commands and an optional transport-format combination indicator) DPCH can contain several simultaneous services when TFCI is transmitted or a fixed rate service when TFCI is not transmitted The network determines if a TFCI should be transmittedCommon pilot channel (CPICH) Common pilot channel (CPICH) is a fixed-rate (30 Kbps SF=256) downlinkphysical channel that carries a predefined bitsymbol sequence There are two types of common pilot channels the primary and secondary CPICHPrimary and secondary common control physical channels (CCPCH)The primary CCPCH is a fixed-rate (30 Kbps SF=256) downlink physical channels used to carry the BCH Common control physical channels are not inner-loop power controlled Figure 611 shows the frame structure of the primary CCPCH The primary CCPCH is not transmitted during the first 256 chips of each slot Instead primary and secondary SCHs are transmitted during this periodsynchronization channel (SCH)the synchronization channel (SCH) used for cell search The SCH consists of two subchannels the primary and secondary SCH The primary SCH consists of a modulated code of length 256 chips the primary

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

synchronization code (PSC) transmitted once every slot The PSC is the same for every cell in the system

High Speed Downlink Packet Access (HSDPA) Release 5 - 2002

IP Multimedia Subsystem (IMS) IPv6 IP transport in UTRAN for Iub and Iur A UMTS packet air interface 36 Mbps up to theoretical 144 Mbps peakuser Use of 16QAM modulation in addition to QPSK modulation Add-on solution on top of 3GPP R99R4 architecture HSDPA terminals co-exist with R99 terminals No modification to the Core Network amp Traffic Classes

QPSK modulationQuadrature Phase Shift Keying (QPSK)HSDPA-Channels

New HSDPA Channels High Speed Downlink shared Channel ( HS-DSCH )

Downlink Transport Channel High Speed Shared Control Channel ( HS-SCCH )

Downlink Control Channel High Speed Physical Downlink Shared Channel ( HS-PDSCH )

Downlink Physical Channel High Speed Dedicated Physical Control Channel ( HS-DPCCH )

Uplink Control Channel

HS-PDSCH High-Speed Physical Downlink Shared Channelbull Transfer of actual HSDPA databull 5 - 15 code channelsbull QPSK or 16QAM modulationbull 2 ms TTIsbull Fixed SF16

Th HS DSCH channel is the data transport channel that all active HSDPA users connected to the NodeB will use The use of a shared channel is a key characteristic of HSDPA and being a common resource the HS-DSCH is dynamically shared between usersThe HS-DSCH supports adaptive coding and modulation changing to adapt to the changing conditions within the system The use of the 2ms TTI means that schedulingdelays are reduced and it also enables fast tracking of the channel conditionsallowing for the optimum use of the available resourceIt is worth noting that the HS-DSCH is not power controlled but rate controlledThis allowsthe remaining power after the other required channels have been serviced to be used for the HS-DSCH and this means that the overall power available is used efficiently

High Speed Signalling Control Channel (HS-SCCH)This HSDPA channel is used to signal the scheduling to the users every 2 ms according to the TTI The channel carries three main elements of information

It carries the UE identity to allow specific addressing of individual UEs on theshared control channel The HS-SCCH carries the Hybrid ARQ to enable the combining process to proceed This channel carries the Transport Format and Resource Indicator (TFRI) This identifies the scheduled

resource and its transmission formatHigh Speed Dedicated Physical Control Channel (HS-DPCCH)This HSDPA channel is used to provide feedback to the scheduler and it is located in the uplink The channel carries the following information

Channel Quality Information which is used to provide instantaneous channel information to the scheduler HARQ ACKNAK information which is used to provide information back about the successful receipt and

decoding of information and hence to request the resending information that has not been successfully receivedThese channels are added to the existing 3G UMTS channels and provide the additional data capability and adaptivity required to enable the much faster downloadspeeds provided by 3G HSDPA

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

HSDPA Sector Throughput The HSDPA sector throughput depends on many parameters such as Node B system loadingNode B scheduler algorithm UE capabilitiestraf c usage percentage of power allocatedto HSDPA radio environment (ie channel model)and the network layout Several simulations havebeen performed by QUALCOMM to estimatethe HSDPA sector throughput and its sensitivity to some of the above parameters It was found that for a typical outdoor urban environment(assuming 75 percent of the users are static or pedestrian and 25 percent are vehicular at30 kmh) the average sector throughput is 18to 22 Mbps for the basic con guration ( vecodes UE capability QPSK only and no receivediversity) This result is based on a Proportional Fair scheduler a full-buffer traf c model anda dedicated HSDPA frequency with 80 percent power for HSDPA users (ie 20 percent overheadchannels) This corresponds to an almost 200percent improvement over WCDMA Rrsquo99(700-800 kbps) and 350 percent over EGPRSAs shown in Figure 2-2 the sector throughput increases with the UE capabilities In fact15-code capability can improve the sector throughput by an average of 10 percent while16QAM modulation can add another six percentto eight percent Receive diversity if used canbring 40 to 55 percent improvement resulting ina sector throughput of 32 to 36 Mbps Note thatthe receive diversity gains derive from internal simulations assuming equal antenna gainsand no envelope correlation between the two antennas In reality the expected gains mightbe lower depending on the antenna gain difference (between the primary and thesecondary antenna) and the envelop ecorrelation coef cientThe use of equalization is also expected to further improve the sector throughput by an additional15 to 25 percentHSDPA Single Sites Problem1)Because In the Same RNC other Sites HSPA speed is normal so this is just single sites Problem this issue almost caused by IUB Transmittion2)What RF Person should firstly confirm is that the Parameter Setting is no Problem then we can ask BSS and Transmittion Person to check the IUB transmittion3)Checking the Sites(Cell) Parameter Configure in RNC according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before4)Checking NodeB Parameter Configure in NodeB according to the ldquoHSDPA DATA Transmittion Troubleshootingrdquo which I have give a training before(should log on NodeB)5)Do ldquoPing IPrdquo test in RNC to the Special NodeB6)Especially the size of the Packet should be 1500 the Number of Ping Packets should be at least 100If have any Packets lost it meas IUB transmittion have Problem

