38204187 gprs edge network planning and optimization chapter4 radio parameters 20040524 a 1 0

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GPRS/EGPRS Radio Parameters

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GPRS/EDGE Radio Parameters For internal use only

Table of Contents

Chapter 4 GPRS Radio Parameters ..................................................................................... 4 4.1. GPRS Cell Parameters ............................................................................................... 4

4..1.1. Option Parameters .......................................................................................... 4 4..1.2. GPRS Cell Access Control Parameters ........................................................ 12 4..1.3. Power Control Parameters ............................................................................ 23 4..1.4. GPRS Cell Identity ........................................................................................ 31 4..1.5. GPRS Cell Reselection Parameters .............................................................. 32 4..1.6. Measurement Report Control Parameters ................................................... 38 4..1.7. CS Change and Control Parameters ............................................................ 43

4.2 GRPS MM Parameters ............................................................................................ 45 4.2.1 GMM Timer ................................................................................................... 45 4.2.2 BSSAPP Timer Parameters .......................................................................... 46

4.3 GPRS Session Management Parameters ............................................................... 47 4.3.1 Introduction to Session Management Function ............................................. 47 4.3.2 SM Parameters Optimization ........................................................................ 47

2005-11-03 All rights reserved Page3 of 53


Chapter 4 GPRS Radio Parameters

This chapter introduces parameters in the configuration for GPRS cells and Gb interfaces, and their effect on radio functions and flow control at Gb interface.

4.1. GPRS Cell Parameters

4..1.1. Option Parameters

GPRS cell option parameters control the GPRS-related cell options, and they can be sent by SI13, PSI1, PSI13, and PSI14. These parameters include network mode of operation (NMO), T3168, T3192, DRX_TIMER_MAX, ACCESS_BURST_TYP, CONTROL_ACK_TYPE, BS_CV_MAX, PAN_DEC, PAN_INC, PAN_MAX, and T3193. Descriptions of them are as follows.

4.1.1.1. NMO

I. Definition and Format

NMO is related with paging channels used in a GPRS system. It includes NMOI, NMOII, and NMOIII

When Gs interface is configured in the GPRS network, NMOI is required.

When no Gs interface and no PCCCH are configured in the GPRS network, NMOII is required.

When no Gs interface but a PCCCH is configured in the GPRS network, NMOIII is required.

II. Setting and Effect

The same NMO must be configured for the cells in the same routing area (RA).

4.1.1.2. T3168


T3168 controls the time of an MS waiting for a Packet Uplink Assignment message. The T3168 starts when an MS sends a Packet Resource Request message and waits for the Packet Uplink Assignment message, or sends a Packet Control Acknowledgement message for a new Temporary Block Flow (TBF). The T3168 decides when to stop waiting for the Packet Uplink Assignment message.



T3168 is coded according to the following table.

T3168 codingT3168 Value (ms)

0 5001 1000

10 150011 2000

100 2500101 3000110 3500111 4000

When the timer expires, an MS restarts the packet access. The MS reports an RLC/MAC Error to the upper layer after sending a Packet Resource Request message for four times and TBF establishment fails.


Values of T3168 affect the success rate of TBF establishment. The shorter the value is, the less the time for the TBF establishment is. Therefore, when the radio environment is poor, the success rate of TBF establishment is lower. Whereas the longer the value is, the longer the period for the MS to judge TBF establishment failure is. Thus, the delay time for the packet access is longer and the system performance decreases.

The effect of radio environment (namely, BLER of signaling message) must be considered in the setting of T3168. The setting is as follows:

If BLER < 2%, that is, the radio environment is very good, the T3168 is set to 500ms.

If 2% < BLER < 5%, that is, the radio environment is relatively good, the T3168 is set to 1000ms.

If 5% < BLER < 10%, that is, the radio environment is poor, the T3168 is set to 2000ms.

4.1.1.3. T3192


T3192 controls the time of an MS waiting for the TBF release after the MS receives the last data block. T3192 is coded according to the following table. The value 0 means that the timer expires without starting.

T3192 Value (ms)

000 500



001 1000

010 1500

011 0

100 80

101 120

110 160

111 200

An MS starts T3192 when sending a Packet Downlink Ack/Nack message (FAI = 1) to the network, or sending a Packet Control Ack message as a response to the last data block in an unacknowledged mode.

When the starting conditions are met, the T3192 starts.

When receiving a Packet Downlink Assignment message or a Packet Timeslot Reconfigure" message from PCU, the MS stops the T3192.

If the T3192 expires, the MS releases the TBF-related resources related and begins to intercept paging channels. This parameter is configured by 500ms.

If the MS works in a semi-duplex mode and receives a Packet Uplink Assignment message during the TBF release, the MS responds to this command at once.

If the MS does not receive the Packet Uplink Assignment message, it works in a packet idle mode or a dedicated mode in the case of dual transfer mode.

According to the 3GPP protocols, the MS still must work in a non-DRX mode for a period when the MS works in an idle mode or a dedicated mode.

Note:

Dual transfer mode means that CS services and PS services are performed at the same time with the support of MSs.


The longer the value of this parameter is, the longer the time for reserving TBF-related resources. The resources include TFI and timeslot. Therefore, sending the same TBF takes longer, and the network congestion is present easily.

The shorter the value of this parameter is, the longer the TBF establishment, because an MS releases the TBF resources quickly. If the network has new downlink data, it initiates a paging or immediate assignment flow (the MS is in Ready state).

If the T3192 expires before the new downlink data is present in the network side, the network sends a Packet Downlink Assignment message directly to establish



a new downlink TBF to shorten TBF establishment time.

The service load and mode of a cell must be considered in the setting of this parameter. If there are enough network resources, the T3192 is set to a larger value as possible to shorten the TBF establishment time and improve the data transmission rate.

T3193 is configured at the corresponding network side, and the time length of the T3193 must be longer than that of the T3192.

4.1.1.4. DRX_Timer_Max


This parameter controls the maximum time of the MS working in a non-DRX mode in the case of a packet transmission mode transition to a packet idle mode.

This parameter is represented in binary, and ranges from 0 to 7. The parameter value is represented as 2 (k - 1) , in a unit of 1 second. When K is set to 0, this parameter value is 0, namely, this parameter can be 0s, 1s, 2s, 4s, 8s64 s..

When an MS transits to a packet idle mode from a packet transmission mode, it works in a non-DRX mode for a period. After the TBF resources are released, the MS monitors all CCCH blocks. Meanwhile, the PCU reserves MS-related contexts. The minimum value of the Non_DRX_Timer and DRX_Timer_Max decides the reservation time.


When no PCCCH is configured in the network, an MS takes 40ms to send an Immediate Assignment Command on PCH and AGCH in a non-DRX mode. But an MS takes more time to send this message in a DRX mode. Therefore, when an MS works in a non-DRX mode, the TBF establishment takes the less time. .

In a DRX mode, an MS can only monitor paging messages in its paging group, and then receives the Immediate Assignment message on all paging channels and AGCH reserved blocks. As a result, an MS takes a long time to receive the paging messages, and the average time is about a half of paging multi-frame period. When the BS_PA_MFRMS is 2, the average time is 235ms.

In a non-DRX mode, the MS consumes more power. Therefore, when the value of DRX_Timer_Max is great, the time for TBF establishment is shortened but the MS consumes more power. When the value of DRX_Timer_Max is small, the MS consumes less power. However, when an MS works in a DRX mode, a paging flow is added, the signaling load of system and the delay for data transmission increase.



4.1.1.5. ACCESS_BURST_TYPE


This parameter means an MS uses an 8-bit or 11-bit format in a PACKET CHANNEL REQUEST message, the PTCCH Uplink Block message and in PACKET CONTROL ACKNOWLEDGMENT message when four access bursts are used.

This parameter is represented by 1bit. 0 means that 8-bit format is used, and 1 means that 11-bit format is used.

4.1.1.6. CONTROL_ACK_TYPE


This parameter sets the default format used by an MS in a PACKET CONTROL ACKNOWLEDGMENT message.

This parameter is represented by 1bit. 0 means that the four access bursts format, and 1means RLC/MAC control block format.

4.1.1.7. BS_CV_MAX


This parameter is the binary representation of the parameter BS_CV_MAX, which is used by an MS to calculate the Countdown Value (CV). This parameter consists of four binary codes, and ranges from 0 to 15.

After setting the Countdown Value (CV) in uplink RLC data blocks, an MS notifies the network of BSN of RLC data block to be transferred in the uplink TBF. The CV is calculated in the following formula:

=

=

.,1 5,__,

,t h e n

.1i n t e g e r L e t

o t h e r w i s eM A XC VB Sxi fx

C V

KN T SNB ST B Cr o u n dx

Where,

TBC stands for total RLC data blocks to be transferred in TBF.

BSN' stands for the absolute sequence number of the RLC data blocks. It



ranges from 0 to (TBC - 1).

NTS stands for the number of timeslots assigned to uplink TBF. It ranges from 1 to 8.

Values of K: When the MCS is MCS-7, MCS-8, or MCS-9, the value is 2. For other cases, the value is 1.

