3g radio parameter ericsson

7/22/2019 3g Radio Parameter Ericsson

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3G Ericsson

Radio Parameter

TELKOMSEL

Prepared by Adithya Yudha


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Contents

Idle Mode

Handover

Power Control

Capacity Management

Channel Switching HSDPA


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Idle Mode and Common Channelbehavior


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Cell Selection 3G part

Criteria for Cell Selection

Squel > 0 , Squal = Qqualmeas-qQualMin(only for WCDMA cells) and

Srxlev > 0 , Srxlev = Qrxlevmeas-qRxLevMin- Pcompensation (for all cells)

Pcompensation = max (maxTxPowerUl- P, 0)

Qqualmeas > qQualMin (-18dB) and

Qrxlevmeas > qRxLevMin (-115dBm)- max (maxTxPowerUl(24dB)- P, 0)

qQualMin : indicates the minimum required quality value in the cell. It is sent in

system information, in SIB3 for the serving cell, and in SIB11 for adjacent cells

qRxLevMin :indicates the minimum required signal strength in the cell. It is sent

in SIB3 for the serving cell and in SIB11 for adjacent cells

maxTxPowerUl : indicates the maximum allowed transmission power when the

UE accesses the system on RACH. It is broadcast in SIB3


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Cell Selection 3G part

Qqualmeas (dB)(CPICH Ec/N0)

Qrxlevmeas (dBm)

CPICH RSCP

qQualMin(18)

qRxLevMin

(

115)

Srxlev > 0Pcompensation

Squal > 0Squal >0 AND

Srxlev > 0

suitabl

e

cell?

Squal = Qqualmeas qQualMin

Srxlev = Qrxlevmeas - qRxLevMinPcompensation

Pcompensation = max(maxTxPowerUl P, 0) (dB)


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Cell Reselection 3G partFirst according to S criteria

Squal > 0 (only WCDMA cells)Srxlev > 0

The cells are ranked according to the R criteria:

R(serving) = Qmeas(s) + qHyst(s)

R(neighbor) = Qmeas(n) - qOffset(s,n)

qualMeasQuantity=x

qHyst1: Based on CPICH RSCP

qHyst2: Based on CPICH Ec/No

qHyst(s)

qOffset(s,n)

qOffset1sn: Based on CPICH RSCP

qOffset2sn: Based on CPICH Ec/No

(1 )qHyst(s) and qOffset(sn) based on CPICH RSCP only

(2 ) With this setting the UE first makes qHyst(s) and qOffset(sn)

based on CPICH RSCP . If a GSM cell is highest ranked, no more

ranking is done. If a WCDMA neighbor is highest ranked, a second

ranking takes place, this time according to CPICH Ec/No, and

excluding all GSM neighbors


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Cell Reselection 3G part

R CRITERIA :

R(serving) = Qmeas(s) + qHyst(s)

R(neighbor) = Qmeas(n) - qOffset(s,n)

Note that parameter qOffset1snworks identically for WCDMA-GSM and

WCDMA-WCDMA neighbor relations.

But the values of GSM RSSI and WCDMA CPICH RSCP are not of the same

nature and therefore not directly comparable.

[CPICH RSCP] = [GSM RSSI] + 7

As an example a measured RSCP on a WCDMA CPICH of -100 dBm would becomparable to a GSM broadcast channel RSSI of -93 dBm. A parameter setting

of a GSM neighbor to qOffset1sn= +7 will thus make the received signalstrength in the WCDMA and the GSM cell comparable.


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The decision about when intrafrequency measurements are performed is made using the

sIntraSearch parameter in relation to Squal:

If the Squal > sIntraSearch, the UE does not need to perform intrafrequency measurements.If the Squal sRatSearchand the Srxlev > sHcsRat, the UE does not need to perform measurements on

GSM cells.

If the Squal


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Cell Reselection 3G partMeasurements on GSM Neighbors


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Cell Reselection 3G partFirst ranking of all the cells based on

CPICH RSCP (WCDMA) and RSSI (GSM)

Rs = CPICH RSCP/GSM RSSI + Qhyst1Rn= CPICH_RSCP(n) or RXLEV(n) - Qoffset1

Rn higher in GSM cell

Yes No

Cell re-selectionto GSM

Second ranking only for WCDMA cells based onCPICH Ec/No

Rs = CPICH Ec/No + Qhyst2Rn= CPICH Ec/No -Qoffset2

Cell re-selection toWCDMA cell of highest

R value

GSM cell measurements

available If :CPICH Ec/No qQualMin


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Never-54-70-74-78Always-74-94-98dBm

151410987610Value

If RLA_C < -94 UE starts3G measurements

UE always measures 3Gcells

UE never measures 3Gcells

If RLA_C > -70 UE starts3G measurements

Measurements on 3G Neighbors

The parameters QSI and QSC define thresholds and also indicate whether these

measurements shall be performed when the signal strength (SS) of the serving cell is below or

above the threshold. QSIis used for idle and packet switched modes and broadcast on BCCH

and PBCCH (if enabled), while QSCis used for active mode, sent on SACCH

There are 4 different scenarios to choose from. Parameters QSIand QSCare set per GSM cell and define

both the scenario and the necessary threshold, at the same time:

UTRAN neighboring cells are measured only when the signal strength of the GSM serving cell is abovethe threshold set by QSIand QSC

UTRAN neighbor cells are measured only when the signal strength of the GSM serving cell is belowthethreshold set by QSIand QSC.

UTRAN neighbor cells are always measured.

