55982669 egprs radio networks dimension ing and planning guidelines v 2 0

8/10/2019 55982669 EGPRS Radio Networks Dimension Ing and Planning Guidelines v 2 0

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C & I(E)GPRS RADIO NETWORKS - DIM. AND PLANNING Version 2.0

(E)GPRS Radio Networks Dimensioning and PlanningGuidelines (PCU1 and PCU2 Rel.1) v2.0

Owner: (E)GPRS Program - Ville SalomaaScope: EDGE Radio Networks - Planning TheoryOriginator: C & IStatus: Version 2.0Document ID:Location:

Change History

Issue Date Handled by CommentsVer. 1.0 24.10.2005 Pal SzabadszallasiVer. 2.0 18.12.2006 Pal Szabadszallasi

Approved byVille Salomaa (E)GPRS Program


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1. Introduction .................................................................................................................................... 6

1.1 (E)GPRS BSS Dimensioning and Planning............................................................................. 61.2 DSP Resource Management Issues in PCU2 ......................................................................... 72. Operators Business Plan............................................................................................................... 8

2.1 Number of Users with Traffic Volume...................................................................................... 82.2 Services with QoS both on CSW and PSW............................................................................. 82.3 Controlled Investment.............................................................................................................. 9

3. Network Audit............................................................................................................................... 103.1 Hardware Audit and Considerations...................................................................................... 12

3.1.1 BSC Types ..................................................................................................................... 123.1.2 PCU and PCU2 .............................................................................................................. 133.1.3 BTS Types...................................................................................................................... 143.1.3.1 UltraSite Baseband Units............................................................................................ 143.1.4 TRX Capabilities............................................................................................................. 16

3.1.4.1 UltraSite TRX Capabilities .......................................................................................... 163.1.4.2 MetroSite TRX Capabilities......................................................................................... 173.1.4.3 TALKFamily TRX Capabilities .................................................................................... 17

3.2 GSM Feature Audit and Considerations................................................................................ 183.2.1 MultiBCF and Common BCCH....................................................................................... 183.2.2 BB and RF Hopping ....................................................................................................... 193.2.3 Extended Cell ................................................................................................................. 193.2.4 FR/DR/HR ...................................................................................................................... 193.2.5 AMR ............................................................................................................................... 193.2.6 IUO/IFH .......................................................................................................................... 20

3.3 (E)GPRS Feature Audit and Considerations......................................................................... 213.3.1 PBCCH........................................................................................................................... 213.3.2 NMO1............................................................................................................................. 21

3.3.3 EPCR ............................................................................................................................. 223.3.4 NCCR ............................................................................................................................. 223.3.5 NACC ............................................................................................................................. 223.3.6 QoS ................................................................................................................................ 223.3.7 EQoS.............................................................................................................................. 233.3.8 GPRS CS1-4 .................................................................................................................. 233.3.9 DA with USF4................................................................................................................. 233.3.10 EDA ............................................................................................................................ 233.3.11 HMC............................................................................................................................ 243.3.12 DTM............................................................................................................................ 24

3.4 Coverage and Interference Audit Air Interface ................................................................... 263.4.1 Signal Level Estimation .................................................................................................. 263.4.1.1 Planning Tool Calculations ......................................................................................... 26

3.4.1.2 Drive Test Measurements........................................................................................... 273.4.1.3 OSS Measurements ................................................................................................... 283.4.1.4 GPRS.......................................................................................................................... 283.4.1.5 EGPRS ....................................................................................................................... 283.4.2 Interference Dependency............................................................................................... 293.4.2.1 GPRS.......................................................................................................................... 293.4.2.2 EGPRS ....................................................................................................................... 293.4.3 TSL Data Rate Dependency on GSM Functionality ....................................................... 30

3.5 Abis Signaling Audit TRXSIG ............................................................................................. 313.6 EDAP Audit............................................................................................................................ 313.7 PCU Audit.............................................................................................................................. 313.8 Conclusion on BSS Network Audit ........................................................................................ 31


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3.9 Gb and SGSN (SG6) Audit.................................................................................................... 323.9.1 Gb Interface.................................................................................................................... 32

3.9.2 SGSN and PAPU ........................................................................................................... 324. Deployment Plan.......................................................................................................................... 334.1 Deployment Planning Steps for Cells .................................................................................... 33