Maximum data rateFor example the largest transport block size is 27952 bits which corresponds to the highest data rate of 13976 Mbps (27952 bits2 ms = 13976 Mbps) This data rate isobtained by using 16QAM an effective code rate of 09714 and 15 HS-PDSCHsIn real life the 14 Mbps headline figure for HSDPA is not achievable It is physically possible to configure such a channel but there is nowhere it could be used The channel configuration requires close-to-perfect link conditions In Figure 13 the code domaindisplay that shows the 15 HS-PDSCHs with the 16QAM constellation display for one ofthe HS-PDSCHs illustrates that most of the cellrsquos capacity would be consumed by this high data rate HS-DSCH configurationRealistic peak data rates are likely to be much lower than 14 Mbps As an example themost stringent ldquosingle linkrdquo conformance test requirement for the UE in Release 5 isbased on a five-code QPSK channel with nominal data rate of 16 Mbps The required throughput is 1269 Mbps The most stringent ldquoclosed loop diversityrdquo conformance testrequirement for the UE in Release 5 is based on a four-code 16QAM channel with nominal data rate of 2332 Mbps The required throughput in this case is 15 Mbps Inboth these test cases the signal needs to be 10 dB above the noise and the UE consumeshalf the cell power

HSDPA Terminal Capability and Achievable Data RatesThe HSDPA feature is optional for terminals in Release 5 with a total of 12 different categories of terminal (from a physical layer point of view) with resulting maximum data rates ranging between 09 and 144 Mbps The HSDPA capability is other wise independent from Release rsquo99-based capabilities but if HS-DSCH has been configured for the terminalthen DCH capability in the downlink is limited to the value given by the terminal A terminal can indicate 32 64 128 or 384 kbps DCH capability as described in Chapter 6The terminal capability classes are shown in Table 113

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

The first ten HSDPA terminal capability categories need to support 16 QAM but the last two categories 11 and 12 support only QPSK modulation The differences between classes lie in the maximum number of parallel codes that must be supported and whether the reception in every 2 ms TTI is required The highest HSDPA class supports 10 Mbpsthere is the soft buffer capability with two principles used for determining the value for soft buffer capability The specifications indicate the absolute values which should be understood in the way that a higher value means support for incremental redundancy at maximum data rate while a lower value permits only soft combining at full rate While determining when incremental redundancy can be applied also one needs to observe the memory partitioning per ARQ process defined by the SRNC There is a maximum of eight ARQ processes per terminal

Category number 10 is intended to allow the theoretical maximum data rate of 144 Mbpspermitting basically the data rate that is achievable with rate 13 turbo coding and significant puncturing resulting in the code rate close to 1 For category 9 the maximum turboencoding block size (from Release rsquo99) has been taken into account when calculating the values thus resulting in the 102 Mbps peak user data rate value with four turbo-encoding blocks It should be noted that for HSDPA operation the terminal will not report individual values but only the category 12 distinct terminal classes From a Layer 23 point of view the important terminal capability parameter to note is the RLC reordering buffer size that basically determines the window length of the packets that can be lsquoin the pipelinersquo to ensure in-sequence delivery of data to higher layers in the terminal The minimum values range from 50 to 150 kB depending on the UE categoryBesides the parameter part of the UE capability the terminal data rate can be largely varied by changing the coding rate as well Table 114 shows the achievable data rates when keeping the number of codes constant (15) and changing the coding rate as well as the modulation Table 114 shows some example bit rates without overhead considerations for different transport format and resource combinations (TFRCs)

These theoretical data rates can be allocated for a single user or divided between several users This way the network can match the allocated powercode resources to the terminal capabilities and data requirements of the active terminals In contrast to Release rsquo99 operation it is worth noting that the data rate negotiated with the core network is typically smaller than the peak data rate used in the air interface Thus even if the maximum data ratenegotiated with the core network was eg 1 Mbps or 2 Mbps the physical layer would use (if conditions permit) a peak data rate of eg 36 Mbps

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

HSDPA-Throughput Analysis

a)HSDPA Radio ChartsThe information presented in the five charts within this form is the most useful for determiningthe cause of low throughputi)CQI ndash UE reported CQIii)Throughput (RAW and MAC) ndash plot of raw physical layer throughput with MAC layerthroughputiii)ACKNACK ndash percentage of Acknowledgments and Negative Acknowledgements sentincluding DTX samples in the total sample spaceiv)DTX ndash discontinuous transmission DTX rate is equal to the total Number of DTX receiveddivided by the total number ACK NACK and DTX reported as a percentagev)MAC FER ndash MAC frame erasure rate is the number of HS-DSCH blocks received in errorover the total number of valid HS-SCCH decodesb)HSDPA Radio TableThe information presented in this table provides an instantaneous reference fora)CQI ndash UE reported CQIb)Max CQI expected ndash maximum CQI achievable based on UE classcC)NACK Rate (without DTX) ndash NACK when considering only received transport blocksd)HS-MAC BLER ndash block error rate as seen at the MAC-hs entity in the UEe)16 QAM Modulation usage ndash percentage of TTIrsquos over a 200ms interval that use 16QAMf)UE State ndash indication of the current UE state useful to check if UE is in HS-DSCH state atthe time of a low throughput eventg)Time ndash timestamp of the selected event or point in the fileh)HS Serving Celli i)SC ndash scrambling code of the active set cell transmitting the HS-PDSCHii ii)EcNo ndash current EcNo of the serving scrambling code