UTRAN neighbor cells are never measured. This can be used to turn off the cell reselection/handover to

UMTS, per cell, even if COEXUMTSis ON for the BSC.


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Cell Reselection 2G partExample 1: If an UTRAN cell should serve purely to extend the coverage for Multi-

RAT MSs in GSM, it is logical to set QSI /QSC values from 0-6, since it's onlyneeded to make cell reselection and handovers to UMTS when the GSM coverage

falls low.


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Cell Reselection 2G partExample 2: If an UTRAN cell is co-sited with a GSM cell, there is a certain

correlation between signal strengths of the two systems. If the GSM is for exampleusing 900MHz band it is very probable that the GSM signal strength will always be

higher than the UTRAN signal, for a number of dBs. Therefore, there is no point in

measuring UTRAN cells in low GSM signal conditions and values 8-14 can be

selected accordingly.


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Criteria :CPICHEc/No> FDDQMIN(-13dB)and

CPICH RSCP> RLA(s+n)+ FDDQOFF(-infinite)

28240-20-24-28-32

(infinity)

dBm

151483210Value

Always select irrespective of

RSCP value

Reselect in case RSCP > GSM

RXLev (RLA_C) +28dB

FDDQOFF

Value 0 1 2 3 4 5 6 7

dBm -20 -19 -18 -17 -16 -15 -14 -13

FDDQMIN


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Cell Reselection 2G partCell Reselection List

WCDMA

cell

reselectio

n

BCCH: FDDQMIN, FDDQOFF

DEFAULT:

fdd cell reselect offset:

select always

(value is -infinity)

minimum fdd

threshold = -12 dBCheck levels every 5sfrom serving GSM cell

and best 6 GSMneighbour cells

UE starts WCDMA measurements if Rxlevrunning average (RLA_C) is below or above

certain threshold:RLA_C QSI or QSC

UE can select WCDMA cell if the level of theserving GSM and non-serving GSM cells has been

exceeded by certain offset for a period of 5 s:CPICH RSCP > RLA_C+ FDDQOFF

RSCP > (aveRxLev) + -32

UE will re-select WCDMA cell in case it'squality is acceptable:

CPICH Ec/No FDDQMINEcNo -13

Compare levelsof all GSM cells

to WCDMAneighbour

Check qualityof neighbour

WCDMA cells, nopriorities between

WCDMAneighbours

05.0

8:Thismaytakeupto30s

QSI= 7(always)

FDDQOFF= -32 dB

FDDQMIN= -13 dB


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Idle Mode Parameter SummaryCell Selection and Reselection

accessClassNBarredIndicates whether or not access class N is barred ( N = 0 to 15).

0 : not barred

1 : barred

Start from least significatant bit:

bit 0 : class 0

bit 1 : class 1

bit 2 : class 2

.......

bit 15 : class 15

bandIndicatorIndicates the frequency band of the external GSM cell.

The BCCH frequency is unique for all GSM bands except the two GSM

bands DCS1800 and PCS1900, so the band indicator is needed to

discriminate between the two. When the ExternalGsmCell has a BCCHfrequency indicating some other frequency band, then the band

indicator is not needed and may be set to "Not applicable".

bcchFrequency BCCH frequency code in the GSM cell. Contains the absolute radiofrequency channel number of the BCCH channel for the GSM cell. It

uniquely identifies the BCCH.

cellReserved Indicates if this cell shall be reserved for operator use. If it is reserved,there will be no service to the UEs.

fachMeasOccaCycLenCoeffFach Measurement Occasion Cycle Length coefficient. A factor used

when the UE performs inter-frequency and inter-system

measurements. The UE uses this parameter to calculate the interval

length in order to determine the repeating cycle of the measurement.

0 : not broadcasted in SIB 11.

1 : not used.

2 : not used.

3 : used when inter frequency and GSM neighbours.

4 : used when inter freqency or GSM neighbours.

5 - 12 not used.

interFreqFddMeasIndicator Inter-frequency FDD measurement indicator.

FALSE = No

TRUE = Yes


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Idle Mode Parameter SummarymaxTxPowerUl

The maximum UE transmission power on the RACH when accessing

the system. Used in UE functions for cell selection/reselection in idle

mode and connected mode. Also used by UTRAN to control the

maximum TX power level an UE may use.

If the current UE uplink transmit power is above the indicated power

value, the UE shall decrease the power to a level below the power

value. Value launched by System information (SIB11) for each intra-

frequency measurement object corresponding to adjacent cells of

serving cell.

Unit: 1 dBm

Resolution: 1

-50: -50 dBm

...

33: 33 dBm

100 : Default value. The parameter is not sent in SIB11 and the UE will

use the maximum output power for this GSM cell, according to its radio

access capability.

maxTxPowerUl (serving cell, WCDMA neighbor within same RNC)

maxTxPowerUl (WCDMA neighbor belonging to another RNC)

maxTxPowerUl (GSM neighbor)

mccThe MCC part of the PLMN identity used in the GSM radio network.

The PLMN identity consists of two parts:

1. MobileCountryCode, MCC, 3 digits

2. MobileNetworkCode, MNC, 2 or 3 digits

Example: If MCC=125 and MNC=46 then plmnId=12546.

mnc The MNC part of the PLMN identity used in the radio network.

The PLMN identity consists of two parts:

1. MobileCountryCode, MCC, 3 digits

2. MobileNetworkCode, MNC, 2 or 3 digits

Example: If MCC=125 and MNC=46 then plmnId=12546.

nmo Network operation mode that indicates whether the Gs interfacebetween the SGSN and MSC/VLR is installed.

primaryScramblingCode The primary downlink scrambling code to be used in the external cell.