4.1.1 Hardware and Software Considerations......................................................................... 334.1.2 Signaling......................................................................................................................... 344.1.3 CDEF Location (BCCH or non BCCH TRX)................................................................... 344.1.4 CDEF Size Definition...................................................................................................... 344.1.5 CDED Size Definition ..................................................................................................... 354.1.6 GTRX, GENA and EGENA Parameter Setup................................................................. 35

4.2 Deployment Planning Steps for Segments (MultiBCF/CBCCH)............................................ 354.2.1 Hardware and Software Considerations......................................................................... 354.2.2 Signaling......................................................................................................................... 354.2.3 BTS Selection to Separate GPRS and EGPRS (and CSW) .......................................... 35

4.2.4 CDEF Location (BCCH or non BCCH TRX)................................................................... 354.2.5 CDEF Size Definition...................................................................................................... 364.2.6 CDED Size Definition ..................................................................................................... 364.2.7 GTRX, GENA and EGENA Parameter Setup................................................................. 36

4.3 Cell Option Example.............................................................................................................. 374.3.1 Cell Option Example Description.................................................................................... 37

4.4 Segment Option Example...................................................................................................... 394.4.1 Segment Option Example Description ........................................................................... 39

5. Connectivity Capacity Dimensioning............................................................................................ 415.1 Introduction............................................................................................................................ 415.2 Dimensioning Inputs .............................................................................................................. 425.3 Air Interface Capacity ............................................................................................................ 44

5.3.1 Configuration before (E)GPRS....................................................................................... 44

5.3.2 (E)PRS Deployment Scenarios ...................................................................................... 455.3.3 Available Capacity.......................................................................................................... 465.3.3.1 2+2+2 Configuration Calculations............................................................................... 475.3.3.2 4+4+4 Configuration Calculations............................................................................... 485.3.4 Required Capacity.......................................................................................................... 495.3.4.1 2+2+2 Configuration Calculations............................................................................... 495.3.4.2 4+4+4 Configuration Calculations............................................................................... 49

5.4 Connectivity Capacity ............................................................................................................ 505.4.1 CDEF.............................................................................................................................. 505.4.1.1 2+2+2 Configuration Calculations............................................................................... 505.4.1.2 4+4+4 Configuration Calculations............................................................................... 505.4.2 EDAP.............................................................................................................................. 505.4.2.1 General EDAP size considerations............................................................................. 50

5.4.2.2 Abis TSL Allocation..................................................................................................... 525.4.3 PCU................................................................................................................................ 545.4.3.1 PCU Dimensioning Scenario 1 (Simple Dimensioning) .............................................. 545.4.3.2 PCU Dimensioning Scenario 2 (Partial Planning)....................................................... 565.4.4 Gb Link Dimensioning .................................................................................................... 595.4.4.1 Gb Link Dimensioning based on Average of EDAP Sizes.......................................... 595.4.4.2 Gb Link Dimensioning based on Exact EDAP to PCU Mapping................................. 60

5.5 Summary ............................................................................................................................... 626. Resource Allocation Planning ...................................................................................................... 63

6.1 Cell Selection......................................................................................................................... 636.1.1 C1 and C2 ...................................................................................................................... 636.1.2 C31/C32 ......................................................................................................................... 63


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6.1.3 NCCR ............................................................................................................................. 636.2 BTS Selection........................................................................................................................ 63

6.3 Scheduling............................................................................................................................. 647. Mobility Planning.......................................................................................................................... 657.1 LA and RA Planning .............................................................................................................. 667.2 Cell-reselect Hysteresis......................................................................................................... 667.3 NACC .................................................................................................................................... 66

8. Parameter Set for Network Launch.............................................................................................. 679. References................................................................................................................................... 68


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1. INTRODUCTION

The purpose of (E)GPRS Radio Networks Dimensioning and Planning Guidelines is todescribe the (E)GPRS Radio Network Planning activities and requirements with PCU1 andPCU2 Release1.

This document is part of (E)GPRS Radio Networks planning document set, which isseparated on the following way:

- (E)GPRS Radio Networks Planning Theory

- (E)GPRS Radio Networks Dimensioning and Planning Guidelines

- (E)GPRS Radio Networks Optimization Guidelines

These documents are strongly linked to each other, thus the separated usage is not

recommended.

