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TTSL Orissa EGPRS Download Throughput Improved-new

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GPRS/EGPRS Download Throughput Improved For TTSL Orissa Project Copyright, 2009 ZTE Corporation.
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Page 1: TTSL Orissa EGPRS Download Throughput Improved-new

GPRS/EGPRS Download Throughput ImprovedFor TTSL Orissa Project

1. BVC Flow Control(BSC)..............................................................................................................3

2. GPRS Cell Options(Cell)..............................................................................................................5

3. SIGNAL_EUTBF : Support signaling uplink extended TBF(BSC).............................................7

4. EXT_UTBF: Support extended uplink TBF(Cell)........................................................................8

Copyright, 2009 ZTE Corporation.

Page 2: TTSL Orissa EGPRS Download Throughput Improved-new

5. Cell Reselecting Hysteresis Level(Cell).......................................................................................9

6. Edge Params(Cell)........................................................................................................................9

7. GPRS MAX initial access signal level........................................................................................11

8 The parameter of GPRS Property1(BSC Level) changed............................................................11

9 The parameter of EDGE Property(BSC Level) changed.............................................................12

10 The parameter of Site Bandwidth Limit(Cell Level) changed...................................................13

11. UPPB-DSP Congestion audit....................................................................................................14

12. The PDTCH Configuration(Cell Level) Moved.......................................................................18

13. The PDTCH Configuration(Cell Level) changed for 3 PDTCHs.............................................19

14. The Throughput Improved for 3 PDTCHs................................................................................21

15. The PDTCH Configuration(Cell Level) changed for 2 PDTCHs.............................................22

16. The Throughput Improved for 2 PDTCHs................................................................................24

17. Test Conclusion of EGPRS Download Throughput..................................................................25

Copyright, 2009 ZTE Corporation.

Page 3: TTSL Orissa EGPRS Download Throughput Improved-new

1. BVC Flow Control(BSC)

BVCFlowCtrl: BVC Flow Control Supported

BVC flow control occurs on Gb interface between SGSN and BSS, and only on downlinks. BSS

provides control parameters and SGSN executes, to avoid one BVC on BSS to abandon some LLC

data because of discard some LLC data blocks due to overtime caused from grouping channel as

too busy and to avoid new downlink LLC data because of memory resource limitations.

BSSGP counts the current leaking rate of BVC periodically (including short ;;statistics and long statistics). BVCFlowCtrl originates unconditionally if long statistics timer stops, SGSN

acknowledgement is necessary, and if discrepant range of adjacent leaking rates is over

CellFcThs. BVCFlowCtrl originates and SGSN confirmation is necessary if short statistics timer

overflows and discrepant range of adjacent leaking rates is over CellFcThs.

1). FlowCtrlMode: Flow Control Mode

There are two Modes to determine the SGSN flow control of different providers.

Mode 1: Report flow control parameters according to actual traffic on radio interface counted

at BSC

Mode 2: Report flow control parameters according to max traffic that the cell can provide

Suggestion value: Normally, we use Mode 2.

2). FlowCtlMode2Para:Parameter of Flow Control Mode2BSC reports flow control parameters according to max traffic that the cell can provide. Max value

depends on channels configured. Counting formula: channels * max traffic that every channel

can provide. This parameter is max traffic that every channel can provide, with the unit of 100

bps.

Value range: 10 ~ 1000

Copyright, 2009 ZTE Corporation.

Page 4: TTSL Orissa EGPRS Download Throughput Improved-new

Default value: 214

The Normal Value of FlowCtlMode2Para for EGPRS as below

Code

Set

Throughpu

t per TS

FlowCtlMode2Par

a

MCS-1

8.8 kbps 88

MCS-2

11.2 kbps 112

MCS-3

14.8 kbps 148

MCS-4

17.6 kbps 176

MCS-5

22.4 kbps 224

MCS-6

29.6 kbps 296

MCS-7

44.8 kbps 448

MCS-8

56.4 kbps 564

MCS-9

59.2 kbps 592

The Normal Value of FlowCtlMode2Para for GPRS as below

Code Set

Throughput per

TS

FlowCtlMode2Para

CS-1

9.05 kbps 90

CS-2

13.4 kbps 134

CS-3

15.6 kbps 156

CS-4

21.4 kbps 214

Suggestion value: for EGPRS set to 800.