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Idle Mode Parameter SummaryqHyst1

Cell reselection hysteresis used in UE functions in idle and connected

mode. Value launched by System information (SIB3).

Resolution: 2

qHyst2 The hysteresis value of the serving cell. Used to perform cell rankingfor the serving cell.

Resolution: 2

qOffset1sn Signal stength offset between source and target cells. Used when theIE "cell_selection_and_reselection_quality_measure" in SIB 11/12 is

set to "CPICH RSCP". This is configured through

UtranCell::qualMeasQuantity.

Unit: 1 dB

Resolution: 1

-50 : -50dB-49 : -49dB

-48 : -48dB

......

50 : 50dB

qOffset1sn (WCDMA neighbor relation)

qOffset1sn (GSM neighbor relation)

qOffset2sn (WCDMA neighbor relation)

qQualMin Used in UE functions for cell selection/reselection in idle mode andconnected mode. Minimum required (acceptable) quality level in the

cell (dB). Used to set cell border between two cells.

Unit: 1 dB

Resolution: 1

-24 : -24dB

......

0 : 0dB

100 : Indicates that the minimum quality level has not been specified by

the operator. The parameter is then not

present in SIB11 for this neighbour. The UE will use the serving cell

value (UtranCell MO value) instead.

qQualMin (serving cell, WCDMA neighbor within same RNC)

qQualMin (WCDMA neighbor belonging to another RNC)


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Idle Mode Parameter SummaryqRxLevMin

Used in UE functions for cell selection/reselection in idle mode and

connected mode. Minimum required (acceptable) RX level in the cell.

(dBm). Value launched by System information (SIB11) for each intra-

frequency measurement object corresponding to adjacent cells of

serving cell.

Unit: 1 dBm

Resolution: 2

-115 : -115dBm

-113 : -113dBm

-111 : -111dBm

-109 : -109dBm

.....

-25 : -25 dBm

100 : Indicates that the minimum Rx level has not been specified by the

operator. The parameter is then notpresent in SIB11 for this neighbour. The UE will use the serving cell

value (UtranCell MO value) instead.

qRxLevMin (serving cell, WCDMA neighbor belonging to same RNC)

qRxLevMin (WCDMA neighbor belonging to another RNC)

qRxLevMin (GSM neighbor)

qualMeasQuantity Used in UE functions for cell selection/reselection in idle andconnected mode. Cell selection and reselection quality measure.

Value launched by System information (SIB3, SIB11 and SIB12).

sHcsRat RAT specific threshold in the serving cell used in the inter-RATmeasurement rules.

This parameter is used by the UE to decide when to start GSM

measurements for cell reselection, if the serving cell is indicated to

belong to a Hiearachical Cell Structure (HCS)

GSM measurements in idle mode and state CELL_FACH are started

by the UE when RSCP


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Idle Mode Parameter SummarysInterSearch The decision on when measurements on inter frequencies shall be

performed.

If a negative dB value is configured the UE interprets the negative

value as 0 dB.

Unit: 2 dB

Resolution: 1

0 : not sent

1 : -32 dB

2 : -30 dB

...

27 : 20 dB

sIntraSearch The decision on when measurements on intra frequencies shall beperformed.

If a negative dB value is configured, the UE interprets the negative

value as 0 dB.

Unit: 2 dB

Resolution: 1

0 : not sent

1 : -32 dB

2 : -30 dB

...

27 : 20 dB

sRatSearch

The decision on when measurements on GSM frequencies shall beperformed is made using this parameter in relation with Squal.

If S_qual > this parameter, UE need not perform measurements on

GSM cells.

If S_qual


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Idle Mode Parameter SummarytreSelection Control of cell selection/reselection. Time-to-trigger for cell reselection

in seconds.

Value launched by System information (SIB3).uarfcnDl Downlink Utra Absolute Radio Frequency Channel Number.

Specifies the channel number for the central DL frequency. The

mapping from channel number to physical frequency is described in

3GPP specification TS 25.104.

Unit: Channel number

Resolution: N/A

uarfcnUl Uplink Utra Absolute Radio Frequency Channel Number.

Specifies the channel number for the central UL frequency. The

mapping from channel number to physical frequency is described in

3GPP specification TS 25.104.

Unit: Channel number

Resolution: N/A


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Idle Mode Parameter SummaryLocation and Routing Area Updating

att Indicates to the UE whether IMSI attach/detach is allowed. (SomeIMSIs are not allowed in some LAs.) This helps to facilitate the

avoidance of unnecessary paging attempts. The value is sent on theBCCH.

FALSE: IMSI attach not allowed

TRUE: IMSI attach allowed

lAC The Location Area Code of the external GSM cell.

Note: the values 0000 and FFFE are reserved for special cases where

no valid LAI exists in the MS.

Old name: lAC

rAC Routing Area Code of a routing area. An RA is used by UTRAN to pagemobiles on request from the PS CN.

When the parameter is changed, UTRAN shall update system

information and notity UEs.

Old name: rAC

t3212 Periodic update timer for LA update.

Unit: 0.1 hours (= 1 decihour = 6 minutes = 360 seconds)

Resolution: 1

0 means infinite time, i.e. not


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Idle Mode Parameter SummaryPagingcnDrxCycleLengthCs Core Network DRX cycle length coefficient (k) for UEs in idle mode,

circuit switched.

The cycle length is calculated as the k'th potential of 2, where k = 6..9.