1.1 (E)GPRS BSS Dimensioning and Planning

The (E)GPRS dimensioning or planning activities (those are basically the same in(E)GPRS) are listed below:

Operators business plan investigation

Good understanding of current and future business plans (traffic figures withservice types) for creating the most suitable BSS plan or supports the operator toinvestigate the possible business scenarios for PSW services.

Operators BSS network structure audit (with core network)

Current and future network structure investigation of the hardware usage, softwareusage and capacity figures / limits.

Deployment plan preparation

The proper (E)GPRS BSS deployment plan is needed to find the way how thehighest (E)GPRS data rate with as less quality decrease as possible on CSW trafficcan be achieved.

Capacity calculations based on deployment plan

Available / required air interface capacity and network element connectivity

calculations (based on deployment plan analysis).

Parameter setting

Parameter set recommendation for network launch.

The Table 1 shows the flowchart of the (E)GPRS BSS network planning.


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Operators BusinessPlan Analysis

Operators BSSNetwork Analysis

Deployment PlanPreparation

Analysis of CapacityCalculation Results

BSS ParameterRecommendations

# of users with traffic

volumeServices with QoS

Controlled investment

Hardware audit

Software audit with features

Coverage and Interference

Deployment scenarios preparation basedon business plan and network audit

Air Interface Capacity

TSL data rate and multislotusage

Available and required capacity

TBF establishment

TBF flow

TBF release

Mobility

Connectivity Capacity

PCU Calculations

Gb, PAPU and SGSN calculations

Operators BusinessPlan Analysis

Operators BSSNetwork Analysis

Deployment PlanPreparation

Analysis of CapacityCalculation Results

BSS ParameterRecommendations

# of users with traffic

volumeServices with QoS


Hardware audit

Software audit with features

Coverage and Interference

Deployment scenarios preparation basedon business plan and network audit

Air Interface Capacity

TSL data rate and multislotusage

Available and required capacity

TBF establishment

TBF flow

TBF release

Mobility

Connectivity Capacity

PCU Calculations

Gb, PAPU and SGSN calculations

Table 1 (E)GPRS BSS network dimensioning and planning

The dimensioning and planning approach in this document is based on network with

existing GPRS functionality.

1.2 DSP Resource Management Issues in PCU2

The following link contains up to date information about PCU2 connectivity problems incase of e.g. territory upgrade if GPRS and EGPRS are multiplexed.


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2. OPERATORS BUSINESS PLAN

The business plan shows the importance level of (E)GPRS services.

The networks need different setup in case of e.g. background service requirement withoutguaranteed bit rate on selected BTSs only compared to the e.g. streaming requirement forthe whole network.

Therefore the network planning outcome should be in accordance with the business plan.

Usually the business plan requirements are mainly related to:

Number of users with traffic volume (with density map)

Services with QoS both on CSW and PSW


All the expectations above must be fulfilled to operate successful (E)GPRS services.

2.1 Number of Users with Traffic Volume

The number of users and the generated traffic by these users are needed to estimate thecapacity that must be provided by the network in the following months and years on celllevel (if it is possible).

2.2 Services with QoS both on CSW and PSW

The number of users with traffic figures gives the picture about traffic volume. But e.g. thebackground services can accept higher delay in the traffic flow, meanwhile e.g. thestreaming services are very sensitive for the delay and thus for the available capacity (withsignal level and C/I situation) in the radio network.

Therefore the investigation of traffic volume with QoS can show the exact requirements inplanning. If the traffic volume and/or the QoS policies need high amount of capacity (basedon the operators business plan), then the following steps should be taken into accountduring planning activities:

EGPRS should be preferred instead of GPRS and adequate separation between

EGPRS and GPRS users are needed

The layer with more available capacity should be preferred and the impact of CSWon PSW should be reduced

The layer with better signal level and C/I figures should be preferred

The EDAP, PCU and core (Gb, PAPU) capacity should be enough


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2.3 Controlled Investment

The list above in Chapter 2.2 does not contain one of the important inputs of planningactivities: the cost of the implementation of (E)GPRS.

The cost of hardware and software should be controlled enough to find the balancebetween implementation cost and quality of the services for having the investment withinthe limits.


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3. NETWORK AUDIT

The network audit is used to analyze network configuration with hardware installed,software releases, parameter setup, activated features and performance.