Copyright, 2009 ZTE Corporation.

Page 5: TTSL Orissa EGPRS Download Throughput Improved-new

2. GPRS Cell Options(Cell)

1). T3192: T3192 timer

T3192 is used at MS side. During the packet downlink transmission, if RLC data block is the final

downlink data block to be transmitted, the network sends the RLC data block with the Final Block

Identifier (FBI) domain as 1. It contains an effective RRBP field to initialize the release of the

downlink TBF.

In acknowledged mode, the MS sends PACKET DOWNLINK ACK/NACK message whose FBI

domain is 1 on the uplink block specified by the RRBP domain.

In the unacknowledged mode, the MS sends PACKET CONTROL ACK message on the uplink

block specified by the RRBP domain. Then MS starts the T3192 timer. When T3192 stops, the

system releases the resources, stops listening to the PDCCH channel, and turns to listen the paging

channel.

If a MS receives PACKET DOWNLINK ASSIGNMENT or PACKET TIMESLOT

RECONFIGURE message from the network within the protection period of the T3192 timer, it

stops T3192 and transfer to the packet transmission status.

Value range:{ 500, 1000, 1500,0,80,120,160,200}

Default value: 500ms

Timer value must be less than the protection timer T3193 of the downlink TBF at the network

side, in order to ensure TFI uniqueness of MS at the same time.

Suggestion value: 1500ms for T3192, 1520ms for T3193

Copyright, 2009 ZTE Corporation.

Page 6: TTSL Orissa EGPRS Download Throughput Improved-new

2). DrxTimeMax: Non-DRX Mode Holding Time

This parameter belongs to GPRS cell option and is used at MS side.

When the MS changes from the packet BUSY mode to the packet IDLE mode, it should first enter

the Non-Drx mode. The DRX_TIMER_MAX parameters determine the maximum time length

for MS to stay in the Non-DRx mode.

Under the Non-Drx mode status, MS establish TBF link take short time than Drx mode status,

refer to GSM04.60-12.24

Value range: {1 s , 2 s, 4 s , 8 s , 16 s , 32 s , 64 s }

Default value: 2 s

Suggestion value: 4s

3). BsCvMax: Max Blocks Transmission in Each TS

This parameter belongs to GPRS cell option and is used at MS side.

BsCvMax indicates the value of BsCvMax parameter of Max Blocks Transmission in each TS.

This parameter determines the following:

Time length of T3198 timer used by MS. This time length is equal to the time represented by

BsCvMax.

Time length of T3200 used by MS in Non-Drx mode. This time length = 4 × time represented

by BsCvMax.

Value of N3104max = (3 × (BsCvMax+3) × Number of timeslots assigned in the uplink).

All uplink data blocks sent by MS contain the COUNT DOWN VALUE (CV) field. The network

can use this field to calculate the data blocks to be sent on current uplink TBF.

Value range:

Copyright, 2009 ZTE Corporation.

Page 7: TTSL Orissa EGPRS Download Throughput Improved-new

Default value: 15

Suggestion value: some MS can only support 0-12, so change 15 to 9.

3. SIGNAL_EUTBF : Support signaling

uplink extended TBF(BSC)

This parameter represents whether BSC supports signaling uplink extended TBF. Normally, the

uplink signaling message transmission was finished, uplink TBF link was released immediately to

free TFI resource. Uplink signaling extended TBF enabled can hold the link and TFI resource for

some time, if MS needs transmission signaling again, it can use the TFI resource. The uplink TBF

established constantly will affect downlink throughput.

Value range: Check/Uncheck

Check: Support signaling uplink extended TBF Uncheck: Does not support signaling uplink

extended TBF

Default value: Uncheck,

Copyright, 2009 ZTE Corporation.