For example, 6 corresponds to cycle length 640 ms, 7 corresponds to

cycle length 1280 ms, etc.

cnDrxCycleLengthPs Core Network DRX cycle length coefficient (k) for UEs in idle mode,packet switched.

The cycle length is calculated as the k'th potential of 2, where k = 6..9.

For example, 6 corresponds to cycle length 640 ms, 7 corresponds to

cycle length 1280 ms, etc.

noOfMaxDrxCycles Paging notification duration.

To notify UEs in IDLE mode about a system information update, the

RNC sends a paging message on the PCH at every page occasion of a

number of maximum DRX cycles.

noOfPagingRecordTransm Number of preconfigured subsequent transmissions of the samePaging Record.

System Information

noOfMibValueTagRetrans Number of MIB value tag retransmissions on the FACH.

sib1PlmnScopeValueTag The area identity part of PLMN scope value tages for SIB1

sib1RepPeriod

sib3RepPeriod

sib5RepPeriod

sib7RepPeriod

sib11RepPeriodsib12RepPeriod

sib1StartPos

sib3StartPos

sib5StartPos

sib7StartPos

sib11StartPos

sib12StartPos

sib7ExpirationTimeFactor SIB7 use expiration time as re-read mechanism. The expiration time issib7RepPeriod times sib7ExpirationTimeFactor.

updateCellReattsNo Number of update reattempts when an update of system informationparameters in a cell failed.

Idle Mode Behaviour


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UE States

Idle mode No connection to radio network (No RRC connection established)

This minimizes resource utilization in UE and the network

CELL_FACH mode

User Equipment (UE) in Connected Mode (has an RRC Connection toradio network)

UE uses the common transport channels RACH or FACH

If the parameter interFreqFDDMeasIndicator = 1, the UE will evaluate cell

reselection criteria on inter-frequency cells (0)

CELL_DCH mode

User Equipment (UE) in Connected Mode (has an RRC Connection to

radio network)

UE uses dedicated channels for transmitting data and signalling

Idle Mode Behaviour


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Power Control


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primary CPICH power should be 8 to 10% (~ 1 Watt) of

the nominal RBS power at the reference point (~10W,while MCPA is 20W)

The pilot power is designed to be equal in all cells at the

Reference Point.

primaryCpichPower = 30 dBm

TopOfRack =primaryCpichPower +

dlAttenuation

System will adjust the TopOfRack to meet the requiredvalue.

Consistency check on

MaximumTransmissionPowerDL (Calculated vs.

setting value)

The feeder loss parameters ulAttenuation &

dlAttenuation and electrical delay parameters

ulElectricalDelay & dlElectricalDelay must be enteredproperly in the system (actual VSWR).

More CPICHless capacity trade off TopOfRack

P-CPICH

MaxTxPowerDL

dl/ulAttenuation

dl/ElectDelay

Pilot Channel Power


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Common Control Channel Power

With increasing CPICH powercapacity directly decreasis, but common channels and

power per each dedicated channel is calculated from CPICH

At CPICH 30 dBm, the common channel will be configured as follow:

Parameter Name MO Type Value Cumm(dBm) Peak Power(W) Typical AF Avg Power(W)

primaryCpichPower UtranCell 30 1 1 1

pchPower Pch -0.4 29.6 0.91 0.20 0.18

primarySchPower UtranCell -1.8 28.2 0.66 0.10 0.07

secondarySchPower UtranCell -3.5 26.5 0.45 0.10 0.04

maxFach1Power Fach 1.8 31.8 1.51 0.10 0.15

maxFach2Power Fach 1.5 31.5 1.41 0.30 0.42

bchPower UtranCell -3.1 26.9 0.49 0.90 0.44

aichPower Rach -6 24 0.25 0.10 0.03

pichPower Pch -7 23 0.20 1.00 0.20

38.38 6.89 2.53

MaximumTransmissionPowerDL is design to be equal with Nominal RBS Power


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Common Channel on Downlink

Cell Setup and Reconfiguration - DownlinkprimaryCpichPower is the power used for transmitting the PCPICH.

bchPower is the power used for transmitting on the BCH, relative to the primaryCpichPower value.

primarySchPower is the power used for transmitting on the Primary SCH, relative to the primaryCpichPower value.

secondarySchPower is the power used for transmitting on the Secondary SCH, relative to the primaryCpichPower value.

Common Transport Channel Setup and Reconfiguration - DownlinkaichPower is the power used for transmitting on AICH, relative to the primaryCpichPower value.

maxFach1Power defines the maximum power used for transmitting the first FACH channel, relative to the

primaryCpichPower value. The first FACH is used for logical channels BCCH, CCCH, and DCCH

control si nalin .maxFach2Power defines the Maximum power used for transmitting the second FACH channel, relative to the

primaryCpichPower value. The second FACH is used for logical channel DTCH traffic signaling.pOffset1Fach is the offset between downlink DPDCH and DPCCH TFCI field on FACH.

pOffset3Fach is the offset between downlink DPDCH and DPCCH pilot field on FACH.

pchPower is the power used for transmitting on the PCH, relative to the primaryCpichPower value.

pichPower is the power used for transmitting on the PICH, relative to the primaryCpichPower value.


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Common Channel on UplinkCommon Transport Channel Setup and Reconfiguration - UplinkconstantValueCprach is a constant value in dB used by the UE to calculate the initial power on the PRACH according to

the Open Loop Power Control procedure.

powerOffsetP0 is the Power ramp step for the preamble when no acquisition indicator is received.powerOffsetPpm is the Power offset between the last transmitted preamble and the control part of the random

access message.preambleRetransMax is the maximum number of preambles sent in one RACH preamble ramping cycle.

maxPreambleCycle is the maximum number of preamble ramping cycle.