Both the hardware types and software / feature releases used by the operators must beanalyzed to stress the importance of limits in implementation.

The BSS audit can be based on the lists below:

BSS Hardware Considerations

o BSC types with PCU and PCU2

o BTS types (with Baseband units)

o TRX capability (mixture of GPRS and EGPRS TRXs)

GSM Feature Considerations

o MultiBCF and Common BCCH

o RF and BB Hopping

o FR/DR/HR and AMR

o IUO/IFH

(E)GPRS Feature Considerations

o PBCCH

o NMO1

o EPCR

o NCCR

o NACC

o Priority based QoS

o CS3-4

Coverage and Interference audit of the GSM network

o Coverage audit

o Interference audit

The analysis of the network just based on the list above gives the detailed picture of networkstructure, which can help to find the most appropriate way to deploy (E)GPRS and maximizethe data rate.

The following table shows the relations among features and SW/HW releases.


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FeaturesBSC SW

requirements PCU TypeBTS SW

requirements Mobile Release

PBCCH S10.5 onwardsPCU (not

supported byPCU2)

mobile dependent

EPCR S11 CD5 PCU/PCU2*US CX 4.0-4

onwardsR99 onwards

NCCR S11.5 PCU/PCU2R97 onwards(parameterdependent)

NACC S11.5 PCU/PCU2 R4

QoS S10.5 PCU/PCU2 independent

EQoS S13 PCU2 Rel3 R4

DTM S12 PCU Rel2 DTM capability

CS1-4 S11.5 PCU2 Rel1Metro, Ultra

C(M)X4.1 CD1Mobile dependent

Table 2 Relations between features and HW/SW releases

*PCU2 Rel1 and PCU2 Rel2 have the same hardware but different software.

The following subsections describe the network elements and features to be analyzed.


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3.1 Hardware Audit and Considerations

The hardware can be analyzed from connectivity limit and implementation restrictions pointof view.

3.1.1 BSC Types

BSC characteristics with S11.5 are described in Table 3 below:

BSC2i BSC3i BSC3i BSC3i BSC3i BSC3i BSC3i

Max BCSUs Working 8 2 3 4 5 6 7

BCSU_Spare 1 1 1 1 1 1 1

Max PCUs Working (logical) 16 4 8 12 16 20 24

PCUs_Spare (logical) 2 4 4 4 4 4 4

TRX_MAX 512 110 220 330 440 550 660

BTS_MAX 512 110 220 330 440 550 660

BCF_MAX 248 84 168 252 336 420 504

Table 3 BSC characteristics

With AS7-B HW maximum number of supported BCF objects is 248. Maximum number of504 BCF objects is supported with AS7-C HW.

BSC3i characteristics with S12 are described in Table 4 below:

BSC3i 1000 BSC3i 2000

Max BCSUs Working 10 10

BCSU_Spare 1 1

Max PCU-B Working (logical) 40 40

PCU-B_Spare (logical) 4 4

Max PCU2-D Working (logical) 100 100

PCU2-D_Spare (logical) 10 10

Max_RTLs 12800 25600

TRX_MAX 1000 2000

BTS_MAX 1000 2000

BCF_MAX 1000 2000

Table 4 BSC3i characteristics with S12 (BSC3i 1000/2000 with extension cabinet)


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3.1.2 PCU and PCU2

The first generation PCUs are optimized to meet GPRS requirements. The GPRSstandards of R97 concentrate on non real time solutions, which correspond to QoS classes"Background" and "Interactive" only.

The second generation PCUs (PCU2) has enhanced design architecture to optimally meetreal time requirements as well.

The later standards have introduced new real time QoS classes Streaming andConversational. Real time traffic has requirement for transfer delay, while non real timetraffic has not, therefore the traffic profile of typical real time application is very differentfrom typical non real time application.

S11.5 introduces the support for PCU2 (both PCU and PCU2 are supported by same SWpackage), but from BTS and SGSN perspective PCU2 is similar to PCU, it means that

PCU2 is backwards compatible.

PCU2 supports existing GPRS/EDGE functionality and there are no differences in EDAP orGb interfaces compared to PCU.