The value of round () is the smallest integer in the brace bracket.

BS_CV_MAX is broadcast through system information (SI).

The result of the division is not an integer. When TBC - BSN' 1 = 0, the result is 0.


At the point in time the mobile station transmits the first RLC data block indicating a value of CV other than 15, the mobile station shall transmit afterwards exactly (TBC - BSN' - 1) untransmitted RLC data blocks. If the mobile station receives a change in the Channel Coding Command in a PACKET UPLINK ACK/NACK message during the countdown procedure, the mobile station shall act upon the new Channel Coding Command. The mobile station shall then recalculate the CV values for any untransmitted RLC data blocks using the new RLC data block size. If the mobile station successfully completes the contention resolution procedure during one phase access and the countdown procedure is already running, the mobile station shall recalculate the CV values for any untransmitted RLC data blocks. Any data that arrive from the higher layer after the commencement of the countdown process shall be sent within a future TBF.

The MS can retransmit the RLC data blocks to respond to the Packet Ack/Nack message during the countdown. If the MS retransfers the RLC data blocks, it uses the same CV used for transmitting RLC data blocks earily..

During the countdown second, an MS can send a RLC/MAC control block to respond to a query request. For fixed assignment, when the MS counts 0, it releases the current uplink resources. If receiving a new assignment message during the countdown second, the MS uses a new assignment order when the countdown process ends. The network provides uplink resources for MS to retransmit the RLC data blocks, without sending an Uplink resource Request message.

4.1.1.8. PAN_DEC


The parameter sets a value of parameter Pan_Dec used by counter N3102 of an MS. When the T3182 of the MS expires, the N3102 reduces Pan_Dec value. The



value is represented by 3bit, and ranges from 0 to 7.

When the network judges the radio link failure, the Pan_Dec parameter and N3102 at MS side are used at the same time. When the MS detects the transmit window stall (V(S) = V(A) + WS), it must start T3182.

V (S) < V (A) + WS occurs after an MS receives a Packet Uplink Ack/Nack" message. At this time, the MS stops T3182.

When the T3182 expires, the MS subtracts PAN_DEC from the counter N3102 and perform an abnormal release of TBF with access retry.

When MS receives a Packet Ack/Nack message and allows the increase of V (S) or V (A), the value PAN_INC is added to the counter N3102, but N3102 cannot exceed the PAN_MAX value.

When N3102 0, the MS performs an abnormal release of TBF, and triggers cell reselection.

If PAN_DEC, PAN_INC, and PAN_MAX are set to 0, the counter N3102 is disabled.

Note:

V (S) stands for send state variable, and V (A) stands for acknowledge state variable.

In a GPRS network, the value for Window Size (WS) is 64. In an EGPRS network, the maximum values of WS vary according to different timeslots assigned by the network, and they are greater than 64. For details, see Protocol 04.60 V8.5.0 Chapter 9.1.9..

An MS operating with a fixed allocation must start or restart timer T3184 upon receiving a Packet Uplink Ack/Nack message. If timer T3184 expires, the MS must perform an abnormal release with access retry.


Increasing the value of PAN_MAX and PAN_INC and decreasing the value of PAN_DEC reduce the possibility of TBF abnormal release with cell reselection when the MS cannot receive Packet Uplink Ack messages. However, the MS seizes radio resources for a long time when failing to transmit the data and stopping on the transmit window. Thus, the resource utilization rate is low.

Decreasing the value of PAN_MAX value and PAN_INC value and increasing the PAN_DEC value adds the possibility of TBF abnormal release with cell reselection, and the normal release rate of the TBF decreases. Thus, data transmission rate is affected.



4.1.1.9. PAN_INC


This parameter defines the increment step for counter N3102 of an MS. When the MS receives a Packet Ack/Nack message and allows the increase of V(S) or V (A), PAN_INC is added to counter N3102, but the N3102 value cannot exceed the PAN_MAX value.


For details, see IISetting and Effect.

4.1.1.10. PAN_MAX


This parameter defines the maximum value allowed for counter N3102 of an MS. It is represented by 3bit, and 000, 001111 indicate 4, 832 respectively.


For details, see IISetting and Effect

GPRS cell option parameters:

4.1.1.11. T3193 (Network Side Timer)


T3193 controls the time for TBF release after BSS receives the final data block.

After the network receives a Packet Downlink Ack/Nack message (FAI = 1) or a Packet Control Acknowledgement message, T3193 starts.

If the network receives the last Packet Downlink Ack/Nack message or a Packet Control Acknowledgement message during the operation, the T3193 restarts.

When the network establishes a new downlink TBF for the MS, T3193 stops.

If the T3193 expires, the network releases TBF and the related TFI resources.


T3193 corresponds to T3192 at the MS side, and the setting and effect are the same, be sure that the time length must longer than that of the T3192.



4..1.2. GPRS Cell Access Control Parameters

I. PRACH Control Parameters

PRACH Control Parameters provide the information used for controlling an MS to use the PRACH. These parameters are:

ACC_CONTR_CLASS

MAX_RETRANS1MAX_RETRANS4

TX_INT

S

PERSISTENCE_LEVEL1PERSISTENCE_LEVEL4

4.1.2.1. ACC_CONTR_CLASS


This parameter defines that an MS (Access Control Class = N) is allowed or forbidden to access GPRS cells. The coding of this parameter is 16 bitmap, and each 1 bit corresponds to an access control class. For example, if the access control class for an access-allowed cell of an MS is N, the corresponding bit is set to 0; if the MS is forbidden to access GPRS cells, bit 1 is configured. Note that the bit 11 means the emergency calls.


Classes 0 to 9 are common access classes. Each subscriber is allocated for a class randomly, and this class is recorded in the SIM card of the subscriber.

Classes 11 to 15 are special classes, and they are allocated to partial subscribers.

Classes 11 to 15 are allocated as follows:

Class 15--- PLMN staff

Class 14--- Emergency service departments

Class 13-- Public departments (such as water and gas supply departments)

Class 12--Security department

Class 11--PLMN

Note that greater number does not mean higher access priority. Under special cases, network operators can restrict the access of some classes of subscriber to reduce the system load for emergency events.



4.1.2.2. Max_Retrans1Max_Retrans4


This parameter defines the times of radio priority class 14 of MS respectively to retransmit a Packet Channel Access Request. Level 1 is the highest radio priority level.

This parameter is coded according to the following table.

bit2 10 0 once at mose0 1 twice at most1 0 four times at most1 1 seven times at most


Network operators can set the maximum times an MS to retransmit a Packet Channel Access Request. The greater the Max_Retrans is, the higher the success rate of the packet random access corresponding to radio priority services.

In cells with heavy traffic, a larger Max_Retrans can cause overload and congestion of radio channels. Thus, the success rate of packet access and the radio utilization decrease. Whereas, a smaller Max_Retrans reduces the success rate of packet access..

Under actual conditions, high radio priority services must be guaranteed.. A larger Max_Retrans is configured for high radio priority services, and a smaller Max_Retrans is configured for low radio priority services. Meanwhile, a smaller Max_Retrans is configured for cells with heavy traffic, and a larger Max_Retrans is configured for cells with small traffic.

4.1.2.3. TX_INT and S


The parameter S calculates the minimum timeslot interval between two continuous Packet Channel Access Request messages. The parameter TX_INT indicates the number of extended transmission timeslot of random access. The two parameters decide the timeslot interval of two continuous Packet Channel Access Request messages.

I lists the timeslot interval of two continuous Packet Channel Access Request messages. It is a random value in from {S, S+1S+TxInt1}, and I lists the



relationship between TX_INT and S.

Table 1.1 Timeslot intervals of two continuous Packet Channel Access Request messages

TX_INT coding Corresponding Timeslots

TX_INT coding Corresponding timeslots

0000 3 1000 11

0001 4 1001 12

0010 5 1010 14

0011 6 1011 16

0100 7 1100 20

0101 8 1101 25

0110 9 1110 32

0111 10 1111 50

Table 1.2 Relationship between TX_INT and S

Tx-integer S

An MS uses both CCCH and SDCCH

An MS uses either CCCH or SDCCH

3, 8, 14, 50 55 41

4, 9, 16 76 52

5, 10, 20 109 58

6, 11, 25 163 86

7, 12, 32 217 115

Note:

When an MS sends the Packet Channel Access Request messages for the first time, the timeslot interval is a random value from {0, 1MAX (T, 8) 1}.

The timeslot interval of any two continuous Packet Channel Access Request messages (the timeslot for sending messages is excluded) is a random value from {S, S + 1S + T1}.


The greater the value of parameter T is, the longer the timeslot interval between two continuous Packet Channel Access Request messages. Thus, the chances for the collision of the two messages are smaller on RACH.



The greater the value for parameter S is, the longer the timeslot interval between two Packet Channel Access Request messages. Thus, the chances for the collision of the two messages are smaller on RACH and the utilization of the AGCH and SDCCH is higher. But the MS access time takes long. At this time, the access performance of the network decreases.