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Common Channel on Uplink

P_RACH

The initial power on the PRACH - the power of the first preamble - is determined according to equation

P_PRACH = L_PCPICH + RTWP + constantValueCprach(-27dB)

L_PCPICH : is the path loss estimated by the UE based on knowing thetransmitted and received PCPICH power.

RTWP : is the Received Total Wideband Power (uplink interference) level

measured by the RBS.constantValueCprach : is used by the UE to calculate the initial power on the PRACH . This

parameter is configurable and decides at which level below RTWPpreamble ramping will start


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POWER RAMP ON RACH

To reach an appropriate received power level at the RBS, the UE uses preamble ramping. This

procedure consists of the following steps:

The UE transmits a preamble.

As soon as the RBS properly detects the preamble, it sends an Acknowledgement Indicator

(AI) on the AICH.

While not receiving any AI, the UE transmits a new preamble, increasing the transmission

power with respect to the previous one by the configurable parameter powerOffsetP0.(3dB)

As soon as the UE receives an AI, it sends the PRACH message part. The power of the

control part of the random access message is determined by the power of the last

transmitted preamble and by a configurable offset powerOffsetPpm.(- 4dB)The power of

the data part of the PRACH message is determined by the gain factors for PRACH, which isincluded in System Information.


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Common Channel on UplinkPOWER RAMP ON RACH

preambleRetransMax (8) parameter determineshow many times PRACH preamble can be sent

within one preamble ramping cycle (SIB5&6)

maxPreambleCycle (4) defines how many timesthe PRACH preamble ramping cycle procedure canbe repeated before UE MAC reports a failure on

RACH transmission to higher layers (SIB5&6)


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In average coverage conditions the RRC Connection Setup performance can be improved by tuning theopen loop power control parameters

These parameters are

preambleRetransMax and& maxPreambleCycle

powerOffsetPpm

powerOffsetP0

maxPreambleCycle# preamble power ramping cycles that can be done

before RACH transmission failure is reported

Downlink

BS

L1 ACK / AICH

Uplink

MS Preamble1

Not detected

Message partPreamble2

Preamble

preambleRetransMax# PRACH preambles transmitted during one PRACH

cycle without receiving AICH response

MaxTXPowerUl

powerOffsetP0

powerOffsetPpmInitialpreamblepower


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Handover


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Soft/Softer Handover

Inter-Frequency Handover

Inter-RAT Handover

Inter-RAT Cell Change

HSDPA Mobility


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Intra-Frequency Handover

SOFTER HANDOVER

MS simultaneously connected to multiple cells (handled by same BTS)

No extra transmissions across Iub interface Mobile Evaluated HandOver (MEHO)

Both UL and DL: Maximum Ratio Combining (MRC) is occurring in rake receiver

SOFT HANDOVER

MS simultaneously connected to multiple cells (from different BTSs)

Extra transmission across Iub, more channel cards are needed

Mobile Evaluated HandOver (MEHO)

DL/UE: MRC

UL/RNC: Frame selection combining

HARD HANDOVER

Arises when inter-RNC SHO is not possible (Iur not supported or Iur congestion)

Decision procedure is the same as SHO (MEHO)

Causes temporary disconnection

Inter-Frequency Handover

Can be intra-BS, intra-RNC, inter-RNC

Network Evaluated HandOver (NEHO)

Inter-RAT (Inter-system) Handover

Handovers between GSM and WCDMA (NEHO)


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Entities Involved in Reporting, Evaluation, and Execution of Handover-Related Functions.

The concept of event-triggered reportingas specified in 3GPP is used by handover evaluationand

allows the UE to do some part of the evaluation.

Thus, the UE is configured to evaluate and send measurement reports to the system only when certain

events occur, that is, when a monitored cell is measured and the measurement result for a monitored cell

fulfills certain criteria. When the conditions for triggering a certain handover are fulfilled, the handoverevaluation part triggers the corresponding handover execution part.

Entities Involved in Reporting, Evaluation, and Execution of Handover-Related Functions.


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3GPP-defined UE Associated Cell sets for Measurement

Active Set

The cells involved in soft handover and measured by the UE

Virtual Active Set

The Active Set associated with a non-used frequency for support of Inter-Frequencyevaluation

Monitored Set

The cells only measured by the UE and not part of the Active Set. The monitored set can

consist of intra-frequency, Inter-Frequency and Inter-RAT cells

Detected Set

The intra frequency cells(P-CPICH scrambling codes) detected by the UE but not part of

Active Set or monitored set


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Event 1a, A primary CPICH enters the Reporting Range(measured P-CPICH Ec/No) > (P-CPICH Ec/No of the Best Cell in the Active Set) -

reportingRange1a + hysteresis1a /2

Event 1b, A primary CPICH leaves the Reporting Range

When a P-CPICH, not included in the Active Set, enters reportingRange1a + hysteresis1a/2, and the

measured value remains in reportingRange1a + hysteresis1a/2at least a time equal to timeToTrigger1a

(Time to Trigger 1a), event 1a occurs. The UE sends a MEASUREMENT REPORT message for event 1a to

the SRNC. If the report contains more than one cell fulfilling 1a criteria, only the one with highest Ec/No isconsidered and retained. If the retained cell is a valid celland Active Set is not full (present cells in the

Active Set is less than maxActiveSetparameter), the cell is proposed to be added to the Active Set. If

the Active Set is full, the cell is proposed as a replacement of the worst cell in the Active Set provided that the

reported cell has a better quality than the worst cell in the Active Set.