2 No HS-DSCH Assignment HS-PDSCH Assignment ndash if the HS-PSDSCH is not available the UE will be assigned (resourcedependent) a R99 DCH bearer This will result in lower than expected throughput as R99 DCHbearers have a maximum bearer rate of 384kbps A HS-PDSCH is assigned to UE provided aHSDPA is configured and is operational in the cell bUE supports HSDPA cThe number of users allocated in a cell does not exceed 16 dSufficient code resources are available eDownlink Load is below the admission threshold for HSDPA fUplink Load is below the admission threshold for the creation of the associated DCHRecommendation confirm parameter set is aligned to CIQ and HSDPA is enabled in the cellCheck for abnormally high load (UL and DL) using RNC counters over a low traffic period Faultrelated loading may result in the allocation of a non-HSDPA bearer if high load is present withlow traffic this indicates a problem with the Node B or antenna system escalate to fieldoperations to investigate further

3 Low CQICQI ndash Channel Quality Indicator ndash is a measure of channel quality estimated and reported bythe UE and possibly adjusted by the NodeB before being used with lookup tables to determinethe appropriate TFRC to use in the next scheduled TTI As the NodeB does may not directly usethe reported CQI values discrepancy between the allocated TFRC and expected TFRC ispossible however commonly low CQI results in a TFRC with low user data throughput and ahigh CQI results in high throughput within the capability of the UE and network example of how CQI affects throughput In this example CQI increases fromapproximately 15 to 21 as a result of a HS-DSCH switch resulting in a significant increase inthroughputRecommendation low CQI indicates poor channel quality resulting from low RSCP and orEcNo Optimize the downlink coverage in the area of concern to improve coverage and ordominance The same steps as presented for the coverage analysis in the R99 DCH may befollowed

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

4 High DTX DTX ndash The DTX percentage is a measure of the percentage of available TTIrsquos a given UE has Not been scheduled for that is a high value near to 100 indicates that the UE is rarely beingscheduled a value close to 0 indicates that the UE is nearly always being scheduled Thefollowing are possible causes of high DTXA)UE is incapable of receiving subsequent TTIrsquos as defined by UE classb)UE is being starved (under-scheduled) by an unfair scheduler (eg MAX CQI orProportional Fair with low fairness)c)Lack of data to transmit ie The Node Brsquos buffer for the given UE is empty at or for anumber scheduling intervals iCongestion on the Iub preventing the NodeB buffer from being replenished iiSlow or congested application serverD)UE does not receive scheduling indications on the HS-SCCH due to poor downlink coverageinterferencee)Level of sharing on the HS-PDSCH ndash ie Number of users If there are two activeHSDPA users in a cells coverage area DTX will approximate 50 per user (assuminground robin scheduling) and throughput will be halved

Recommendation Where a consistently high DTX rate is observed in good RF across a widearea of a cells footprint it is probable that there is a hardware issue at the NodeB this should beescalated to field operations to investigate further on site It may be necessary to re-commissionHSDPA on the siteWhere high DTX is observed sporadically throughout a session it is probable that there isinsufficient data in the buffers for the UE to be continuously scheduled this can be due tocongestion in the Iub or an under-performing FTP server Verify the performance of the FTPserver with static testing and check RNC counters for Iub congestion events5 High NACK ACK vs NACK ndash For every TTI in which a UE is scheduled to receive data the UE will respondby sending an ACK or NACK depending on whether or not the transmission was correctlyreceived or not (Note that if the UE does not receive the scheduling information on the HS-SCCH no HARQ response is sent (DTX))As each NACK requires a physical layer retransmission of the transport block a high percentageof NACKrsquos can cause low throughput This is only true where Uu_ HSDPA_Throughput_MACdecreases as a result It is feasible that the retransmissions can be absorbed with a higherUu_HSDPA_Payload_L1 rateA consistently high NACK indicates that the link adaptation algorithm is not able to adequatelytrack the radio environment this can result froma)NodeB or ATS problem ndash when a site or cell is consistently showing high NACK for allsessions on the site cell this can indicate a problem with the NodeB configuration orantenna systemb)UE is over reporting CQI ndash less likely scenario as CQI reporting accuracy is standardizedThere is still a possibility that a UE under performs in this area however and this willcause a reduction in system throughput when more than one user is active in a cellRecommendation If present consistently from a given time to the end of the drive test verifythe UE performance in a static test to rule this out as a cause If the problem is observed on allHSDPA connections in a particular cell escalate to a field technician to verify the antenna systemand antenna system settings in the NodeB for the affected cellcells and to confirm the HSDPA commissioning parameters these should align to the CIQ data To overcome UE CQI over-reporting it is possible to use the E RBS cqiAdjustmentOn parameter This activates the NodeBCQI adjustment algorithm which targets a NACK of 10 Warning ndash this can result is reduceduser throughput in good RF This parameter should not be changed without prior approval6 MobilityMobility ndash while mobility should no longer severely impact user throughput (with the use of A-DCH SHO and HS-PDSCH switching) it is possible that incorrectly set mobility parameters forHSDPA may cause delayed HS-PDSCH switching as a result the HS-PDSCH may not always beon the best server and experience lower than achievable throughput In addition constantswitching or ping pong switching can cause reduced application throughput as data in the sourceNodeB buffer is discarded and recovered in the target cell through higher layer retransmissions(RLC)Recommendation verify e1d trigger parameter alignment optimize SHO area by creatingsingle cell dominance in the affected area

HSUPA(High Speed Uplink Packet Access)This introduces an important feature of 3GPP R6 High Speed Uplink Packet Access (HSUPA) As an uplink (UL) high speed data transmission solution HSUPA provides a theoretical maximum UL rate of 576 Mbps on the Uu interface The peak data rate supported by Huawei RAN61 is 192 Mbps It improves user experience with significantly higher