Generally, select the value for T where the S is as small as possible to shorten an MS access time, but no overload is present on AGCH and SDCCH.

4.1.2.4. PERSISTENCE_LEVEL1PERSISTENCE_LEVEL4


This parameter defines the P (i) value of an MS whose radio priority is 1. PL2 defines the P (i) value of an MS whose radio priority is 2, and so on.

Radio priority 1 corresponds to the highest priority. When an MS sends a Packet Channel Request message, it defines the R randomly from {0, 1, 215}. If P (i) R, the MS sends the message.


bits4 3 2 10 0 0 0 persistence level 00 0 0 1 persistence level 10 0 1 0 persistence level 20 0 1 1 persistence level 30 1.0.0 persistence level 4: : :1 1 1 0 persistence level 141 1 1 1 persistence level 16


You can set different persistence access levels for different radio priorities.

If P (i) = 0, it is smaller than any R value, that is, all thePacket Channel Access Requests are allowed.

If P (i) = 16 (the maximum value), it is always greater than R value, that is, all the Packet Access Requests are forbidden.

If P (i) = 1, 2, 315, the network rejects partial Packet Channel Access Requests. The greater the P (i) is, the more the Packet Channel Access Requests are rejected.

Setting different persistence access levels for different radio priorities can restrict partial packet access services. Thus, the chances for the collision of random access are small and different services can obtain the required services.



PCCCH ParametersPCCCH parameters control the organization of the PCCCHs in a cell. It includes:

BSPAGBlksRes

BSPRACHBlks

4.1.2.5. BSPBCCHBlks

This parameter defines the number of blocks allocated for the PBCCH in the PCCCH multiframe.

4.1.2.6. BSPAGBlksRes

This parameter sets the number of blocks on each PDCH carrying the PCCCH per multiframe where neither PPCH nor PBCCH should appear. If the multiframes in a block are 51-multiframe, the block is reserved to PAGCH. If the multiframes in a block are 52-multiframe, the block is reserved to PAGCH, PDTCH, and PACCH.

4.1.2.7. BSPRACHBlks

This parameter controls the number of blocks reserved for PRACH on PDCH carrying PCCCH.



Attributes of a serving cellAttributes of a service cell includes:

CELL_BAR_ACCESS_2

EXC_ACC

GPRS_RxLev_Access_Min

GPRS_Ms_TxPwr_Max_CCH

GPRS_Priority_Class

HCS_THR

4.1.2.8. CELL_BAR_ACCESS_2


This parameter combines the CELL_BAR_ACCESS and CELL_BAR_QUALIFY parameters and indicates the status of cell reselection. Permit means that the cell reselection status is normal. NoPermit means that the cell reselection status is barred.


The values of CBA2 and CBQ2 affect the priority of cell selection and reselection. For details, see II and II.

Table 1.3 Effect of CBA2 value and CBQ2 value on cell reselection and priority

CELL_BAR QUALIFY_2

CELL_BAR ACCESS_2

Cell selection priority Cell reselection status

00 0 normal normal00 1 barred barred10 X normal normal11 X low normal

Note:If CBQ2 is set to 10 or 11, the value of CBA2 is unnecessary.



Table 1.4 Priority of cell and reselection decided by CBQ2, CBQ, and CBA

CBQ2 CBQ CBA Cell selection priority

Cell reselection status

00 0 0 normal normal00 0 1 barred barred00 1 0 low normal (note

1)00 1 1 low normal (note

2)10 X X normal normal (note

2)11 X X low normal (note

2) Note:If the CBQ2 is set to 10 or 11, the value of CBA2 is unnecessary.

If the following requirements are met, the cell selection priority and cell reselection status are set to normal.

The cell is in the HPLMN of an MS.

The MS in the cell works in a test and operation mode.

The CBA value is 1.

The CBQ value is 0.

The CBQ2 value is 00.

The access control class 15 is barred.

Note:

1) When the cells with common priority contain no suitable cells, the cells with low priority can be selected.

2) Operators sets a low priority for a cell in the case of Phase 2 MS, but can still decide that the Phase 1 MS camps on this cell.

3) CELL_BAR_QUALIFY_2 means that a cell does not support voice. For MSs of R99 earlier, when the CBA and CBQ are set to 1 and 0 respectively, the cells are barred. MSs before R99 are barred in the cell.

4.1.2.9. EXC_ACC


EXC_ACC is used by the network to prevent MS without exclusive access rights from camping on the cell. This parameter is represented by 1Bit.

Exclusive (namely, 1) means that a cell is used for the Support of Localized Service Area (SoLSA) exclusive access, and Nonexclusive (namely, 0) means that a cell is not used for SoLSA exclusive access.




This parameter is sent in SI3, SI3bis, packet cell update order, or packet measurement order.

Note:

Support of Localized Service Area (SoLSA) is the local serving cell consisting of a cell or a series of cells. The cells can be no-seamless coverage.

The LSA parameter information element (IE) is used for cell reelection of SoLSA MS. This IE contains a series of LSA_ID(s) corresponding to the item Add Frequency list structure in the next list of SI. The SI includes packet cell update order, packet measurement order, or the BA-GPRS used in SI3 or SI3bis.The LAS parameter IE can be null.

If there are too few items in the LSA parameter IE, empty items must be added at the end. If there are too many items in the LSA parameter IE, the last item must be omitted.

4.1.2.10. GPRS_RxLev_Access_Min

This parameter defines the minimum receiving level required in the cell when an MS accesses the system. The MS calculates C1 value through the parameter.

4.1.2.11. GPRS_Ms_TxPwr_Max_CCH

This parameter defines the maximum transmit power level when an MS accesses the packet control channel.

4.1.2.12. GPRS_Priority_Class

This parameter defines the class of hierarchical cell structure (HCS) of a GPRS cell.

4.1.2.13. HCS_THR


This parameter defines the Hierarchical Cell Structure (HCS) signal strength threshold, and judges the signal level threshold of HCS.




bit5 4 3 2 1

0 0 0 0 0 -110 dBm

0 0 0 0 1 -108 dBm

1 1 1 1 1 -48 dBm


C31 and C32 are new algorithms for GSM cell reselection, and they are used only when PBCCH is present in the system.

C31 uses signal strength decision rule. This rule is called as level threshold decision rule of HCS, and decides the cell reselection priority for hierarchical GPRS and LSA.

The C31 is defined as follows:

In serving cells, C31 (s) = RLA_P (s) - HCS_THR (s).

In neighbor cells, C31 (n) = RLA_P (n) - HCS_THR (n) TO (n) * L (n).

Where,

RLA_P indicates the receiving signal level, TO indicates the temporary offset, and L is related to the priority class.

If the PRIORITY_CLASSS (serving cell) is the same with PRIORITY_CLASSS (neighbor cell), L is 0.

If PRIORITY_CLASSS (serving cell) is not the same with PRIORITY_CLASSS (neighbor cell), L is 1.

PSI1-related AttributesThe PSI1-related attributes include following parameters:

PSI1_Repeat_Period

EXT_Measurement_Order

PSIStatusInd



4.1.2.14. PSI1_Repeat_Period

I. Dedinition and Format

This parameter calculates TC value. The value sets the frames and blocks for sending PSI on PBCCH.


bit4 3 2 1

0 0 0 0 PSI1 repeated period = 1 multiframe

0 0 0 1 PSI1 repeated period = 2 multiframes

1 1 1 1 PSI1 repeat period = 16 multiframes

This parameter can be sent through the SI13 on BCCH, PSI1 on PBCCH, or PSI3 or PSI3bis of neighbor cells received by serving cell.


If the BCCH is present, TC value is (FN DIV 51) mod (8)). Different types of messages are sent at corresponding occasions based on TC values.

If the BCCH is present, TV value is calculated as in the following formula:

TC = (FN DIV 52) mod PSI1_REPEAT_PERIOD

When TC value is 0, PSI1 IS sent according to the rules in 1 and 2. Other PSI is divided into two groups. One group is sent at a lower repeated rate. The other group is sent at a higher repeated rate.

The later group is indicated by the parameter PSI_COUNT_HR in PSI1, and the values of this parameter range from 0 to 16. The SI in this group is sent according to rule 3.

The former group is indicated by the parameter PSI_COUNT_LR in PSI1, and the values of this parameter range from 0 to 16. The SI in this group is sent according ot rule 4.

The rules for sending PSI are as follows:

1) When TC is 0, PSI1 is sent on block B0. 2) If the value of BS_PBCCH_BLKS is greater than 1, the PSI1 must be sent

on block B6 when TC is 0.3) The PSI in the group with high repetition rate is sent in the order of

occurrence sequence when TC is 0 using the PBCCH blocks within each multiframe. The sending must not occupy the rules in 1 and 2. The PSI sequence is repeated when TC is 0.

4) The PSI messages in the group with low repetition rate are sent



continuously in the order of occurrence sequence using the PBCCH blocks within each multiframe. The sending must not occupy the rules in 1 and 2. The PSI sequence is repeated when FN is 0.

If a special type of PSI is divided into several parts, they are sent in the same PSI group according to rules 3 or 4. The PSI parts are sent in an ascending order of PSI number.