Value Meaning0 Time length of one block

1 Time length of one block

… …

15 Time length of 15 blocks

Page 8: TTSL Orissa EGPRS Download Throughput Improved-new

Suggestion value: Check

4. EXT_UTBF: Support extended uplink

TBF(Cell)

This parameter represents whether extended uplink TBF is supported in the cell.

If support extended uplink TBF, after uplink TBF link have sent last RLC data block, the link

don’t release for short time, if there have data to send, the link will be used, new TBF link

establishment is not necessary, it save the time to load data.

Value range: Check/Uncheck

Check: extended uplink TBF is active in cell; Uncheck: extended uplink TBF is not active in cell

Default value: Uncheck,

Suggestion value: Check

Copyright, 2009 ZTE Corporation.

Page 9: TTSL Orissa EGPRS Download Throughput Improved-new

5. Cell Reselecting Hysteresis Level(Cell)

If Mobile is in data service and does Cell Reselection, the MS will stop data transmission about 4-

10seconds. In order to decrease cell reselection, need to increase the ReselHysteresis parameter to

avoid cell reselection frequently.

6. Edge Params(Cell)

1). Support EGPRS_PACKET_CHANNEL_REQUEST Access Program

(EGPRSPacketChReq)If Cell supports EGPRS_PACKET_CHANNEL_REQUEST Access Program, EGPRS mobile can

set up packet access program on RACH or PRACH(if PBCCH is configured)

Enabled this function can improve uplink throughput.

Value range: Check/Uncheck

Check: EGPRS_PACKET_CHANNEL_REQUEST Access Program is active in cell; Uncheck:

Copyright, 2009 ZTE Corporation.

Page 10: TTSL Orissa EGPRS Download Throughput Improved-new

EGPRS_PACKET_CHANNEL_REQUEST Access Program is not active in cell

Default value: Uncheck,

Suggestion value: Check

2). EGPRS Phone Quality Measure Mode (LinkQuaMeaMode)

LinkQuaMeaMode indicates the measurement report mode of EGPRS MS in the cell. EGPRS

measurement could be performed based on each impulse, which is to measure by the granularity

of BURST. The feature of rapid EGPRS measurement makes the network side be able to respond

the change of radio environment quickly.

EGPRS MS have two kinds of report mode, based on BURST or based on TBF.

Reporting parameters based on BURST are MEAN_BEP_TNx( 0-7) (error bit rate per time

slot)and I_LEVEL_TN(0-7).Reporting parameters based on TBF are MEAN_BEP (average error bit rate of the radio block)

and CV_BEP (variance coefficient of radio block error bit rate).

Value range: 0-3.

0. Report MEAN_BEP and CV_BEP

1. Only report I_LEVEL_TN(0-7)2. Only report MEAN_BEP_TNx(0-7)3. Report MEAN_BEP_TNx(0-7)and I_LEVEL_TN(0-7)Default value: 2

In report mode, 0 means report based on TBF, 1~3 means report based on timeslot(BURST).

Currently in report based on timeslot, omission of report occurs at some terminals, which seriously

affects adjustment of coding mode(MCS1-9)

Suggestion: 0 based on TBF report mode.

3). Average filter period for uplink/downlink BEP

In EGPRS system, EGPRS MS will determine to report the MEAN_REP_AV (average error bit

rate of the radio block) and CV_BEP_AV (variance coefficient of radio block error bit rate) under

the whole TBF, or the measurement data per time slot MEAN_BEP_TNx (0-7).

The specification defines the formula of these measurement data (refer to GSM05.08 10.2.3.2.1).

There is an oblivion factor e, whose value is defined by average period of BEP filter.

Average filter period for BEP calculation is an oblivion factor e, it is the weight of measurement

report, the value is more, and the reliability of BEP is high.

Value Range: Average filter period for downlink BEP {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,14,

15}, Average filter period for uplink BEP {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

Default value: both are 4 blocks.