PCU2 units are equipped to BSC as existing PCU units, so PCU2 units can be installed toall existing BSC types (mixed configurations with PCU and PCU2 allowed)

The Nokia PCU product family consists of following products:

PCU Packet Control Unit, a general term for all NokiaGSM/EDGE PCU versions

General name Name of

HWproduct

variant

Explanat ion

Nokia First GenerationPacket Control Unit - PCU1

PCU First generation PCU for BSCE,BSC2E/A, BSCi and BSC2i

PCU-S First generation PCU for BSCE,BSC2E/A, BSCi and BSC2i

PCU-T First generation PCU for BSCE,BSC2E/A, BSCi and BSC2i

PCU-B First generation PCU for BSC3i,includes two logical PCUs

Nokia Second GenerationPacket Control Unit - PCU2

PCU2-U Second generation PCU for BSCE,BSC2E/A, BSCi and BSC2i

PCU2-D Second generation PCU for BSC3i,includes two logical PCUs

Table 5 PCU product family

In PCU1 plug-in unit theres 16 DSP cores. One PCU1 DSP core connects to up to 20 Abis16k sub TSLs. In PCU2 the number of DSP cores is 8. Each PCU2 DSP core can connectto up to 40 Abis 16k sub tsl. Max 32 of the 40 PCU2 DSP Abis 16k sub TSLs can carryGPRS or EGPRS master channels.

In PCU1 the 16 DSPs form two groups of 8 DSPs (even and odd numbered DSPs) that aresynchronized together via a serial bus between the DSP serial ports.


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PCU1 can share the same EDAP between several DSPs in the same synchronizationgroup, and one DSP can serve only one EDAP. The operator can optimize the PCU1

EDAP-DSP allocation by configuring the number of EDAPs per PCU1 to be 2, 4 or 8. Thenthe EDAPs are evenly distributed between the two DSP groups (which are similar sizes interm of Abis TSLs).

PCU2 can share the same EDAP between all the 8 DSPs. With PCU2 the recommendednumber of EDAPs is 1 to 8.

3.1.3 BTS Types

The (E)GPRS capability of TALK, UltraSite, PrimeSite, MetroSite and InSite is shown inTable 6:

TALK InSite** PrimeSite MetroSite UltraSite

GSM Ok Ok Ok Ok Ok

GPRS CS1 2 CS1 2 CS1 - 2 CS1 2* CS1-2*

EGPRS No No No MCS1-9 MCS1-9

*CS1-4 with PCU2**Insite is not supported by PCU2

Table 6 (E)GPRS capability of the BTS types

3.1.3.1 UltraSite Baseband Units

In UltraSite EDGE BTS, the EDGE RF unit (TSxB) always requires an EDGE capable baseband unit, BB2E or BB2F, even if it works in GSM mode only.

The EDGE base band unit (BB2E/F) is backwards-compatible and also supports the GSMRF unit, TSxA.

Base Band Unit and TRX type Functionality

BB2A + TSxA Ok

BB2A + TSxB Not Ok

BB2E + TSxA Ok

BB2E + TSxB Ok

BB2F + TSxA Ok

BB2F + TSxB Ok

Table 7 (E)GPRS baseband units and its interworking with GSM TRXs

The main driver behind BB2F is to provide an enhancement to the GSM/EDGE basebandunit (BB2E), which will enable mixed GSM and GSM/EDGE HW configurations within thesame hopping group in GMSK mode (mixed configuration hopping groups are restricted toGMSK calls only).


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The following figure (Table 8) shows the UltraSite with BB2A and BB2F with TSxA andTSxB, but in the example below with BTS SW CX3.3-1 mixed hopping groups can be

defined.

TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7

TSxA

TSxA

TSxB

TSxB

BB2A

BB2F

BCCH f1

f2

f3

f4

BCCH timeslot, does not hopBCCH timeslot, does not hop

Timeslot 0 ofTRXs2-4hop over MA (f2,f3,f4)


All timeslots 1-7 hop over MA (f1,f2,f3,f4)All timeslots 1-7 hop over MA (f1,f2,f3,f4)


BBBCCH f1

f2

f3

f4






TSxA

TSxA

TSxB

TSxB

BB2A

BB2F

BCCH f1

f2

f3

f4






BBBCCH f1

f2

f3

f4





Table 8 BB2A and BB2F with TSxA and TSxB

The BB2F is functioning with a minimum BTS SW level of CX3.3, but full BB hoppingfunctionality is not available until CX3.3-1.