The same PSI cannot be repeated in the list decided by PSI_COUNT_LR and PSI_COUNT_HR.

The whole PSI consists of:

The part specified by PSI_COUNT_LR The part specified by PSI_COUNT_HR PSI1

Note:

The network must use the parameter BS_PBCCH_BLKS and PSI1_REPEAT_PERIOD and the PSI of a cell can be sent according to the rules from 1 to 4.

The network must optimize PSI broadcast so that an MS obtains the parameters for cell reselection and access without the consideration of power consumption only.

An MS can estimate the minimum time for cell reselection using a PSI mapping solution.

4.1.2.15. EXT_Measurement_Order

This parameter indicates how an MS sends the measurement report. If the value is NO, the MS performs the cell reselection does not send a measurement report to the network.

If the value is YES, the MS must send a measurement report during cell reselection for extended measurement (EM) of network.

Note:

EM0, means that the MS does not perform the EM.

EM1 means that the MS must send an EM report to network.

4.1.2.16. PSIStatusInd


PSI Status Indication (PSIStatusInd) determines whether the network supports PACKET PSI STATUS message. This parameter is configured as "NO by default.



II. Setting and Format

This parameter is optional, and an MS also can require system information. If the network supports the PACKET PSI STATUS message, an MS obtains PBCCH information while sending a PACKET PSI STATUS message to network.

PACKET PSI STATUS message indicates the status of PSI saved in the MS. The MS must contain more PSI as possible meeting the PSI list structure in the received PACKET PSI STATUS messages. The following rules must be followed:

The PSI type must be related to MS-supported characteristics, such as non-GSM capability and multi-RAT ability.

The network must specify the type of optional PSI on PBCCH.

The PSI type values are included in the PSI list of the PSI STATUS messages. The network decides PSI types that an MS can receive and the status of PSI saved in the MS by using this message.

When obtaining part of PSI messages, an MS must obtain PAI change marks of PAI message types. . At this time, the MS points out the current status of the PSI type in the PACKET PSI STATUS message, except that when the PSI index is 0, that is, the status of the PSI type pointed out by the MS is different from that of the PACKET PSI STATUS message received by the MS.

When the MS works in packet transmission mode, a PACKET PSI STATUS message is sent on PACCH. When the MS obtains the PBCCH information, the PACKET PSI STATUS message is sent first at a proper time after the process starts.

When the MS obtains PBCCH information,, the PACKET PSI STATUS message can be sent to the network for four times at most, with the interval of one second.

When the MS suspends the TBF to receive the required PSI on PBCCH, the PACKET PSI STATUS message cannot be sent. When the MS has obtained the whole PSI on PBCCH, the MS does not need to send the PACKET PSI STATUS message.

4..1.3. Power Control Parameters

An MS uses power control parameters to define transmit power level. Power control parameters are:

ALPHA

T_AVG_W

TAVG_T



Pb

PC_MEAS_CHAN

INT_MEAS_CHANNEL_LIST

NAVG_I

4.1.3.1. ALPHA


This parameter calculates the PCH value of MS output power on each PDCH.

This parameter defines the reduced MS TX levels corresponding to path loss when the MS GPRS dynamic power control is used. An MS uses this parameter to calculate the PCH uplink PDCH output power. For open loop power control, the coding 1.0 is used.


bit4 3 2 1

0 0 0 0 = 0.0

0 0 0 1 = 0.1

0 0 1 0 = 0.2

: :

1 0 0 1 = 0.9

1 0 1 0 = 1.0


The PCH value for MS frequency output power on each PDCH is calculated as follows:

PCH = min ( 0 - CH - * (C + 48), PMAX)

Where:

CH indicates power control parameter defined by channels. This parameter is sent to an MS thorugh RLC control messages.

0 indicates that for GSM400, GSM900, and GSM850, 39dBm is used.

indicates the system parameter. It can be broadcast on PBCCH and sent through RLC control messages.

C indicates the unified incoming level of an MS.

PMAX indicates the maximum output power of a cell. When PBCCH or CPBCCH exists, the PMAX is GPRS_MS_TXPWR_MAX_CCH; otherwise,



the PMAX is MS_TXPWR_MAX_CCH.

The previous values are represented by dBm.

When an MS receives new values of CH and , the MS updates the PCH value two radio time blocks after receiving the final timeslot of the message block that contains a new PCH value. The two radio time blocks provide the time for timeslot reallocation.

Though higher precision is provided, an MS rounds the values of output power to the nearest value. The actual transmit output power meets the actual precision required by GSM protocols. In addition, when the transmit output power increases or decreases by 2dB, the corresponding transmit output power increases or decreases by 1.5dB.

In a radio block, the output power of four bursts must be consistent with each other.

Before PRACH or RACH accesses a cell and receiving the first power control parameter on PDCH in packet transfer phase, the MS uses the defined PMAX output power to send messages.

MS_TXPWR_MAX_CCH is broadcast on BCCHs of a cell. For the three categories of 1800 MHz MSs, the values of POWER OFFSET must be added to BCCH.

GPRS_MS_TXPWR_MAX_CCH is broadcast on PBCCHs and CPBCCHs of a cell.

If receiving the GPRS_MS_TXPWR_MAX_CCH on PBCCHs before the PRACH accesses a cell, the MS uses MS_TXPWR_MAX_CCH to replace the PMAX.

If an MS does not support the output power value from the formula, the MS uses the nearest value to support power transfer.

4.1.3.2. T_AVG_W


This parameter sets the signal strength filter period for power control in packet idle mode. An MS uses this parameter to measure the downlink signal strength in packet idle mode and calculate C value. Here C stands for the level of MS to receive signals,

This parameter is represented by 5Bit. The value is 2(k/2) / 6 multiframes, among which the value of K ranges from 0 to 25. When the values of K are greater than 25, the MS interprets the value as 25.


In packet idle mode, the MS periodically measure the received signal level of the



PCCCH, BCCH, CPCCCH, CBCCH, CFCCH, or CSCH. The MS measures the received signal level of each paging block monitored by the MS according to its current DRX mode and its paging group.

Following formula calculates the normalized C value for each radio block:

Cblock n = SSblock n + Pb

Where:

SSblock,n indicates the received signal level of the four normal bursts that compose the block.

Pb indicates the BTS output power reduction (relative to the output power used on BCCH) used on the channel on which the measurements are performed. For PCCCH, Pb is broadcast on PBCCH. If frequency hopping is being used on the associated physical channel, Pb is reduced by 25% for each burst in the block which is received on the BCCH frequency. For BCCH and for COMPACT, Pb is 0 (not broadcast).

Finally, the Cblock,n values are filtered with a running average filter:

Cn = (1-a) Cn-1 + a Cblock nWhere,

a is the forgetting factor: a = 1/MIN (n, MAX (5, TAVG_W*NDRX)).

When a" is near to 1, Cblock n functions rather than Cn-1. When "a is near to 0, Cn-1 functions.

NDRX indicates the average number of monitored blocks per multiframe according to its current DRX mode and its paging group

4.1.3.3. TAVG_T


This parameter sets the signal strength filter period for power control in packet transfer mode. An MS uses this parameter to measure the downlink signal strength in packet transfer mode and calculate C value.

This parameter is represented by 5Bit. The value is 2(k/2) / 6 multiframes, among which the value of K ranges from 0 to 25. When the values of K are greater than 25, the MS interprets the value as 25.

II. Seting and Effect

In packet transfer mode, the MS uses the same received signal level measurements as made for cell reselection on the BCCH carrier of the serving cell or, for COMPACT, on the CPBCCH carrier of the serving cell. The measurements are filtered with a running average filter:

Cn = (1-b) Cn-1 + b SS n,



Where:

SSn is the received signal level of the measurement samples.

b is the forgetting factor. b=1/(6* TAVG_T).

n is the iteration index. When entering packet transfer mode, the filter continues using the values of n and C obtained in packet idle mode.

If the parameter indicates to use one PDCH, the MS replaces the received signal level measurement of each radio block on the PDCH monitored by the MS for PACCH.

If the downlink power control closes, the PC_MEAS_CHAN indicates measurements on the BCCH or CPBCCH, or the MS is not required to meet 05.05 requirements.

The MS can discard new PC_MEAS_CHAN values received in packet transfer mode. For each downlink radio block Cblock,n, if PBCCH does not exist, and for COMPACT, the value of Pb is 0, Cblock n = SSblock n + Pb. Finally, the Cblock,n values are filtered with a running average filter:

Cn = (1-c) Cn-1 + c Cblock n

Where:

c is the forgetting factor. C = 1/(12* TAVG_T).

n is the iteration index. When entering packet transfer mode, the filter continues using the values of n and Cn obtained in packet idle mode.

Note that this method is suitable in the case where BCCH or CPBCCH is in another frequency band than the used PDCHs.

Each time a new Cn value is obtained or whenever the MS uses new CH or values, the current Cn value is used to update formula PCH = min( 0 - CH - * (C + 48), PMAX).