(measured P-CPICH Ec/No) < (P-CPICH Ec/No of the best cell in the Active Set) -

reportingRange1b - hysteresis1b /2

When a P-CPICH, included in the Active Set, leaves reportingRange1b - hysteresis1b /2, and the

measured value is outside reportingRange1b - hysteresis1b /2during a time at least equal to

timeToTrigger1b, event 1b occurs. The UE sends a MEASUREMENT REPORT message for event 1b to the

SRNC. The handover algorithms will remove the reported cells one by one from the Active Set, however onecell is always kept in the Active Set for maintaining the connection.


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Cell (P_CPICH2) Would

be proposed to be

included in Active Set

List


be proposed to be

excluded from Active

Set List

Event 1a and Event 1b

6dB10d

320 ms 640 ms


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Event 1c, A non-active primary CPICH becomes better than an Active PrimaryCPICH


When a P-CPICH, not included in the

Active Set, becomes stronger than the

weakestP-CPICH+hysteresis1c /2in the Active

Set during a time at least equal to

timeToTrigger1c,and the Active Set is full

(present cells in the Active Set is equal to

maxActiveSetparameter) event 1c

occurs. The UE sends a

MEASUREMENT REPORT message for

event 1c to the SRNC. If the retained cellis a valid cell, and the Active Set is full,

the cell is proposed as a replacement for

the weakest cell in the Active Set

(measured P-CPICH Ec/No) > (P-CPICH Ec/No of the Best Cell in the Active Set) +

hysteresis1a /2


be replaced P_CPICH3

in active set list

Hysteresis1c (2dB)

320 ms


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Soft/Softer HandoverParameter Summary

Setting Value Remark

reportingRange1a 6 3 dB

reportingRange1b 10 5 dB

timeToTrigger1a 11 320mstimeToTrigger1b 12 640ms

timeToTrigger1c 11 320ms

timeToTrigger1d 14 2560ms

hysteresis1a 0 0

hysteresis1b 0 0

hysteresis1c 2 1dB

hysteresis1d 15 7dB

maxActiveSet 3 3


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Inter-RAT Handover

Event 2d, The Estimated Quality of the Currently Used frequency is below a

Certain Threshold

When the estimated quality of the current WCDMA RAN used frequency is below the absolute threshold

usedFreqThresh2dEcno - hysteresis2d/2, during a time at least equal to timeToTrigger2dEcno, ORtheestimated quality of the current WCDMA RAN used frequency is below the absolute threshold

usedFreqThresh2dRscp - hysteresis2d/2, during a time at least equal to timeToTrigger2dRscp, event 2d

occurs.

Event 2f, The estimated quality of the currently used frequency is above a

certain threshold

When the estimated quality of the current WCDMA RAN used frequency is above the relative threshold

usedFreqRelThresh2fEcno+usedFreqThresh2dEcno + hysteresis2f/2, during a time at least equal to

timeToTrigger2fEcno,ANDthe estimated quality of the current WCDMA RAN used frequency is above therelative threshold usedFreqRelThresh2fRscp+usedFreqThresh2dRscp + hysteresis2f/2, during a time at

least equal to timeToTrigger2fRscpevent 2f occurs. The UE sends a MEASUREMENT REPORT message

for event 2f to the SRNC. When SRNC receives the MEASUREMENT REPORT message for event 2f from

the UE, measurements for IRATHO_eval event 3a or IFHO_eval event 2b and associated compressed mode

usage is stopped.


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Inter-RAT Handover

UE start compressed

mode to measure GSM

or Interfreq Neighbors

UE stop compressed

mode

-12 dB

1 + (-12 dB)

640 ms 2560 ms

Compressed Mode and de-Compressed Mode


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Event 3a, The Estimated Quality of the Currently Used UTRAN Frequency isbelow a Certain Threshold and the Estimated Quality of the Other System is

above a Certain Threshold

The event 3a occurs according to the following points:

When the estimated quality of the WCDMA RAN used frequency is below the threshold

usedFreqThresh2dEcno+utranRelThresh3aEcno - hysteresis3a/2andthe measured GSM carrier RSSI ofa GSM/GPRS cell is above the absolute threshold gsmThresh3a, during a time at least equal to

TimeToTrigger3a

when the estimated quality of the WCDMA RAN used frequency is below the threshold

usedFreqThresh2dRscp+utranRelThresh3aRscp - hysteresis3a/2andthe measured GSM carrier RSSI of

a GSM/GPRS cell is above the absolute threshold gsmThresh3a, during a time at least equal to

TimeToTrigger3a

in case of the connection quality has been triggered in UL for UE TX power (event 6a, see Event 6a, The UE

Tx Power becomes larger than an Absolute Threshold), the event 3a is triggered when the estimated quality of

the WCDMA RAN used frequency is below the threshold

usedFreqThresh2dRscp+utranRelThresh3aRscp+utranRelThreshRscp - hysteresis3a/2andthe

measured GSM carrier RSSI of a GSM/GPRS cell is above the absolute threshold gsmThresh3a, during a

time at least equal to TimeToTrigger3a.