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

data rate lower delay and faster connection setup which allows operators to offer new services and attract new usersHigh Speed Uplink Packet Access (HSUPA)

1 In HSUPA the Node B allows several UEs to transmit at a certain power level at the same time These grants are assigned to users by using a fast scheduling algorithm that allocates the resources on a short-term basis (every 10ms or 2ms)

2 The rapid scheduling of HSUPA is well suited to the bursty feature of packet service During periods of high activity a given user may get a larger percentage of the available resources while getting little or no bandwidth during periods of low activity

New Uplink Transport Channel

Adaptive Modulation and Coding ( AMC ) AMC ( Adaptive Modulation and Coding ) based on CQI ( Channel Quality Indicator ) UE measures the channel quality and reports to NodeB every 2ms or more cycle NodeB selects modulation scheme data block size based on CQI

CQI Mapping Table

W-CDMA Wideband Code Division Multiple Access (W-CDMA) brings GSM into 3G W-CDMA is a type of 3G cellular network and is a highspeed transmission protocol used in Universal Mobile Telecommunications System (UMTS) UMTS offers packet-based transmission for text digitized voice video and multimedia contentHSPAHigh-Speed Packet Access (HSPA) is a mobile telephony protocol that helps improve the performance of UMTS HSPA uses improved modulation schemes while refining the protocols that mobile devices and base stations use to communicate These processes improve radio bandwidth utilization provided by UMTSHSDPAHigh-Speed Downlink Packet Access (HSDPA) is a 3G mobile telecommunications protocol from the HSPA mobile protocol family HSDPA enables higher data transfer speeds and capacity in UMTS-based networks The standard currently supports peak downlink speeds of up to 144 Mbps in 5 MHz bandwidthHSUPAHigh-Speed Uplink Packet Access (HSUPA) is also a 3G mobile telecommunications protocol from the HSPA mobile protocol family The HSUPA protocol enables peak uplink speeds of up to 576 Mbps

HSPA+Evolved HSPA (HSPA+) is a wireless broadband standard that provides peak speeds of up to 42 Mbps on the downlink and 22 Mbps on the uplink using multiple-input multiple-output (MIMO) technology and higher order modulation

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

WCDMA MOC Call Flow

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

R99 Call Flow

HSDPA Call Flow

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Lte- UTRAN Long Term Evolution (LTE) The 3GPP Long Term Evolution (LTE) represents a major advance in cellular technology LTE is designed to meetcarrier needs for high-speed data and media transport as well as high-capacity voice support well into the next decadeIt encompasses high-speed data multimedia unicast and multimedia broadcast services Although technicalspecifications are not yet finalized significant details are emerging This paper focuses on the LTE physical layer(PHY)The LTE PHY is a highly efficient means of conveying both data and control information between an enhanced basestation (eNodeB) and mobile user equipment (UE) The LTE PHY employs some advanced technologies that are newto cellular applications These include Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) data transmission In addition the LTE PHY uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink (DL) and Single Carrier ndash Frequency Division Multiple Access (SC-FDMA) on the uplink (UL)OFDMA allows data to be directed to or from multiple users on a subcarrier-by-subcarrier basis for a specified numberof symbol periods Due to the novelty of these technologies in cellular applications they are described separately before delving into a description of the LTE PHYAlthough the LTE specs describe both Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD) toseparate UL and DL traffic market preferences dictate that the majority of deployed systems will be FDD This papertherefore describes LTE FDD systems onlyLTE Release 8 Key Features

High spectral efficiency OFDM in Downlink Single Carrier‐ FDMA in Uplink

Very low latency Short setup time amp Short transfer delay Short hand over latency and interruption time

Support of variable bandwidth 14 3 5 10 15 and 20 MHz

Compatibility and interworking with earlier 3GPP Releases FDD and TDD within a single radio access technology Efficient MulticastBroadcast

LTE Design GoalsThe LTE PHY is designed to meet the following goals [1]1 Support scalable bandwidths of 125 25 50 100 and 200 MHz2 Peak data rate that scales with system bandwidth a Downlink (2 Ch MIMO) peak rate of 100 Mbps in 20 MHz channel b Uplink (single Ch Tx) peak rate of 50 Mbps in 20 MHz channel3 Supported antenna configurations a Downlink 4x2 2x2 1x2 1x1 b Uplink 1x2 1x14 Spectrum efficiency a Downlink 3 to 4 x HSDPA Rel 6 b Uplink 2 to 3 x HSUPA Rel 6

5 Latency a C-plane lt50 ndash 100 msec to establish U-plane b U-plane lt10 msec from UE to server6 Mobility A Optimized for low speeds (lt15 kmhr) B High performance at speeds up to 120 kmhr C Maintain link at speeds up to 350 kmhr7 Coverage a Full performance up to 5 km b Slight degradation 5 km ndash 30 km c Operation up to 100 km should not be precluded by standard