For each received block on PDCHs monitored by the MS, the MS calculates the variance of the received signal level using the following formula:

BL_VARn = 1/ (j-1)*SUM (SSk - SSblock n) 2, k = 1...4

Where:

SSk is the received signal level of burst k within the block.

SSblock,n is the average received signal level of the j normal bursts that compose the radio block

j is the number of bursts in the radio block. The maximum value is 4.

If frequency hopping is used and 1 burst of the block is received on the BCCH carrier, the burst is discarded from the calculation, namely, j = 3. If 2 bursts are received on the BCCH carrier, the whole block shall be discarded. If 3 bursts are



received on the BCCH carrier, the other burst shall be discarded, namely, j = 3.

If more than one PDCH are monitored, the MS tries to find one correctly received block for the BL_VAR calculation in each block period. The block is from any of the monitored PDCHs.

The reported value of SIGN_VAR is the average BL_VAR value within the reporting period. The first reporting period starts with the first assignment message of an uplink or downlink transfer. The reporting period ends no earlier than two blocks before the transmission of a quality report and no later than one block before the transmission of a quality report. Averagely, measurements made during previous reporting periods always are discarded.

SIGN_VAR is in the channel quality report. If the channel quality report is included in a PACKET RESOURCE REQUEST message, which is retransmitted due to lack of response, the same SIGN_VAR value is repeated and no new reporting period is started. This will ensure that a valid SIGN_VAR value exists

An MS performing an uplink transfer using half duplex mode is not required to measure received signal level. The MS updates PCH only when it receives new CH values. In this case, the MS uses the last Cn value measured before the uplink transfer

TAVG_T and PC_MEAS_CHAN are broadcast on PBCCH. If PBCCH does not exist, they are broadcasted on BCCH or on CPBCCH.

4.1.3.4. Pb


This parameter defines the power reduction value used by the BTS on PBCCH blocks. And the value is relative to the output power used on BCCH.

This parameter is coded in the following table.

bit4 3 2 1

0 0 0 0 Pb = 0 Db

0 0 0 1 Pb = -2 dB

0 0 1 0 Pb = -4 dB

: :

1 1 1 1 Pb = -30 dB


Following formula calculates the C value for each radio block:



Cblock n = SSblock n + Pb

Where:

SSblock,n is the average received signal level of the four normal bursts that compose the block.

Pb is the BTS output power reduction (relative to the output power used on BCCH) used on the channel where the measurements are performed. For PCCCH, Pb is broadcasted on PBCCH. If frequency hopping is used, Pb is reduced by 25% for each burst in the block which is received on the BCCH frequency. For BCCH and COMPACT, if Pb is 0, it is not broadcasted.

4.1.3.5. PC_MEAS_CHAN


This parameter sets where the MS shall measures the received power level on the downlink for the purpose of the uplink power control.

If the value of the parameter is 0, it indicates that the downlink measurements for power control are made on BCCH. If the value of the parameter is 1, it indicates that downlink measurements for power control are made on PDCH.

4.1.3.6. INT_MEAS_CHANNEL_LIST

This parameter identifies a cell broadcasts INT_Meas_Channel_List messages through PSI4. If yes, the PSI4 contains the channel list for interference measurements.

If the value of the parameter is 0, it means that PSI4 does not broadcast INT_Meas_Channel_List messages. If the value of the parameter is 1, it means that PSI4 broadcasts INT_Meas_Channel_List messages.

4.1.3.7. NAVG_I


This parameter sets the interference signal strength filter for power control. The value is 2(k/2), among which the K value ranges from 0 to 15.


1) Packet transfer mode

In packet transfer mode, the MS measures the interference signal level on the same carrier as the assigned PDCHs. The MS measures the interference signal levels during the search frames and PTCCH frames, which are not required for BSIC decoding or the timing advance measurements.

The MS shall measure as many channels (timeslots) as possible. The minimum timeslots are no less than the assigned timeslots for the MS to receive.



For each channel, every measurement SSCH,n consists of at least two signal level samples from one search frame and one PTCCH frame. Thus, the SACCH frames are avoided (except for a physical channel with two TCH/Hs) and only the interference is measured.

Following running average filter averages the measured interference.

CH,n = (1-d) CH,n-1 + d SSCH,n, CH, 0 = 0

Where,

d is 1/MIN(n, NAVG_I).

n is the iteration index.

The filter is restarted with n=1 for the first sample every time a new cell is selected.

If the measurements on a channel is interrupted due to a change of packet mode that is, the packet mode changes from transfer mode to idle mode, the last obtained n and CH,n values are saved.

When reentering packet transfer mode, the filter continues using the values obtained during packet idle mode, because these channels are measured in both modes.

If frequency hopping is used, channels only differing in MAIO are considered the same. For other channels, if the measurements are resumed within NAVG_I/2 multiframes, the filter continues the calculation using the saved values. Otherwise the filter is restarted.

Channel reassignment during packet transfer mode is considered as a start of a new packet transfer mode preceded by a zero length packet idle mode.

For each channel, the MS performs at least NAVG_I (rounded to the nearest integer) measurements of SSCH,n before valid CH values can be determined

During GPRS downlink TBF transfer, the MS measures the received signal quality. The reported RXQUAL is the average within the reporting period and only successfully decoded blocks intended for the MS are included in the average processing period.

After the reporting period ends, the subsequent reporting starts no earlier than two blocks before the transmission of a quality report. Averagely, measurements made during previous reporting periods are discarded.

The MS must transfer 8 CH values and the RXQUAL, C and SIGN_VAR values to the network in the Channel Quality Report (CQR) sent on PACCH.

NAVG_I is broadcasted on PBCCH. If PBCCH does not exist, NAVG_I is broadcasted on BCCH.

2) Packet idle mode



In packet idle mode, the MS measures the interference signal level on the channels indicated by the parameter INT_MEAS_CHANNEL_LIST. When PBCCH does not exist, the parameter INT_MEAS_CHANNEL_LIST is optionally broadcasted on PBCCH or CPBCCH.

The measurements for interference signal level is related to its multi-timeslot ability. If the parameter INT_MEAS_CHANNEL_LIST does not exist and the MS does not measure the interference signal level for cell reselection controlled by the network, the MS is not required to perform interference measurements.

These measurements must be made in the search frames and the PTCCH frames. During each paging period, if such frames are available and not required for BSIC decoding, the MS must make at least one measurement on each carriers.

The filter must be restarted with n=1 for the first sample every time a new cell is selected. If the measurements on a channel are interrupted due to a change of packet mode, the last obtained n and CH,n values are saved.

When entering packet idle mode, the filter continues using values obtained during packet transfer mode, because these channels are measured in both modes.

If frequency hopping is used, channels only differing in MAIO shall be considered the same. For the other channels, if the measurements are resumed for the same channel within KC*NAVG_I/4 multiframes or KC*NAVG_I/2 paging periods, whichever is greater, the filter continues the calculation using the saved values. Otherwise the filter must be restarted. KC is the number of carriers in the INT_MEAS_CHANNEL_LIST.

For each channel, the MS must perform at least NAVG_I (rounded to the nearest integer) measurements of SSCH,n before valid CH values can be determined.

NAVG_I is broadcasted on PBCCH. If PBCCH does not exist, NAVG_I is broadcasted on BCCH.

4..1.4. GPRS Cell Identity

The GPRS cell-related parameters define the attributes of the cells, such as the attributes of routing areas (RA) and access priority classes. These parameters are:

RAC

BSIC

SPLT_PG_CYCYLE

PRIORITY_ACCESS_THR

RAColor



4.1.4.1. RAC

Routing Area Code (RAC) identifies a routing area. The network plans the codes of the RA.

4.1.4.2. BSIC

The configuration of BSIC must be consistent with that of the BSC.

4.1.4.3. SPLT_PG_CYCYLE

This parameter identifies that a cell supports SPLT_PG_CYCYLE on CCCH.

4.1.4.4. PRIORITY_ACCESS_THR

This parameter sets the value of PRIORITY_ACCESS_THR for a GPRS cell. And the value set an MS access is allowed for priority level 1 to 4.

4.1.4.5. RAColor

This parameter sets the RAColor for a GPRS cell.

4..1.5. GPRS Cell Reselection Parameters

GPRS cell reselectionGPRS cell reselection parameters are:

GPRS_CELL_RESELECT_HYSTERESIS

RA_RESELECT_HYSTERESIS

C31_HYST

C32_QUAL

GPRS_TEMPORARY_OFFSET

GPRS_PENALTY_TIME

GPRS_RESELECT_OFFSET

RANDOM_ACCESS_RETRY

T_RESEL

4.1.5.1. GPRS_CELL_RESELECT_HYSTERESIS


This parameter sets the additional hysteresis which applies in ready state for cell reselection in the same RA. If the parameter is in standby state, the default value is GPRS_CELL_RESELECT_HYSTERESIS.



This parameter is encoded according to the following table.

Bit3 2 1

0 0 0 0 dB

0 0 1 2 dB

0 1 0 4 dB

0 1 1 6 dB

1 0 0 8 dB

1 0 1 10 dB

1 1 0 12 dB

1 1 1 14 dB


In packet idle mode, GPRS cell reselection is the GSM cell reselection.