Suggestion value: both are 10 blocks.

Copyright, 2009 ZTE Corporation.

Page 11: TTSL Orissa EGPRS Download Throughput Improved-new

7. GPRS MAX initial access signal level

GPRS MAX initial access signal level set to 5 for GSM900MHz, set to 2 for DCS1800MHz.

Suggestion value: Changing it from 5 to 2.

8 The parameter of GPRS Property1(BSC

Level) changed

Copyright, 2009 ZTE Corporation.

Page 12: TTSL Orissa EGPRS Download Throughput Improved-new

9 The parameter of EDGE Property(BSC

Level) changed

In order to improve the GPRS\EGPRS throughput, we suggest changing below parameter to

BSC.

The group parameter of EDGE Property is as below. (Notes: these parameter are only

available for iBSC, for V2 BSC they are not working).

RS: Uplink throughput weight value at Gb interface, the dynamic Abis adjustment parameter.

RR: Downlink throughput weight value at Gb interface, the dynamic Abis adjustment

parameter.

RA: Weight value of EGPRS MS accessing request times, the dynamic Abis adjustment

parameter.

RM: Weight value of high-bandwidth request times, the dynamic Abis adjustment parameter.

RB: Weight value of the highest bandwidth usage, the dynamic Abis adjustment parameter.

RG and RE: This parameter defines weights of GPRS carrier proportion,

RS+RR+RA+RM+RB+RG+RE must be equal to 100

Copyright, 2009 ZTE Corporation.

Page 13: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: Edge Property parameters

10 The parameter of Site Bandwidth

Limit(Cell Level) changed

In order to give effective control, we will change the Site parameter of Bandwidth Limit(kb)

as below.

Copyright, 2009 ZTE Corporation.

Page 14: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: Site Bandwidth Limit parameter.

11. UPPB-DSP Congestion audit

Normally, we can use below formula to check GPRS/EGPRS congestion.

1). RR Resource(PDTCH) Congestion Rate

(C901170008+ C901170037+ C901180008+ C901180037+ C901190016+ C901190065+

C901200016+ C901200065)*100/(C900040108+C900040112+C900040114+ C900040118+

C900040120+ C900040126 + C900040128+ C900040134)

([Number of GPRS DL TBF establishment failure due to RR congestion]+[Number of GPRS DL

TBF resource reallocation failure due to RR congestion for LLC transmission]+[Number of

EGPRS DL TBF establishment failure due to RR congestion]+[Number of EGPRS DL TBF

resource reallocation failure due to RR congestion for LLC transmission]+[Number of GPRS UL

TBF establishment failure due to RR congestion]+[Number of GPRS UL TBF resource

reallocation failure due to RR congestion for resource request]+[Number of EGPRS UL TBF

establishment failure due to RR congestion]+[Number of EGPRS UL TBF resource reallocation

failure due to RR congestion for resource request])/([Number of GPRS DL TBF establishment

Copyright, 2009 ZTE Corporation.

Page 15: TTSL Orissa EGPRS Download Throughput Improved-new

requests]+[Number of GPRS DL TBF resource reallocation requests due to LLC transmission]+

[Number of EGPRS DL TBF establishment requests]+[Number of EGPRS DL TBF resource

reallocation requests due to LLC transmission]+[Number of GPRS UL TBF establishment

requests]+[Number of GPRS UL TBF resource reallocation requests for resource request]+

[Number of EGPRS UL TBF establishment requests]+[Number of EGPRS UL TBF resource

reallocation requests for resource request])

2). Abis Resource Congestion Rate

(C901170007+ C901170036+ C901180007+ C901180036+ C901190015+ C901190064+

C901200015+ C901200064)*100/(C900040108+C900040112+C900040114+ C900040118+

C900040120+ C900040126 + C900040128+ C900040134)

([Number of GPRS DL TBF establishment failure due to Abis congestion]+[Number of GPRS DL

TBF resource reallocation failure due to Abis congestion for LLC transmission]+[Number of