Inter-RAT Handover


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Inter-RAT Handover

(-12 dB) + (-1dB)

RSSI -95dB

320 ms

IFHO & IRAT Parameter Summary


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IFHO & IRAT Parameter Summary

WCDMA to GPRS (PS)


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WCDMA to GPRS (PS)

3G-SGSN

SRNC BSC

2G-SGSN

GGSN

RBSRBS

RBS RBS

RBS

RBS

Iu Gb

AbisIub

GnGn

External

Networks

Gi

A successful IRATCC from


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SRNCCN/SGSN Target BSS

CELL_DCH

1. DCCH (AM) Measurement Report (Event 2d)

2. Evaluation of MR

3. Compressed Mode Control

4. DCCH (AM) Measurement Control

5. DCCH (AM) Measurement Report (Event 3a)

6. Evaluation of MR

7. DCCH (AM):CELL_DCH Cell Change Order from UTRAN

8. GSM: RA Update

10. Stop DL Transmission

12. Iu Release Command

14. Iu Release Complete

13. Dedicated Radio Link Release

A successful IRATCC from

WCDMA to GPRS

9. SRNS Context Request

11. SRNS Context Response


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GSM to WCDMA (voice) :

Measurements on WCDMA CellsFour different scenarios:

WCDMA RAN neighbor cells are measured only when the signal strength of theGSM serving cell is above the threshold set by QSI and QSC.

WCDMA RAN neighbor cells are measured only when the signal strength of theGSM serving cell is belowthe threshold set by QSIand QSC.

WCDMA RAN neighbor cells are always measured.

WCDMA RAN neighbor cells are never measured.This can be used to turn off the cell reselection/handover to WCDMA, per cell,

even if COEXUMTS(parameter used to activate the functionality of makinghandovers and cell reselections between GSM and WCDMA) is on for the BSC.


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Load sharing

Load sharing


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Load sharing

Load sharing to 2ndcarrier at RRC establishment

Least loaded cell (Highest difference between power and pwradm) is

chosen by sending RRC connection reject with redirection info to 2nd

carrier.

Directed Retry to GSM at RAB establishment

When Dl power reaches loadSharingGsmThreshold percentage of

pwradm, calls are targeted to be offloaded to GSM. This is achieved

by rejecting RAB establishment requests with directed retry as acause.

Load sharing capabilities


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Load sharing capabilities

available in the WCDMA RAN

Inter Frequency Load Sharing


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Inter-Frequency Load Sharing


At call set-up - RRC Connection Establishment for allRABs

Triggered by Downlink Transmitted Carrier Power*(load on source > 50% andload on target less thansource by a 10 % margin)

The feature is activated in an RNC by setting the

parameter loadSharingRrcEnabled to TRUE

The attribute loadSharingCandidate TRUE/FALSE

specifies whether the target cell is a load-sharing neighbor

of the source cellf1 f1f1 f1

f2 f2

*Not operator configurable



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Inter Frequency Load Sharing

(RRC redirection) (Extra Slide)

RNC

RRC Connection RequestCCCH/RACH

RRC Connection Reject CCCH/FACH

Idle

Mode

Cell selection

on designated

UTRA carrier

RRC Connection RequestCCCH/RACH

RRC Connection SetupCCCH/FACH

F1

F2

Includes Frequency

Info IE

2ndwill not be

redirected but maybe successful or

rejected due to

congestion

Directed retry to GSM


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Directed retry to GSMApplicable for voice in P3

WCDMA

GSM

Admission

Control

Directed retry to GSM


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Directed retry to GSM Directed retry to GSM

At call set-up - RAB Establishment for voice

Triggered by Downlink Transmitted Carrier Power

The feature is activated in an RNC by setting the parameter

loadSharingDirRetryEnabled to TRUE

One GSM target can be defined for each WCDMA cell via the cell

parameter directedRetryTarget

loadSharingGsmThreshold specifies the minimum load at which off-

loading to GSM begins: ex 80% of pwrAdm

loadSharingGsmFraction specifies the percentage of Directed Retry

candidates to be diverted to GSM while the cell load is above the

specified load threshold

Directed Retry to GSM


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Directed Retry to GSM

UE RBS/RNC CN

Directed Retry

decision to send

Successful

access to GSM

Contacts GSM

cell and orders

relocation

HO from UTRAN command

RAB Assignment Request

RAB Assignment Response (failed, cause=directed retry)

Relocation Required

Relocation Command

Iu release Command

Iu release Complete

Voice calls can be relocated to GSM due to high load in WCDMA

If the call is not accepted in GSM - try in WCDMA again!

Load balancing for voice between


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When out of coverage, theWCDMA voice call is handed

over to GSM

When GSM load reaches acustomizable threshold, voice calls can

be handed over to WCDMA

GSM coverage

Dual Mode UE

GSM terminal

Load balancing for voice between

WCDMA-GSM

Load based handover to GSM

during call set up, Directed Retry

(P3) to GSM

IntroductionFeatures & Roadmap

WCDMA coverage


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Channel Switching

Channel Switching


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Channel Switching Parameter Summary

Channel Switching


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1. Common to Dedicated Evaluation

Monitors if the UE shall be switched from a common to a dedicated transport

channel due to large amount of user data buffered in the RNC or the UE.

2. Dedicated to Dedicated Up-Switch Evaluation

Monitors if the throughput becomes close to the max user bandwidth and switch to

the next higher bitrate radio bearer is required.

2a. Dedicated to Dedicated Coverage triggered Down-Switch Evaluation

Monitors if a switch to a lower rate radio bearer is required due to coverage.

3. Dedicated to Common Evaluation

Monitors if a switch from a Cell_DCH to Cell_FACH is required due to a decreasein transmitted user data.

4. Common to Idle Evaluation

Monitors if a switch from Cell_FACH to Idle mode is required due to a complete

lack of user data transmission.