In standby or ready state, when evaluating the best cell, the following hysteresis values mustl be subtracted from the C32 value for the neighbor cells:

In standby state, if the new cell and the serving cell are in the same RA, the hysteresis value is 0.

In ready state, if the new cell and the serving cell are in the same RA, and the parameter C31_HYST is set, GPRS_CELL_RESELECT_HYSTERESIS must be subtracted from the C31 value for the neighbor cells.

In standby or ready state, if the new cell and the serving cell are in a different routing area, RA_RESELECT_HYSTERESIS must be subtracted from C32 value.

In case of a cell re-selection occurred within the previous 15 seconds, 5 dB must be subtracted from C32 value.

GPRS_CELL_RESELECT_HYSTERESIS, C31_HYST and RA_RESELECT_HYSTERESIS are broadcasted on PBCCH of the serving cell.

This parameter prevents frequent cell update caused by frequent cell reselection in ready state. Thus the traffic flow is increased.

If the value of this parameter is too small, cell update occurs frequently. If the value of this parameter is too great, cell update cannot be initiated in time. In this case, the MS may not in the best cell and the carrier-to-interference ratio (CIR) of the received signal is low. Thus the transmit rate is affected. Generally, the value is set to 46dB.



4.1.5.2. RA_RESELECT_HYSTERESIS


This parameter indicates in both standby and ready state the additional hysteresis which applies when an MS selects a cell in a new Routing Area.


Bit3 2 1

0 0 0 0 dB

0 0 1 2 dB

0 1 0 4 dB

0 1 1 6 dB

1 0 0 8 dB

1 0 1 10 dB

1 1 0 12 dB

1 1 1 14 dB


In standby or ready state, if the new cell and the serving cell are in a different routing area, RA_RESELECT_HYSTERESIS must be subtracted from C32 value. This parameter replaces the parameter GPRS_ CELL_RESELECT_HYSTERESIS if they are in the same RA. Generally, the value of hysteresis in RA reselection is greater than that of the hysteresis in GPRS cell reselection.

4.1.5.3. C31_HYST


This parameter sets that the GPRS_CELL _RESELECT_HYSTERESIS is applied to the C31 criterion.

If the value is set to 1, the GPRS_CELL _RESELECT_HYSTERESIS is applied to the C31 criterion.

If the value is set to 0, the GPRS_CELL _RESELECT_HYSTERESIS is not applied in the C31 criterion.


The signal level threshold criterion parameter C31 for hierarchical cell structures (HCS) is used to determine whether to use the prioritized hierarchical GPRS and



LSA cell re-selection. If more than one cell has the highest priority level, the MS selects the cell of the greatest C32 value.

C31 (s) = RLA_P (s) - HCS_THR (s) (serving cell)

C31 (n) = RLA_P (n) - HCS_THR (n) TO (n) * L (n) (neighbor cell)

Where,

HCS_THR is the signal level threshold applied in HCS GPRS and cell reselection. HCS_THR is broadcasted on PBCCH of the serving cell.

4.1.5.4. C32_QUAL


This parameter defines whether to use exception rules for GPRS_RESELECT_OFFSET in cell reselection.

If the value is set to 1, when an MS calculates the C32 value in cell reselection, the parameter GPRS_RESELECT_OFFSET is used.

If the value is set to 0, when an MS calculates the C32 value in cell reselection, the parameter GPRS_RESELECT_OFFSET is not used.

Here C32 defined the criteria for an MS to select a cell among the cells having the same priority.


C32 criterion improves the C2 criterion used by GSM. It applies the offset and hysteresis value to each cell. When cell update programs or cell reselection for the update programs must be executed, the hysteresis value is used. When no PBCCH exists in a serving cell, an MS executes the cell reselection according to C2 criterion.

C32 (s) = C1 (s) (serving cell)

C32 (n) = C1 (n) + GPRS_RESELECT_OFFSET (n) TO (n) * (1-L (n)) (neighbor cell)

Where:

TO (n) = GPRS_TEMPORARY_OFFSET (n) * H (GPRS_PENALTY_TIME (n) - T (n))

L (n) = 0 if PRIORITY_CLASS (n) = PRIORITY_CLASS(s)

L (n) = 1 if PRIORITY_CLASS (n) PRIORITY_CLASS (s)

H (x) = 0 if x < 0

H (x) = 1 if x 0

T is the timer. If the MS records a cell in the 6 neighbor cells of the highest priority, the timer of the cell starts when the initial value is set to 0. If previous cells are added to the neighbor cells of the highest priority, the



value for T is set to PENALTY_TIME.

4.1.5.5. GPRS_TEMPORARY_OFFSET


This parameter indicates the negative offset of a cell that the MS must use for duration of GPRS_PENALTY_TIME.


Bit3 2 10 0 0 0 dB0 0 1 10 dB0 1 0 20 dB0 1 1 30 dB1 0 0 40 dB1 0 1 50 dB1 1 0 60 dB1 1 1 infinity

4.1.5.6. GPRS_PENALTY_TIME

II. Definition and Format

This parameter defines the length of time for which GPRS_TEMPORARY_OFFSET is active.


Bit5 4 3 2 10 0 0 0 0 10 seconds0 0 0 0 1 20 seconds . . . 1 1 1 1 1 320 seconds

H (x) = 0 if X < 0; H (x) = 1 if X > 0.

L = 0 if PRIORITY_CLASS (serving cell) = PRIORITY_CLASS (neighbor cell).

L = 1 if PRIORITY_CLASS (serving cell) PRIORITY_CLASS (neighbor cell).



4.1.5.7. GPRS_RESELECT_OFFSET


This parameter is used by the MS to apply a positive or negative offset and a hysteresis to the GPRS cell reselection criterion.


Bit5 4 3 2 10 0 0 0 0 -52 dB0 0 0 0 1 -48 dB

...0 1 0 1 0 -12 dB0 1 0 1 1 -10 dB

...1 0 1 1 0 +12 dB1 0 1 1 1 +16 dB

...1 1 1 1 1 +48 dB

Note:

Default value of this parameter is 0 dB. If the field is omitted from the message, the default value is 0 dB.

4.1.5.8. RANDOM_ACCESS_RETRY


This parameter defines that the MS is allowed to access another cell. If the value is set to 1, the MS is allowed to access another cell if the cell is available.

II. Settng and Effect

When an MS aborts all TBFs in progress, if the access in another cell is allowed (for example, RANDOM_ACCESS_RETRY = 1), the MS performs an abnormal cell reselection and initiates the establishment of an uplink TBF. The MS does not reselect back to the original cell for T_RESEL seconds if another suitable cell is available. The parameters RANDOM_ACCESS_RETRY and T_RESEL (default value 5 seconds) are broadcast in PSI3.

If the access in another cell is not allowed (for example, the RANDOM_ACCESS_RETRY bit is not set), or no neighbor cell is available, the MS returns the CCCH or PCCCH and sends and reports an RLC/MAC failure to upper layers.



4.1.5.9. T_RESEL


This parameter is time parameter. When an MS performs an abnormal release with cell reselection, if other cells are available, the MS cannot reselect this cell in T_RESEL seconds.

This parameter is coded according to following table.

Bit3 2 10 0 0 5 seconds0 0 1 10 seconds0 1 0 15 seconds0 1 1 20 seconds1 0 0 30 seconds1 0 1 60 seconds1 1 0 120 seconds1 1 1 300 seconds

4..1.6. Measurement Report Control Parameters

The network controls cell reselection process, and orders the MS to send measurement reports and to receive decisions from the network. The network control parameters set the attributes when MS sends network control measurement reports in MM Read state. They are:

NETWORK_CONTROL_ORDER NC_NON_DRX_PERIOD NC_REPORTING_PERIOD_I NC_REPORTING_PERIOD_T

4.1.6.1. NETWORK_CONTROL_ORDER


This parameter decides how the MS sends measurement reports in MM Ready state.




Bit2 10 0 NC0 0 1 NC1 1 0 NC2 1 1 RESET

Note:

This parameter can be set to NC0, NC1, and NC2.


If the NETWORK_CONTROL_ORDER parameter = NC0, the MS controls auto cell reselection, without sending measurement repots to the network.If the NETWORK_CONTROL_ORDER parameter = NC1, the MS controls auto cell resection, and sends measurement reports.If the NETWORK_CONTROL_ORDER parameter = NC2, the MS sends measurement reports to the network, without auto cell reselection. The network controls the cell reselection.

4.1.6.2. NC_Non-DRX_PERIOD


This field indicates the minimum time the mobile station stays in non-DRX mode after an NC-measurement report has been sent.

This parameter is coded according to the following table:

bit3 2 10 0 0 No non-DRX mode after a measurement report has been sent.0 0 1 0.24s 0 1 0 0.48s (default)0 1 1 0.72s 1 0 0 0.96s 1 0 1 1.20s1 1 0 1.44s 1 1 1 1.92s




When an MS works in a non_DRX mode, the MS consumes more power. Therefore, a larger DRX_Timer_Max value shortens the TBF establishment time, but the MS consumes more power. A smaller DRX_Timer_Max value saves the MS power. However, paging process is added to DRX mode, so the signaling load of system and delay of data transmission increases.