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

23 Supported F requency bands The LTE specifications inherit all the frequency bands defined for UMTS whichis a list that continues to grow There are at the time of this writing 15 FDDoperating bands and 8 TDD operating bands Significant overlap exists betweensome of the bands but this does not necessarily simplify designs since therecan be band-specific performance requirements based on regional needs Thereis no consensus on which band LTE will first be deployed since the answeris highly dependent on local variables This lack of consensus is a significantcomplication for equipment manufacturers and contrasts with the start of GSMand W-CDMA both of which were specified for only one band What is nowfirmly established is that one may no longer assume that any particular band isreserved for any one access technologyEvolved UMTS Radio Access Network (EUTRANbull Downlink OFDM 100Mbps+ (20MHz spectrum) bull Uplink SC-FDMA 50Mbps+ (20MHz spectrum) bull (Orthogonal Frequency Division Multiplexing (OFDM) ndash based radio design and techniques are used to spread data over many sub-carriers provides greater immunity to fading resulting in an overall increase in delivery reliability) bull FDD ndash Frequency Division Multiplexbull End-user latency lt10mS bull Control plane latency (Transition time to active state) lt 100mS (for idle to active)bull Flexible and Scaleable Bandwidth ndash (125 25 5 10 15 and 20MHz) 125MHz suitable for in- band migration (re-use of existing spectrum) and 5MHz ndash 20MHz for clear spectrum green field deployments and expansion of spectrum as demand growsbull Frequency spectrum choice and flexibility of deployment in GSM CDMA UMTS bands (450 700 850 900 1700 1800 1900 2100 2500MHz) means that global roaming will be possiblebull Mobility will be supported up to 500kmph but like other technologies will be optimized for lower speeds (from 0 to 15kmph)bull Coverage (Cell sizes) 5 ndash 100km with slight degradation after 30kmbull VoIP Roughly 3 times UMTS voice capacitybull MIMO - Advanced antennas already standardized will increase the overall sector throughputbull E2E QOS allowing prioritization of different class of service

Advantages of 4G Wireless Systems

Support for interactive multimedia voice streaming video Internet and other broadband services IP based mobile system High speed high capacity and low cost per bit Global access service portability and scalable mobile services Seamless switching and a variety of Quality of Service driven services Better scheduling and call admission control techniques Ad hoc and multi hop networks (the strict delay requirements of voice make multi hop network service a difficult problem)Better spectral efficiency Seamless network of multiple protocols and air interfaces (since 4G will be all ]IP look for 4G systems to be compatible with all common network technologies including80211 WCDMA Blue tooth and Hyper LAN) An infrastructure to handle pre existing 3G systems along with other wireless technologies some of which are currently under developmentPCI Planning There are two main strategy options_ Neighboring sites are grouped into clusters and each cluster is assigned a limited number of Code Groups Each site is assigned a specific Code Group and each sector a specificColor Group_ Random planning ie PCI plan that does not consider PCI grouping and does not follow any specific reuse pattern

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

PCIs should be split into 3 different color groups and 168 code groups_ Code groups should be reserved for special purposes eg inbuilding and PLMN borders or for future expansions_ If a color group is assigned per sector and a code group is assigned per site this will eliminate the risk of having the same k or frequency shift in the same site in adjacent cells or pointing at each other

Typically 10-15 3-sector sites in a clusterUse a subset of the code groups in each clusterIf there are ~70 code groups available PCIs may be repeated everyfifth or sixth clusterStructured planning like this eliminates the risk of havingconflicting k or frequency shift in the same site in adjacent cells orpointing at each otherAlso the risk of having conflicting SSS sequences in adjacent cellsis reduced ndash although this may appear at cluster borders

LTE Supporting Technologies-MIMOMIMO (multiple input multiple output) is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver) The antennas at each end of the communications circuit are combined to minimize errors and optimize data speed MIMO is one of several forms of smart antenna technology the others being MISO (multiple input single output) and SIMO(single input multiple output)In conventional wireless communications a single antenna is used at the source and another single antenna is used at the destination In some cases this gives rise to problems with multipath effects When an electromagnetic field (EM field) is met with obstructions such as hills canyons buildings and utility wires

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

the wavefronts are scattered and thus they take many paths to reach the destination The late arrival of scattered portions of the signal causes problems such as fading cut-out (cliff effect) and intermittent reception (picket fencing) In digital communications systems such as wireless Internet it can cause a reduction in data speed and an increase in the number of errors The use of two or more antennas along with the transmission of multiple signals (one for each antenna) at the source and the destination eliminates the trouble caused by multipath wave propagation and can even take advantage of this effectBenefit of MIMOThe benefits of different MIMO schemes in downlink are roughly as follows1)transmit power is doubled by adding another amplifier (3dB)ii)average received signal power is doubled because of two-antenna reception (3dB)iii) diversity from four signal paths brings additional gain which however strongly depends on thepropagation environment (here pessimistically assumed 0 minus1dB higher gains are possible)

OFDM (Orthogonal Frequency Division Multiplex)OFDM technology has been incorporated into LTE because it enables high data bandwidths to betransmitted efficiently while still providing a high degree of resilience toreflections and interference The access schemes differ between the uplink anddownlink OFDMA (Orthogonal Frequency Division Multiple Access is used inthe downlink while SC-FDMA(Single Carrier - Frequency Division MultipleAccess) is used in the uplink SC-FDMA is used in view of the fact that its peak to average power ratio is small and the more constant power enables high RF power amplifier efficiency in the mobile handsets - an important factor for battery power equipmentSAE ( System Architecture Evolution) With the very high data rate and lowlatency requirements for 3G LTE it is necessary to evolve the systemarchitecture to enable the improved performance to be achieved One change isthat a number of the functions previously handled by the core network have beentransferred out to the periphery Essentially this provides a much flatter formof network architecture In this way latency times can be reduced and data can be routed more directly to its destination3G LTE specification overviewIt is worth summarizing the key parameters of the 3G LTE specification In view of thefact that there are a number of differences between the operation of the uplink anddownlink these naturally differ in the performance they can offer Parameter Details

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

These highlight specifications give an overall view of the performance that LTE willoffer It meets the requirements of industry for high data download speeds as well asreduced latency - a factor important for many applications from VoIP to gaming and interactive use of data It also provides significantimprovements in the use of theavailable spectrum

Lte-ChannelsTransport channels In order to reduce complexity of the LTE protocol architecture the number of transport channels has been reduced This is mainly due to the focus on shared channel operation ie no dedicated channels are used any moreDownlink transport channels are