EGPRS DL TBF establishment failure due to Abis congestion]+[Number of EGPRS DL TBF

resource reallocation failure due to Abis congestion for LLC transmission]+[Number of GPRS UL

TBF establishment failure due to Abis congestion]+[Number of GPRS UL TBF resource

reallocation failure due to Abis congestion for resource request]+[Number of EGPRS UL TBF

establishment failure due to Abis congestion]+[Number of EGPRS UL TBF resource reallocation

failure due to Abis congestion for resource request])/([Number of GPRS DL TBF establishment

requests]+[Number of GPRS DL TBF resource reallocation requests due to LLC transmission]+

[Number of EGPRS DL TBF establishment requests]+[Number of EGPRS DL TBF resource

reallocation requests due to LLC transmission]+[Number of GPRS UL TBF establishment

requests]+[Number of GPRS UL TBF resource reallocation requests for resource request]+

[Number of EGPRS UL TBF establishment requests]+[Number of EGPRS UL TBF resource

reallocation requests for resource request])

3). UPPB DSP Resource Congestion Rate

One UPPB have 14 DSP Units, the maximum process capacity of each DSP is 160 Abis TS of

16kbps( one DSP = 160*16kbps), if enable GPRS CS3/4, one DSP can support maximum 80

dynamic and static channels, if open EDGE service, one DSP can support maximum 40 dynamic

and static channels.

If DSP overload, some PDTCH will not be occupied, that means you have configured 4 static

PDTCH channels, you can only occupy less than 4 PDTCH channels.

Suggestion: there can configure 10 to 15 sectors to one DSP in UPPB board.

(C901170009+ C901170038+ C901180009+ C901180038+ C901190017+ C901190066+

C901200017+ C901200066)*100/(C900040108+C900040112+C900040114+ C900040118+

C900040120+ C900040126 + C900040128+ C900040134)

([Number of GPRS DL TBF establishment failure due to UPPB-DSP channel congestion]+

[Number of GPRS DL TBF resource reallocation failure due to UPPB-DSP channel congestion for

LLC transmission]+[Number of EGPRS DL TBF establishment failure due to UPPB-DSP channel

congestion]+[Number of EGPRS DL TBF resource reallocation failure due to UPPB-DSP channel

Copyright, 2009 ZTE Corporation.

Page 16: TTSL Orissa EGPRS Download Throughput Improved-new

congestion for LLC transmission]+[Number of GPRS UL TBF establishment failure due to

UPPB-DSP channel congestion]+[Number of GPRS UL TBF resource reallocation failure due to

UPPB-DSP channel congestion for resource request]+[Number of EGPRS UL TBF establishment

failure due to UPPB-DSP channel congestion]+[Number of EGPRS UL TBF resource reallocation

failure due to UPPB-DSP channel congestion for resource request])/([Number of GPRS DL TBF

establishment requests]+[Number of GPRS DL TBF resource reallocation requests due to LLC

transmission]+[Number of EGPRS DL TBF establishment requests]+[Number of EGPRS DL TBF

resource reallocation requests due to LLC transmission]+[Number of GPRS UL TBF

establishment requests]+[Number of GPRS UL TBF resource reallocation requests for resource

request]+[Number of EGPRS UL TBF establishment requests]+[Number of EGPRS UL TBF

resource reallocation requests for resource request])

4) The Max Simultaneous Existing TBF numbers

C901000048 Downlink Max GPRS TBF Number of Simultaneous Establishment

C901000050 Downlink Max EGPRS TBF Number of Simultaneous Establishment

C901010046 Uplink Max GPRS TBF Number of Simultaneous Establishment

C901010048 Uplink Max EGPRS TBF Number of Simultaneous Establishment

5) PDTCH Utillization

C900040140/ C900040136

We had defined above formula and exported performance data, and found the UPPB-DSP have

congestion for some cells.