4.1.6.3. NC_REPORTING_PERIOD_I and NC_REPORTING_PERIOD_T


These fields indicate the time period for cell reselection measurement reporting for packet idle mode (I) and packet transfer mode (T) respectively when the MS performs NC measurements.

This parameter is coded according to the following table:

bit3 2 10 0 0 0.48s0 0 1 0.96s0 1 0 1.92s0 1 1 3.84s (default value for NC_REPORTING_PERIOD_T) 1 0 0 7.68s1 0 1 15.36s1 1 0 30.72s1 1 1 61.44s (default value for NC_REPORTING_PERIOD_I)


When working in mode NC1 or NC2, the MS performs NC measurements. It determines the period of measurement repot using the parameters (NC_NON_DRX_PERIOD, NC_REPORTING_PARAMETER_I, and NC_REPORTING_PARAMETER_T) in the field (the PSI5, the SI13, PSI13,, the PACKET CELL CHANGE ORDER or the PACKET MEASUREMENT ORDER message). If NC_NON_DRX_PERIOD, NC_REPORTING_PERIOD_I or NC_REPORTING_PERIOD_T are not received by the MS, the default values must be used.

When ordered to send measurement reports, the MS must continuously monitor all carriers in BA (GPRS) or as indicated by the parameter NC_FREQUENCY_LIST and the BCCH carrier of the serving cell. The measurement requirements vary with actual packet mode.

For each carrier, the measured received signal level (RXLEV) must be the



average of the received signal level measurement samples in dBm taken on that carrier within the reporting period. The reporting period is defined as follows:

In packet idle mode, the reporting period is NC_REPORTING_PERIOD_I rounded off to the nearest smaller integer multiple of DRX period if NC_REPORTING PERIOD_I is greater than DRX period, otherwise, the reporting period is DRX period.

In packet transfer mode, the reporting period is indicated in NC_REPORTING_PERIOD_T.

Extended measurement parametersThe network also can request measurement reports from the MS for other purposes than cell re-selection. This is indicated by the parameter EXT_MEASUREMENT_ORDER.

A set of measurement reporting parameters (EXT_MEASUREMENT_ORDER, EXT_FREQUENCY_LIST, EXT_REPORTING_PERIOD, EXT_REPORTING_TYPE, INT_FREQUENCY and NCC_PERMITTED) is broadcast on PBCCH or CPBCCH. The parameters are also sent individually to an MS on PCCCH, CPCCCH or PACCH. At that time, they override the broadcast parameters. The individual parameters are valid until the RESET command is sent to the MS, there is a downlink signaling failure or the MS selects a new cell. The extended measurement parameters are:

EXT_MEASUREMENT_ORDER NCC_PERMITTED INT_FREQUENCY EEXT_REPORTING_TYPE EXT_REPORTING_PERIOD

4.1.6.4. EXT_MEASUREMENT_ORDER


The EXT_MEASUREMENT_ORDER field indicates to the MS how to interpret the rest of the extended measurement parameters.


bit2 10 0 EM0 0 1 EM1 1 0 Reserved1 1 Reset



Note:

This parameter can be set to EMO, EM1, and reset.

If the EXT_MEASUREMENT_ORDER parameter = EM1, the MS does not perform extended measurements. If EXT_MEASUREMENT_ORDER parameter = EM1, the MS must send measurement reports to the network.

4.1.6.5. NCC_PERMITTED

This field is a bitmap of NCCs for which the mobile station is permitted to report measurement. This bitmap relates to NCC part of BSIC (see coding field in the protocol 04.08).

4.1.6.6. INT_FREQUENCY

This optional field indicates the frequency upon which the interference measurement is made. This field is an index into the EXT Frequency List. If the field is not included in any instance of the message, no interference measurements are done. The range is from 0 to 31.

4.1.6.7. EXT_REPORTING_TYPE


This field indicates the type of extended measurement report used on extended measurement frequency.

When ordered to send extended measurement reports, the MS must monitor all carriers as indicated by the parameter EXT_FREQUENCY_LIST. The parameter EXT_REPORTING_TYPE indicates one of three different types of reporting:

Type 1: Carriers that must be reported if they are among the 6 strongest carriers regardless of whether BSIC was decoded or not. The measurement report must contain received signal level and, if successfully decoded BSIC.

Type 2: Carriers that must be reported if they are among the 6 strongest carriers and BSIC is successfully decoded and with allowed NCC part as indicated by NCC_PERMITTED. The measurement report must contain received signal level and BSIC.

Type 3: Carriers that must be reported without BSIC decoding. The measurement report must contain received signal level. In addition interference can be reported for one carrier.

4.1.6.8. EXT_REPORTING_PERIOD


This field indicates the time interval between extended measurement reports. This field is coded according to the following table:.



bit3 2 10 0 0 60s0 0 1 120s0 1 0 240s0 1 1 480s1 0 0 960s1 0 1 1920s (default value for EXT_REPORTING_TYPE ) 1 1 0 3840s1 1 1 7680s

Power control measurement parametersThe power control data sets power control-related parameters, such as the conditions for starting power control. The parameters are:

MinRptNumForGammaCh sets the minimum number of valid measurement reports received by PCU for power algorithm.

IdealRxQual sets the expected ideal receiving quality. The receiving quality corresponds to bit error rate (BER) of channels.

RxQualTolerance sets the tolerance value for power control, and it corresponds to offset value of ideal receiving quality.

GammaChChangeTime sets the time when GammaCh changes and the received quality must meet a condition.

GammaChChangeStep sets the steps every time when GammaCh changes dynamically.

4..1.7. CS Change and Control Parameters

A GPRS system has four coding schemes (CS). They are CS-1, CS-2, CS-3, and CS-4. The higher the CS level is, the higher the data transmission rate is, and the more the requirements for channel quality are. PCU system changes CS dynamically for the best fulfillments according to factors like channel quality. The CS change and control parameters are as follows:

MinMeasRptNumForCsdc sets the minimum number of measurement reports for dynamic change of CS, namely, the averaged number of measurement reports.

UlCsChangeQualThreshold0 sets the threshold reference value of channel quality for judging dynamic change of CS-1 and CS-2 on uplink TBF.

UlCsChangeQualThreshold1 sets the threshold reference value of channel



quality for judging dynamic change of CS-2 and CS-3 on uplink TBF. UlCsChangeQualThreshold2 sets the threshold reference value of channel

quality for dynamic change of CS-3 and CS-4 on uplink TBF. UlUpwardCsdcQualHysteresis0 sets the hysteresis value when the upward

TBF changes from CS-1 to CS-2. UlUpwardCsdcQualHysteresis1 sets the hysteresis value when the upward

TBF changes from CS-2 to CS-3. UlUpwardCsdcQualHysteresis2 sets the hysteresis value when the upward

TBF changes from CS-3 to CS-4. UlDownwardCsdcQualHysteresis0 sets the hysteresis value when the

downward TBF changes from CS-2 to CS-1. UlDownwardCsdcQualHysteresis0 sets the hysteresis value when the

downward TBF changes from CS-3 to CS-2. UlDownwardCsdcQualHysteresis0 sets the hysteresis value when the

downward TBF changes from CS-4 to CS-3. MinCSChangeTimeGap sets the time gap when the TBF changes from one

CS to another in the same direction again. DlCsChangeILevelThreshold0 sets the interference level threshold when

the downlink TBF changes between CS-1 and CS-2. DlCsChangeILevelThreshold1 sets the interference level threshold when

the downlink TBF changes between CS-2 and CS-3. DlCsChangeILevelThreshold2 sets the interference level threshold when

the downlink TBF changes between CS-3 and CS-4.



4.2 GRPS MM ParametersThis section introduces the parameters and timers in the flows, such as Attach, Detach, RAU, Relocation, Inter-system Change, and Security Management.

4.2.1 GMM Timer

The GPRS Mobility Management (GMM) timer controls the waiting time or period during the GMM to avoid no reply from the other party due to exceptions.

T3322 (s), a Detach Response Timer, controls the time of waiting for a Detach Accept message after the network side sends a Detach Request message. If the timer expires, the network side resends the Detach Request message. This timer is defaulted to 6.

T3350 (s), an Message Resending Timer, controls the time of network side waiting for an Attach Complete, Routing Area Update Complete e, and P-TMSI Reallocation Complete message. The timer starts when the network side sends an Attach Accept, Routing Area Update Accept, and P-TMSI Reallocation Complete message, and stops when the network side receives an Attach Accept, Routing Area Update Accept, and P-TMSI Reallocation Complete message. When the timer expires, the network side resends the Attach Accept, Route Area Update Accept, and P-TMSI Reallocation Complete message for four times before the program is terminated. This timer is defaulted to 6.