Channel Switching


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Multi-RAB Down-switch Evaluation

Monitors if a release (or downswitch) of PS I/B RAB shall be initiated due to lack ofPS data throughput (zero), resulting in a single speech 12.2 kbps (or speech + PS

0/0) or CS64 RAB.

Multi-RAB Up-switch Evaluation

Monitors if an upswitch from multi-RAB SP0 to multi-RAB SP64 shall be initiateddue to data buffered in either RNC or UE.

Channel Switching


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Future releases

activity/inactivity-based

switching UL and/or DL

DL throughput-

based upswitch

UL throughput-

based upswitch

coverage-triggered

downswitch (DL only)

choice based on UE-

and cell-capability

IDLE

FACH

DCH

HS384/HS

64/384

64/HS

64/128

64/64

128/128

stand-alone interactive RAB

speech

+ 0/0

speech+ 64/64

speech

+ 64/HS

speech

+ 384/HS

speech + interactive

RAB

PS RAB Establishment

Low/No RLC buffer load for

Inactivity timer period

Low/No throughputMeasurement for down

Switch timer period


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Capacity Management

Admission control workflow


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Resource request Is admission blocked

by Congestion Control?

Yes,

then

block

Check if the requested

ASE UL + estimated ASE UL

>

aseUlAdm

No

Yes,

then

block


DL Pwr + estimated Pwr

>

pwrAdm

No

Yes, then block

Check if the requested +

estimated # compressed mode RL

>

compModeAdm

No

Yes,

then

block

No, then

accept


ASE DL + estimated DL ASE

>

aseDlAdm

No

Yes,

then

block

Yes,

then

block


code usage + estimated code usage

>

dLCodeAdm

No

No

Yes,

then

block


DL SF + estimated DL SF

>

sfXAdm*

Only checked ifBE-service requests

X = 8 or X = 32

X = 16

75*

160*

240*

SF8adm= 8*

SF16adm= 16*

SF32adm= 32*

70*

15*

* Currentdefault values

Soft Congestion mechanism


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Soft Congestion mechanism

New request for ng 64/128, ng 64/64 or g access

Admission Control blocks the new request

An existing ng user of 64/384 will be switched down to 64/128

or an existing ng user of 64/128 will be switched down to 64/64

Spreading Factor (SF) limits


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p g ( )

used in Admission Control

8* 16*32*

* Current default values

ASE release order


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Core Network

SRNC &DRNC

Iu

Iur

over Iur:

SRNC

Iu

over Iu:

1. Non-guaranteed service

class connections

3. CS/streaming service

class connections

5. Speech users

2. Non-guaranteed service

class connections

4. CS /streaming service

class connections

6. Speech users


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HSDPA


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HSDPA Parameter Summary

Parameter Name Default Value Initial Setting TELKOMSEL

HSPATHLOSSTHRESHOLD 170 170

CQIERRORSABSENT 10 10

HSPOWERMARGIN 2 2

HSSCCHMAXCODEPOWER -20 -20

QUEUESELECTALGORITHM ROUND_ROBIN ROUND_ROBIN

SUPPORTOF16QAM FALSE TRUE

MAXHSRATE 15 30

HSONLYBESTCELL 1 1

HSHYSTERESIS1D 10 10

HSQUALITYESTIMATE CPICH_RSCP CPICH_RSCP

HSTIMETOTRIGGER1D 640 640


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MAXHSRATE

The HSDPA Iub flow control algorithm adjusts the available bit rate over Iub based mainly on themaximum possible air interface bitrate received from the scheduler, the number of users in a celland Iub congestion indications. The RBS uses the parameter maxHsRate to determine themaximumbit rate to be used for HS-DSCH data frame traffic in one aggregated bit pipe over Iub.

The parameter maxHsRate should be configured for each RBS to represent the maximum MAC-dPDU bitrate of HS-DSCH data frames, which is available for the AAL2 path or paths carrying

HSDPA traffic to the RBS in question. The parameter may be set to a MAC-d PDU bit rate of 1.5Mbps (the default value), when one dedicated physical E1 link is used for HSDPA traffic. Thismaximum bitrate level is the same as the bitrate expressed by the CAPACITY ALLOCATIONcontrol frames.

As an example, the default value of this parameter has been obtained by multiplying the HSDPAavailable ATM bandwidth (excluding IMA overhead), e.g. 1.92 Mbps, with a factor of 0.79. Thisfactor is dependent on the average number of MAC-d PDUs per HS-DSCH data frame. In thiscase, it is based on having 10 MAC-d PDUs (336 bits) per HS-DSCH data frame in average. Itshould be noted that assuming a lower number of PDUs per data frame gives a lower factor andvice versa.

The parameter value of maxHsRate also depends on how the transport network is configured, e.g.if ATM VC Cross Connect is used or if AAL2 switching is used. It depends on how the ATM VCsetc are configured, e.g. for HS traffic only, sharing with AAL2 class A and B, several AAL2 pathsfor HS etc. Therefore it is recommended to follow the guidelines given by Ericsson regardingtransport network dimensioning before setting a value for this parameter.


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16QAM Modulation

The RBS hardware supports both QPSK and 16QAM modulation. However, support of 16QAM is

an optional feature which can be configured on cell level using the parameter supportOf16qam.

The available modulation type impacts the maximum achievable bit rate in the cell,

Maximum Achievable User Bit Rate at the RLC Level As a Function of the UE HS-DSCH Category and Modulation Type

3g radio parameter ericsson

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