BSC ID SITE ID Bts ID

local cell

ID

UPPB DSP

Resource

Congestio

n Rate%

Belong to

DSP No

1 8 2 30172 5.81% 11

1 48 1 30461 50.00% 11

1 116 1 30851 7.69% 9

1 22 1 30351 12.50% 10

1 39 2 30522 5.88% 11

1 89 3 30933 6.67% 14

1 24 3 30233 8.57% 10

1 142 1 30911 5.88% 9

1 151 3 31173 11.76% 9

1 24 3 30233 5.95% 10

1 21 3 30593 12.82% 10

1 43 3 30513 7.69% 11

1 48 3 30463 5.56% 11

1 21 3 30593 18.18% 10

1 40 4 30384 12.50% 11

1 71 3 33243 20.00% 13

Copyright, 2009 ZTE Corporation.

Page 17: TTSL Orissa EGPRS Download Throughput Improved-new

1 77 3 33043 5.26% 11

1 21 3 30593 8.45% 10

1 24 3 30233 9.88% 10

1 208 1 43361 9.68% 13

1 118 3 30663 6.38% 9

1 141 2 31162 9.52% 9

1 8 3 30173 11.36% 11

1 21 3 30593 17.24% 10

1 74 2 33422 25.00% 13

1 120 2 30992 5.26% 9

1 144 3 33573 6.12% 9

1 8 2 30172 10.34% 11

1 35 1 30341 8.11% 11

1 38 1 30061 16.00% 11

1 39 1 30521 9.09% 11

1 43 3 30513 6.67% 11

1 6 1 30211 5.56% 11

1 27 2 31582 6.25% 11

1 47 3 30453 7.14% 11

1 6 1 30211 8.70% 11

1 90 1 30811 12.50% 14

1 24 3 30233 5.88% 10

1 128 3 30713 8.33% 9

1 162 1 33561 6.25% 9

From OMCR we can export Network Planning Data table, and fond DSP No. the cell belong to.

From above table, we can statistic how many sectors connected to the DSP.

Copyright, 2009 ZTE Corporation.

Page 18: TTSL Orissa EGPRS Download Throughput Improved-new

DSP NO.

Total Sector

Numbers

0 19 75

10 6811 6712 1913 7114 5515 616 9717 2018 2119 1320 3321 1222 1

From above table, we know the DSP 9,10,11,13,14 and 16 have more sectors connected to them.

The DSP 16 have 97 cells connected to it, because there have a few subscriber to use GPRS

service, so there haven’t DSP congestion.

So we suggest move above DSP congestion cells to DSP 15,19,21,22 to balance the DSP

process loading.

As below, we changed the configuration of DSP, the DSP congestion is improved.

12. The PDTCH Configuration(Cell Level)

Moved

The Dynamic TS property used to provide more PDTCH to support data transmit, if the TCH

channel is enough to support voice service, the system will shift to dynamic TCH timeslots to

PDTCH. The shift action will happen at the before or back TCHs at the static PDTCH channel.

If you configure as below figuration, the system only shift the before dynamic TCH timeslots

Copyright, 2009 ZTE Corporation.

Page 19: TTSL Orissa EGPRS Download Throughput Improved-new

to PDTCH, for this case, some shift actions will failure, because the USF flag bit can’t be moved

to other PDTCHs.

Figure: the Dynamic TS property only can shift forth TCH to PDTCH.

So we suggest move the static PDTCH to the middle between the TCHs with Dynamic TS,

the system is easy to shift the back or forth TCHs with dynamic TS property to PDTCH. The

configuration is as below.

Figure: the Dynamic TS property can shift both the back or forth TCH to PDTCH.

13. The PDTCH Configuration(Cell Level)

changed for 3 PDTCHs

Because the modulations of GPRS(CS-1 to CS-4) and EGPRS(MCS-1 to MCS-4) are

GMSK, and EGPRS(MCS-5 to MCS-6) is with 8-PSK modulation. The 8-PSK gives the EGPRS

high throughput, if EGPRS and GPRS are same with GMSK, the throughput of EGPRS will be

lower than the GPRS.

Table: the Modulation and Bit Rate of GPRS and EGPRS.