Broadcast Channel (BCH) Downlink annShared Chel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH)

Uplink transport channels are Uplink Shared Channel (UL-SCH) Random Access Channel (RACH)

Logical channels Logical channels can be classified in control and traffic channels

Control channels are Broadcast Control Channel (BCCH) Paging Control Channel (PCCH) Common Control Channel (CCCH) Multicast Control Channel (MCCH) Dedicated Control Channel (DCCH)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

Traffic channels are Dedicated Traffic Channel (DTCH) Multicast Traffic Channel (MTCH

eNB FunctionalitiesFunctions for Radio Resource Management Radio Bearer Control Radio Admission Control Connection Mobility Control Dynamic allocation of resources to UEs in both uplink and downlink (scheduling) IP header compression and encryption of user data stream Selection of an MME at UE attachment when no routing to an MME can be determined from the information provided by the UE Routing of User Plane data towards Serving Gateway Scheduling and transmission of paging messages (originated from the MME)Scheduling and transmission of broadcast information (originated from the MME or OampM)Measurement and measurement reporting configuration for mobility and schedulingScheduling and transmission of PWS (which includes ETWS and CMAS) messages (originated from the MME)

LTE (RF)Drive Test-optimization

To meet customers requirements for high-quality networks LTE trialnetworks must be optimized during and after project implementation Radiofrequency (RF) optimization is necessary in the entire optimization processThis document provides guidelines on network optimization for networkplanning and optimization personnel

Single site verification Single site verification the first phase of network optimization involvesfunction verification at each new site Single site verification aims toensure that each site is properly installed and that parameters arecorrectly configured1)First should check the azimuth and tilt any problem the work should bestopped and directly inform Huawei the problems2)The DT teams should select points as below (updated 147 are canceledonly 6 points needed) to do the network entry Download upload ping testThe points location can be changed as the real signal condition3)If the teams find any problem (include but not only wrong BSID or PCI lowthroughput high ping delay) in the test they should report it to coordinator right now Take care on the feeder across At last finish and submit the SSVreport (refer to the attachment)

4)If there is no cross feeder the terminal should access to correct BSIandcorrect PCI If there is cross feeder please report to Huawei SSV supervisor And the remaining test for this site should be stopped5)Throughput test should be done with FTP Currently there is one Huawei FTP is available for throughput test FTP IPftp10218240115user name huawei password huaweiftp10212195139 user name wimaxpassword wimax Please use FTP software (suggest to use filezillabecause it can download several files together) to download the files (atleast 10 files together) at least for 1 minute Using first stopwatch of DUmeter to record the average DLUL throughput during test6)All the throughput test mentioned in this document must beperformed in this way7)Ping test click ldquostartrdquo button on your desktop and then Start-gt Run-gt inputrdquocmdrdquo-gt enter-gt input rdquoping 10218240115 ndashn 100rdquo or rdquoping10212195139 ndashn 100rdquo gt enter-gt wait until output 10 ping delay result onthe screen-gt record the average ping delay8)Take a snapshot which includes all the above test result (ping anddownload upload) signal information PCI terminal Tx power etc

Define services to be testedVoice Video FTP HTTP FTP Ping etcMode of service HSPA HSDPA LTEThese tables and passfail criteria must be established

3)Begin DTiThe DT will follow before confirmed wimax DT boundary Using HuaweiE398s USB terminal and Huawei Genex Probe DT software to perform theDT During the DT the engineers should parallel perform network entryminimum guarantee DownLoadUpLoad test By this after the DT can getthe test result of coverage probability successful setup rate sessionestablish delay dropped session rate minimum rate guarantee of downstreamampupstream handoff wireless link burst error rateiiAll the streets should be covered The speed should less than 30kmh Inthe DT engineers should always pay attention on the PCIRSRPSINR If any problem happened they should click the ldquopauserdquo button to pause thetest and after solving continue the test Any problems like KPI fail toachieve must be informed to Huawei on time After DT the log should betransferred to Huaweiiii)In the DT the team should always take care the PCI and performance thebad performance DT log or wrong test log will need repeating work It is ok that feedback the problems to Huawei when you mee some problems4)Begin PT(point test)iCell edge coverage probabilityTo the cell edge coverage probability select 20 edge points (SINR is higher than0dBbut lower than5dBamp RSRP is lower than-100dB) to perform ftpdownload each point last 1 min Record the detail coordinates and test resultshe RSRP and SINR must be check from Probe you can use test plan todownload and take a Snapshots like the ldquoAverage downstream throughput ndashsector levelrdquo pictures check the RSRP and SINR like this picture

Acceptable range successful rategt 80Target range successful rategt 85ii Av er ag e d ow ns tre am th ro ughp ut ndash ter minal leve l

To the average downstreamupstream throughput (terminal level) select 3points of one sector (RSRP=-105~-95 -95~-80 gt-80SINR=0~1015~2525~35) to perform the ftp download upload for 1 minRecord the average throughput of the 3 points This test should be implementedfor 20 of sectors per clusterPlease pay more attention to 3 pointsRSRP=-105~-95SINR=0~10 keep the DL throughput between 5M to 15MRSRP=-95~-80 SINR=15~25 keep the DL throughput between 25M to 35MRSRPgt-80 SINR=25~35 keep the DL throughput between 45M to 55M