T3360 (s), an Authentication and Encryption Timer, controls the time of network side waiting for an Authentication and Encryption Response message. The timer starts when the network side sends an Authentication and Encryption Request message, and stops when the network side receives an Authentication and Encryption Response message. When the timer expires, the network side resends the Authentication and Encryption Request message for four times before the program is terminated. This timer is defaulted to 6.

T3370 (s), an ID Verification Timer, controls the time of network side waiting for an ID Verification Response message. The timer starts when SGSN sends an ID Verification Request message to MS for IMSI, and stops when the network side receives an ID Verification Response message. When the timer expires, the network side resends the ID Verification Request message. The network resends the message for four times before the program is terminated. This timer is defaulted to 6.

T3313 (s), a Paging Response Timer, controls the time for network side waiting for paging response. If the timer expires, the network side resends the Paging Request message. This timer is defaulted to 6. The period of



timer T3313 must be considered as well as the resending times. The operators decide the resending times.

T3314 (s), a Ready Timer, controls the interval when two continuous layer 3 PDUs are received. Before the timer expires, if the network sends new layer 3 PDU to the MS, the system pages the user. Otherwise, the network side is enforced to enter the STANDBY state. This timer is defaulted to 44. The value in the MS is greater than that in the network side.

T3312 (min), a Periodical Route Update Timer, controls the interval for MS periodically updating the timer. This timer is also delivered to MS when the network sends an Attach Accept or Route Update Accept message to MS. It is defaulted to 54 minutes.

MSRCHTMR (min) controls the time for MS reaching the timer. It is defaulted to 58 minutes (4 min greater than T3312).

PTMSITMR (h) is a PTMSI Reallocation Timer. It ranges from 0 to 24, and defaulted to 0. 0 means no P-TMSI reallocation flow.

4.2.2 BSSAPP Timer Parameters

The GPRS system defaults lengths of BSSAPP timers during the initialization. The default values are recommended by protocol, so the users need not modify them.

The description of parameters of BSSAPP timers is as follows:

T6_1 (s), a Location Update Timer, controls the time of waiting for a Location Update Response at Gs Interface message. It is defaulted to 15.

T8 (s), a GPRS Detach Timer, controls the time of waiting for a GPRS Detach Response at Gs Interface message. If the timer expires, the SGSN resends the GPRS Detach Request message. This timer is defaulted to 4.

T9 (s), an Explicit IMSI Detach Timer, controls the time of waiting for an Explicit IMSI Detach Response at Gs Interface message. If the timer expires, the SGSN resends the Explicit IMSI Detach Request message. This timer is defaulted to 4.

T10 (s), an Implicit IMSI Detach Timer, controls the time of waiting for an Implicit IMSI Detach Response at Gs Interface message. If the timer expires, SGSN resends the Implicit IMSI Detach Request message. This timer is defaulted to 4.

T12_1 (s), a SGSN Reset Flag Timer, protects SGSN reset flag. When SGSN is reset, the Flag is set to TRUE and the timer starts. When the timer expires, the Flag is set to FALSE. This timer is defaulted to 8.

T12_2 (s), a SGSN Reset VLR Response Timer, controls the time of waiting for a SGSN Reset Response at Gs Interface message. If the timer expires, SGSN resends the SGSN Reset Indication message. This timer is



defaulted to 4.

4.3 GPRS Session Management Parameters

4.3.1 Introduction to Session Management Function

Session Management (SM) establishes, modifies, and releases the tunnel between SGSN and GGSN. 3G-SGSN SM establishes, modifies, and releases the radio access bearer (RAB) between SGSN and RNC/MS.

SM includes functions as follows:

PDP context activation PDP context modification PDP context deactivation PDP context preservation

4.3.2 SM Parameters Optimization

The SM parameters include contents as follows:

Item 1 is the software parameter of SM. Other items are configuration data between SM and GGSN and router

network. The data is configured based on the actual network conditions. Item 5, the Interconnection PLMN Control table, controls other PLMN users

to access the GPRS network during the PDP activation (including MS-originated activation, secondary activation and network side activation).

The description of parameters is as follows:

4.3.2 shows the session management status in MS.



PDP-ACTIVE- PENDING

PDP-ACTIVE

PDP-INACTIVE

PDP-INACTIVE- PENDING

DR (ACTIV. PDP CONTX. REQ)

DI (ACTIV. PDP CONTX. REJ) DI (DEACTIV. PDP CONTX. REQ)

DR: GMMSM-DATA-REQUEST (Message), i.e. message sent by an MS DI: GMMSM-DATA-INDICATION (Message), i.e. message received by an MS

DI (DEACTIV. PDP CONTX. REQ)

DR (DEACTIV. PDP CONTX. ACC)

DI (DEACTIV. PDP CONTX. ACC)


DR (MOD PDP CONTXT ACC)

DI (ACTIV. PDP CONTX. ACC) DR (DEACTIV. PDP CONTX. REQ)

DI (MOD PDP CONTXT REQ) PDP-MODIFY-PENDING

DR (MOD. PDP CONTX. REQ)

DI (REQ PDP CONTX. ACTIV)

DR (ACTIV. PDP CONTX. REQ)

DR (DEACTIV. PDP CONTX. REQ)

DI(MOD. PDP CONTX. REJ)

DI(MOD. PDP CONTX. ACC)

Figure 1.2 Session management status in MS

4.3.2 shows the session management status in MS.



DR: GMMSM-DATA-REQUEST (Message), i.e. message sent by network DI: GMMSM-DATA-INDICATION (Message), i.e. message received by the network

PDP-INACTIVE- PEND

DR (DEACTIV. PDP CONTX. REQ) DI (DEACTIV. PDP CONTX. ACC)



DI (ACTIV. PDP CONTX. REQ) DR (ACTIV. PDP CONTX. ACC)

PDP ACTIVE

PDP-MODIFY- PEND

DR (MODIFY. PDP CONTX. REQ)

DI (MODIFY. PDP CONTX. ACC)

PDP-ACTIVE- PEND

DR (REQ PDP CONTX. ACTIV)

PDP-INACTIVE

DI (ACTIV. PDP CONTX. REQ)

DR (ACTIV. PDP CONTX. ACC)

DR (ACTIV. PDP CONTX. REJ)

DR (MOD PDP CONTXT REJ)

DI (MOD PDP CONTXT REQ)



DI (REQ PDP CONTX. ACTIV. REJ)

DR (MOD PDP CONTXT ACC)

Session management status in network

PT is the peak traffic of default QoS supported by GSN. It ranges from 1 to 9, and defaulted to 9. The value meanings are as follows:

Table 2.1 Meanings of different PTs

Value Peak traffic (octet/s)

1 1000

2 2000

3 4000

4 8000

5 16000

6 32000

7 64000

8 128000

9 256000 MT is the mean traffic of default QoS supported by SGSN. It is 31 and

ranges from 1 to 18. The value meanings are as follows:

Table 2.2 Meaning of different MTs

Value Mean traffic (octet/h)

1 100



Value Mean traffic (octet/h)

2 200

3 500

4 1000

5 2000

6 5000

7 10000

8 20000

9 50000

10 100000

11 200000

12 500000

13 1000000

14 2000000

15 5000000

16 10000000

17 20000000

18 50000000

31 Best effort TC is the traffic class of default QoS traffic supported by SGSN. It ranges

from 1 to 4. 1 means session class. 2 means traffic class. 3 means interactive class. 4 means background class. 1 stands for the highest class. 4 stands for the lowest class. TC is defaulted to 1.

MAXSDU is the maximum SDU length of default QoS supported by SGSN. It ranges from 1 to 153, and defaulted to 153. The value meanings are as follows:

Table 2.3 Meanings of different MAXSDUs

Value Maximum length (octet)

1150 101500 (increased by 10)

151 1502

152 1510

153 1520 MBRUPLK is the maximum block rate on uplink of default QoS supported by

SGSN.



GBRUPLK is the guarantee block rate on uplink of default QoS supported by SGSN.

MBRDNLK is the maximum block rate on downlink of default QoS supported by SGSN.

GBRDNLK is the guarantee block rate on downlink of default QoS supported by SGSN.

MBRUPLK, GBRUPLK, MBRDNLK, and GBRDNLK range from 1 to 255, and they are defaulted to 254. The value meanings are as follows:

Table 2.4 Meanings of different rate values

Value Bit rate (kbit/s)

163 163, increased by 1

64127 64568, increased by 8

128254 5768640, increased by 64

255 0 DO is the delivery order of default QoS supported by SGSN. It ranges from

1 to 2. 1 means ordered, and 2 means unordered. Do is defaulted to 1. DESDU is the delivery error SDU of default QoS supported by SGSN. It

ranges from 1 to 3. 1 means no detection, 2 means delivery, and 3 means no delivery. DESDU is defaulted to 1.

RBET is the reserved BER of default QoS supported by SGSN. It ranges from 1 to 9, and defaulted to 9. The value meanings are as follows:

Table 2.5 Meanings of different RBETs

Value Bit rate

1 510-2

2 110-2

3 510-3

4 410-3

5 110-3

6 110-4

7 110-5

8 110-6

9 610-8

SDUER is the SDU error rate of default QoS supported by SGSN. It ranges from 1 to

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