Modulative Coding modulation RLC FEC User bit Rate (bps) Family

Copyright, 2009 ZTE Corporation.

Page 20: TTSL Orissa EGPRS Download Throughput Improved-new

Mode schemeBlks/Ra

dio Blk

Code

Ratebits/20ms

GPRS

CS-1

GMSK

1 0.45 160 8,000 -

CS-2 1 0.65 240 12,000 -

CS-3 1 0.75 288 14,400 -

CS-4 1 1 400 20,000 -

EGPRS

MCS-1 1 0.53 176 8,800 C

MCS-2 1 0.66 224 11,200 B

MCS-3 1 0.85 296 14,800 A

MCS-4 1 1 352 17,600 C

MCS-5

8-PSK

1 0.38 448 22,400 B

MCS-6 1 0.49 592 29,600 A

MCS-7 2 0.76 448+448 44,800 B

MCS-8 2 0.92 544+544 54,400 A

MCS-9 2 1 592+592 59,200 A

We configure the PDTCH to the site with both GPRS and EGPRS supported, if they shared

the PDTCH, the modulation of data coding will use GMSK to transfer data, that means the

subscriber with 8-PSK will change its modulation to GMSK, so the throughput of the subscriber

with 8-PSK will be decreased. The configuration is just as below.

Figure: the subscribers of both GPRS and EGPRS will share the PDTCH to transfer data.

Because the PS Service Preference Property is set to No Preference, the subscribers of both

GPRS and EGPRS will share the PDTCH to transmit data, the modulation will use GMSK to code

data, the throughput will be lower.

So we must change the configuration to support GPRS and EGPRS subscribers separately, the

subscribers to occupy the different PDTCH, just like below two figurations.

Copyright, 2009 ZTE Corporation.

Page 21: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: the subscribers of EGPRS occupy the PDTCH with EDGE Dedicated Property.

Above figuration indicates the subscribers of EGPRS will occupy the PDTCH with EDGE

Dedicated Property. If the C/I is enough better to support the 8-PSK coding, the coding set of data

transfer will use MCS-5 to MCS-9, so the throughput will be increased.

In order to support the GPRS subscribers, we will configure the GPRS preference PDTCH to it,

just like below figuration.

Figure: the subscribers of GPRS occupy the PDTCH with GPRS Preference Property.

So there have 3 PDTCH to support data transfer, the 2 PDTCHs are with EDGE dedicated and 1

PDTCH is with GPRS preference property in one sector.

Copyright, 2009 ZTE Corporation.

Page 22: TTSL Orissa EGPRS Download Throughput Improved-new

14. The Throughput Improved for 3

PDTCHs

After adjust above parameters and reconfiguration, the Mean Rate of EGPRS LLC DownLink

Throughput of summarization from 7:00 to 24:00 by Cell is improved as below.

Mean Rate of EGPRS LLC DL throughput(kbps)BSC9

10000350006000085000

110000135000160000185000210000

10- J

un

11- J

un

12- J

un

13- J

un

14- J

un

15- J

un

16- J

un

17- J

un

18- J

un

19- J

un

20- J

un

Mean Rate of EGPRS LLC DL throughput(kbps)

137102133549136841143349143093120059168660175706161752200255

2010-6-10

2010-6-11

2010-6-12

2010-6-13

2010-6-14

2010-6-16

2010-6-17

2010-6-18

2010-6-19

2010-6-20

Figure: BSC9 of Mean Rate of EGPRS LLC Downlink Throughput improved.

Copyright, 2009 ZTE Corporation.

Page 23: TTSL Orissa EGPRS Download Throughput Improved-new

Mean Rate of EGPRS LLC DL throughput(kbps)BSC7

150000155000160000165000170000175000180000185000190000195000200000

10- J

un

11- J

un

12- J

un

13- J

un

14- J

un

15- J

un

16- J

un

17- J

un

18- J

un

19- J

un

20- J

un

Mean Rate of EGPRS LLC DL throughput(kbps)

181297 185345 178324 185145 180824 147880 187513 196694 192351 197421

2010-6-10

2010-6-11

2010-6-12

2010-6-13

2010-6-14

2010-6-16

2010-6-17

2010-6-18

2010-6-19

2010-6-20

Figure: BSC7 of Mean Rate of EGPRS LLC Downlink Throughput improved.