The RSRP must be check from Probe then you can test plan to finish thisworkThis test plan PT will be provided by huawei And you need to take aSnapshots like the ldquoAverage downstream throughput ndash sector levelrdquo pictures3Measure MethodKPI Test includes DT and PT (point test)1 )DT(Drive Test) i)The DT will follow before confirmed wimax DT boundary Using HuaweiE398s USB terminal and Huawei Genex ProbeampAssistant DT softwareto perform the DT During the DT the engineers should parallelperform network entry minimum guarantee DownLoadUpLoad testBy this after the DT can get the test result of coverage probabilitysuccessful setup rate session establish delay dropped session rateminimum rate guarantee of downstreamampupstream handoff HSRwireless link burst error rateii)To the coverage probability need to show out the statistic of pointspercentage of RSRPgt-110dBmampSINRgt-3dB show the RSRP amp SINR ampPCI map pictureiii)Successful setup rate= ERAB Setup Success Counter ( ERAB SetupSuccess Counter + ERAB Setup Failure Counter)iv)Session establishment delay= T(Attach CMP)-T(Attach REQ)v)Dropped session rate= ERAB Abnormal Rel Counter ERAB Setup SucCountervi)To the minimum rate guarantee of downstreamampupstream theengineers will perform ftp download and upload by one fixed size file(DL 80MB and UL 20MB) withnon-GBR account thedownloadampupload will be ceaselessly repeated until finish the DT Then calculate the average throughput of these tests The test resultwill be filtered as contract requirements and only the valid serviceresult will be calculated This after filter result will be the KPI result of this test itemvii)Handover successful rate(HSR)= HO Success Counter ( HO SuccessCounter + HO Failure Counter)viii)In any 1 min of the DT cannot happen more than 6 times HO if thisnot happen the handoff test is passedix)To the wireless link burst error rate calculate the average RBLER inthe DT the average RBLER of the DT should be less than 1 toachieve the contract KPIx)All the above test result will be filtered as the RF test conditiondefined in contract and the final result listed in the report shouldbase on the test result after this filter The service drop or test failhappened at bad RF points defined by contract will be excludedBesides Huawei should provide all the original logs when submit theKPI reports2 )PT(Point Test) xi)To the cell edge coverage probability select 20 edge points (SINR ishigher than 0dB but lower than 5dB amp RSRP is lower than -95dBm) toperform ftp download each point last 1 min Do a statistic for thesuccessful service points percentagexii)To the average downstreamupstream throughput (terminal level)select 3 points (RSRP=-105~-95 -95~-80 gt-80) to perform the ftpdownload upload for 1 min Record the average throughput of the 3points This test should be implemented for 20 of sectors perclusterxiii)To the average downstreamupstream throughput (sector level) use 2or 3 terminals (can be negotiated by Mobily amp Huawei to detail testrequiremtns) to perform the ftp download upload for 1 min at thesame time In the 2 terminals condition the modulation should bearound 64QAM and 16QAM This test should be implemented for 20of sectors per clusterxiv)To the Maximum round trip latency select 1 edge point (RSRP=-100~-90) to perform the ping test The ping packet size is 32KB and theping repeat times is 100 Record the average ping delay This testshould be implemented for 20 of sectors per clusterxv)Calculate the maximum jitter based on above ping result 5 biggest jitter values should be canceled This test should be implemented for20 of sectors per cluster

xvi)As contract requirements if the site has other commercial users thethroughput KPI is not must achieved DT team just normally recordthe test result amp the slot occupy rate from NOC M2000 For that thetest is a long term work and the ftp problem is always met as toavoid any delay by the ftp server to all the ftp related test itemsHuawei can use either Mobily ftp server (ftpbayanatcomsa) orHuawei serverxviiHuawei should provide all the original logs when submit the KPIreportsCluster Pre-DriveSystem Check

Get latest cluster drive routes 90 cluster readiness ( You can set whatever readiness your methodology allows for )No major alarms ( From OSS -So you can make sure that OSS team must send a copy of the BTS or eNB alarm reports at the beginning of each day if possible )Ensure the sites in the test clusters are unlocked and put on ldquocell - reservedrdquo Activate the UETR tracing in OSS (if available)

(Letrsquos add one more term make sure to activate UETR for the correct number Check List during Drive

Check that logfiles are active and recording while driving If DLUL sessions stop or hang unexpectedly during testing stop and re-start session Note problematic areas such as those below -

Poor RSCP (lt-100dBm) Poor CINR (lt0dB) Low DL throughput (lt5Mbps) Sites not transmitting even when UE is at close range Swapped feeders (PCI not present at expected coverage area) Laptop UE connection problems etc Take note of inaccessible drive routes Drive round the site in both clockwise and anti-clockwise direction (Onlyapplicable for

single site test)

RSRP of LTE cells(Reference Signal Received Power) RSRP is a RSSI type of measurement It measures the average received power over the resource elements that carry cell-specific reference signals within certain frequency bandwidth RSRP is applicable in both RRC_idle and RRC_connected modes while RSRQ is only applicable in RRC_connected mode In the procedure of cell selection and cell reselection in idle mode RSRP is used RSRP is the LTE equivalent of 3G UMTS RSCPRSRQ of LTE cells ( Re f erence Signal Received Quality) RSRQ is a CI type of measurement and it indicates the quality of the received reference signal It is defined as (NRSRP)(E-UTRA Carrier RSSI) where N makes sure the nominator and denominator are measured over the same frequency bandwidth RSRQ is the LTE equivalent of 3G UMTS Ec N0bullUTRA RSSI The carrier RSSI (Receive Strength Signal Indicator) measures the average total received power observed only in OFDM symbols containing reference symbols for antenna port 0 (ie OFDM symbol 0 amp 4 in a slot) in the measurement bandwidth over N resource blocks The total received power of the carrier RSSI includes the power from co-channel serving amp non-serving cells adjacent channel interference thermal noise etcbullGSM Carrier RSSI This is the RSSI (in dBm) for the signal level of the GSM cells measuredon the UErsquos receiver antenna and compared to a reference level of 1mW