15. The PDTCH Configuration(Cell Level)

changed for 2 PDTCHs

Before we have added one more PDTCH to support data with GPRS preference property in

one sector, so one TCH is decreased to support voice call in one sector. In order to avoid the

customer have complaint for the TCH decreased, we have changed one PDTCH with EDGE

dedicated channel to TCH channel. So in one sector there has only 2 PDTCH support data transfer,

the configurations are as below.

Before changing, in one sector there have 2 PDTCH support EDGE mobile and 1 PDTCH

support GPRS mobile.

Copyright, 2009 ZTE Corporation.

Page 24: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: in one sector there have 2 PDTCH support EGDE mobile and 1PDTCH support GPRS

mobile.

After changing, in one sector there have only 1 PDTCH support EDGE mobile and 1 PDTCH

support GPRS mobile.

Copyright, 2009 ZTE Corporation.

Page 25: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: in one sector there have only 1 PDTCH support EGDE mobile and 1PDTCH support

GPRS mobile.

16. The Throughput Improved for 2

PDTCHs

After changing from 3 PDTCH channels to 2 PDTCH channels in one sector, the Mean Rate of

Copyright, 2009 ZTE Corporation.

Page 26: TTSL Orissa EGPRS Download Throughput Improved-new

EGPRS LLC DownLink Throughput of summarization from 7:00 to 24:00 by Cell is same as

below.

Mean Rate of EGPRS LLC DL throughput(kbps)BSC9

100000110000120000130000140000150000160000170000180000190000200000210000

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Mean Rate of EGPRS LLC DL throughput (kbps)

137102 133549 136841 143349 143093 120059 168660 175706 161752 200255 167678 166143 160242 161366 162500

2010-6- 10

2010-6- 11

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2010-6- 25

Figure: BSC9 of Mean Rate of EGPRS LLC Downlink Throughput.

Mean Rate of EGPRS LLC DL throughput(kbps)B8

165000

170000

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Mean Rate of EGPRS LLC DL throughput(kbps)

181954188208181190194658193982189402199302187748199171199804204267204806195568196447

10- 6-11

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Figure: BSC8 of Mean Rate of EGPRS LLC Downlink Throughput.

Mean Rate of EGPRS LLC DL throughput(kbps)BSC7

150000155000160000165000170000175000180000185000190000195000200000

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Mean Rate of EGPRS LLC DL throughput (kbps)

181297185345178324185145180824147880187513196694192351197421188743189510182875189102197509

2010-6- 10

2010-6- 11

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2010-6- 21

2010-6- 22

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2010-6- 25

Copyright, 2009 ZTE Corporation.

Page 27: TTSL Orissa EGPRS Download Throughput Improved-new

Figure: BSC7 of Mean Rate of EGPRS LLC Downlink Throughput.

Mean Rate of EGPRS LLC DL throughput (kbps)BSC6

150000

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Mean Rate of EGPRS LLC DL throughput (kbps)

190840. 77 239575. 66 257611. 73 251368. 63 246125. 03 244249. 74 236479. 53 244116. 71

2010- 6- 18 2010- 6- 19 2010- 6- 20 2010- 6- 21 2010- 6- 22 2010- 6- 23 2010- 6- 24 2010- 6- 25

Figure: BSC6 of Mean Rate of EGPRS LLC Downlink Throughput.

17. Test Conclusion of EGPRS Download

Throughput

After changing above parameters and balance the DSP configuration, we have got best download

throughput.

Copyright, 2009 ZTE Corporation.

Page 28: TTSL Orissa EGPRS Download Throughput Improved-new

Copyright, 2009 ZTE Corporation.


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