RSRP RSRQ RSSI are the measurements that the UE takes for cell reselection or handover puroposes It is not used for the purposes of the transmission settings but to take the decision (by the UE ndash in case of cell reselection or eNB ndash in case of handover) to move the UE to other cell In the case of handover the UE sends the measurement results according to the eNB commands (eg periodically or triggered by event) The power of the eNB is constant and does not depend on the RSRP RSRQ RSSI measurements

RF optimization

RF (or cluster) optimization starts after all sites in a planned area are installed and verified RF optimization aims to control pilot pollution while optimizing signal coverage increase handover success rates andensure normal distribution of radio signals before parameteroptimization RF optimization involves optimization and adjustment ofantenna system hardware and neighbor lists The first RF optimizationtest must traverse all cells in an area to rectify hardware faults

Preparations for RF Optimization Network plan network structure diagram site distribution siteinformation and

engineering parameters Drive test results (such as service drop points and handoverfailure points) in the current

area Reference signal received power (RSRP) coverage diagram Signal to interference plus noise ratio (SINR) distribution diagram Measured handover success rates Areas to be optimized can be determined by comparing thedistribution of RSRPs SINRs and

handover success rates withthe optimization baseline

• eNB Functionalities

xvi)As contract requirements if the site has other commercial users thethroughput KPI is not must achieved DT team just normally recordthe test result amp the slot occupy rate from NOC M2000 For that thetest is a long term work and the ftp problem is always met as toavoid any delay by the ftp server to all the ftp related test itemsHuawei can use either Mobily ftp server (ftpbayanatcomsa) orHuawei serverxviiHuawei should provide all the original logs when submit the KPIreportsCluster Pre-DriveSystem Check

Get latest cluster drive routes 90 cluster readiness ( You can set whatever readiness your methodology allows for )No major alarms ( From OSS -So you can make sure that OSS team must send a copy of the BTS or eNB alarm reports at the beginning of each day if possible )Ensure the sites in the test clusters are unlocked and put on ldquocell - reservedrdquo Activate the UETR tracing in OSS (if available)

(Letrsquos add one more term make sure to activate UETR for the correct number Check List during Drive

Check that logfiles are active and recording while driving If DLUL sessions stop or hang unexpectedly during testing stop and re-start session Note problematic areas such as those below -

Poor RSCP (lt-100dBm) Poor CINR (lt0dB) Low DL throughput (lt5Mbps) Sites not transmitting even when UE is at close range Swapped feeders (PCI not present at expected coverage area) Laptop UE connection problems etc Take note of inaccessible drive routes Drive round the site in both clockwise and anti-clockwise direction (Onlyapplicable for

single site test)

RSRP of LTE cells(Reference Signal Received Power) RSRP is a RSSI type of measurement It measures the average received power over the resource elements that carry cell-specific reference signals within certain frequency bandwidth RSRP is applicable in both RRC_idle and RRC_connected modes while RSRQ is only applicable in RRC_connected mode In the procedure of cell selection and cell reselection in idle mode RSRP is used RSRP is the LTE equivalent of 3G UMTS RSCPRSRQ of LTE cells ( Re f erence Signal Received Quality) RSRQ is a CI type of measurement and it indicates the quality of the received reference signal It is defined as (NRSRP)(E-UTRA Carrier RSSI) where N makes sure the nominator and denominator are measured over the same frequency bandwidth RSRQ is the LTE equivalent of 3G UMTS Ec N0bullUTRA RSSI The carrier RSSI (Receive Strength Signal Indicator) measures the average total received power observed only in OFDM symbols containing reference symbols for antenna port 0 (ie OFDM symbol 0 amp 4 in a slot) in the measurement bandwidth over N resource blocks The total received power of the carrier RSSI includes the power from co-channel serving amp non-serving cells adjacent channel interference thermal noise etcbullGSM Carrier RSSI This is the RSSI (in dBm) for the signal level of the GSM cells measuredon the UErsquos receiver antenna and compared to a reference level of 1mW

RSRP RSRQ RSSI are the measurements that the UE takes for cell reselection or handover puroposes It is not used for the purposes of the transmission settings but to take the decision (by the UE ndash in case of cell reselection or eNB ndash in case of handover) to move the UE to other cell In the case of handover the UE sends the measurement results according to the eNB commands (eg periodically or triggered by event) The power of the eNB is constant and does not depend on the RSRP RSRQ RSSI measurements

RF optimization

RF (or cluster) optimization starts after all sites in a planned area are installed and verified RF optimization aims to control pilot pollution while optimizing signal coverage increase handover success rates andensure normal distribution of radio signals before parameteroptimization RF optimization involves optimization and adjustment ofantenna system hardware and neighbor lists The first RF optimizationtest must traverse all cells in an area to rectify hardware faults

Preparations for RF Optimization Network plan network structure diagram site distribution siteinformation and

engineering parameters Drive test results (such as service drop points and handoverfailure points) in the current

area Reference signal received power (RSRP) coverage diagram Signal to interference plus noise ratio (SINR) distribution diagram Measured handover success rates Areas to be optimized can be determined by comparing thedistribution of RSRPs SINRs and

handover success rates withthe optimization baseline

• eNB Functionalities

RF (or cluster) optimization starts after all sites in a planned area are installed and verified RF optimization aims to control pilot pollution while optimizing signal coverage increase handover success rates andensure normal distribution of radio signals before parameteroptimization RF optimization involves optimization and adjustment ofantenna system hardware and neighbor lists The first RF optimizationtest must traverse all cells in an area to rectify hardware faults

Preparations for RF Optimization Network plan network structure diagram site distribution siteinformation and

engineering parameters Drive test results (such as service drop points and handoverfailure points) in the current

area Reference signal received power (RSRP) coverage diagram Signal to interference plus noise ratio (SINR) distribution diagram Measured handover success rates Areas to be optimized can be determined by comparing thedistribution of RSRPs SINRs and

handover success rates withthe optimization baseline

• eNB Functionalities