Use of BB2F with earlier SW versions than CX3.3 will cause an unrecoverable error andthe unit will need to be returned to HWS for manual re-flashing. Therefore the unit is onlybeing shipped to those operators who have BTS SW CX3.3 installed in their network.

The following figure shows the UltraSite with BB2A and BB2E with TSxA and TSxB.

Base band hopping between TSxA and TSxB is not possible with BB2A/E combinations.The TSxB and BB2E units need to be configured in their own hopping groups, as shown inTable 9 below:


TSxA

TSxA

TSxB

TSxB

BB2A

BB2E

BCCH f1

f2

f3

f4


TSxA

TSxA

TSxB

TSxB

BB2A

BB2E

BCCH f1

f2

f3

f4


TSxA

TSxA

TSxB

TSxB

BB2A

BB2E

BCCH f1

f2

f3

f4


TSxA

TSxA

TSxB

TSxB

BB2A

BB2E

BCCH f1

f2

f3

f4


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Table 9 BB2A and BB2E with TSxA and TSxB

Separate hopping groups in the same sector are possible with Multi-BCF feature in

BSS10.5. If Multi-BCF is not used, BB2E/TSxB hopping group needs its own BCCH.

When EGPRS is activated in a base band hopping network, TSxBs has to be configured inseparate hopping groups than TSxAs. This can be achieved using the Multi-BCF feature.

3.1.4 TRX Capabilities

The following chapters describe the UltraSite, MetroSite and TALKFamily TRXs.

There can be both EGPRS capable and non-EGPRS capable TRX implemented in EGPRScapable BTS (physically in the same BTS).

If there is one EGPRS and one GPRS TRX in the cell, the GPRS TRX must have settingGTRX=N.

PREF parameter must be set to Yes on the EGPRS capable TRX (MBCCH), otherwise incase of fault situation the EGPRS capability will not recover to the EGPRS TRX and theoperator will not get any notification or alarm about that.

3.1.4.1 UltraSite TRX Capabilities

Frequency band TSxA TSxB

GSM 900 TSGA N/A

GSM 1800 TSDA N/A

GSM 1900 TSPA N/A

GSM/EDGE 800 N/A TSTB

GSM/EDGE 900 N/A TSGB

GSM/EDGE 1800 N/A TSDB

GSM/EDGE 1900 N/A TSPB

Table 10 UltraSite TRX capabilities


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3.1.4.2 MetroSite TRX Capabilities

Output power Frequency band Unit type Notes

5 W GSM 900 HVTG Standard filter

5 W GSM 900 HVTJ Customer specific filter J

5 W GSM 900 HVTH Customer specific filter H

5 W GSM 1800 HVTD Standard filter

5 W GSM 1900 HVTP Standard filter

5 W GSM/EDGE 800 WTFA Standard filter

10 W GSM/EDGE 900 CTGA Standard filter

10 W GSM/EDGE 900 CTGJ Customer specific filter J

10 W GSM/EDGE 900 CTGH Customer specific filter H

10 W GSM/EDGE 1800 CTDA Standard filter

5 W GSM/EDGE 1900 WTPA Standard filter

- - VTSA Transceiver shield unit

Table 11 MetroSite TRX capabilities

3.1.4.3 TALKFamily TRX Capabilities

TALKFAMILY TRXs are GPRS capable only. TRXA is for GSM 900, TRXD for GSM 1800,and TRXE for GSM 1900 applications. The Extended Cell feature for the GSM 900application requires TRXA 13 and the GSM 1800 application requires TRXD 12.


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3.2 GSM Feature Audit and Considerations

The limitation of the following GSM features must be taken into account.

3.2.1 MultiBCF and Common BCCH

The most important advantage of MultiBCF and CBCCH from (E)GPRS planning point ofview is that it can help to separate the GPRS and EGPRS territories from each other so theeffect of GPRS and EGPRS multiplexing on the same TSL can be reduced (in the worstcase PCU can allocate GPRS TBF to TSL used by EGPRS TBF).

The biggest disadvantage of MultiBCF and CBCCH in (E)GPRS implementation is the limitcoming from BB and RF hopping in S11 backward.

(E)GPRS territory must be configured into BCCH BTS in the segment with two or moreBTSs on the same bandif

o BTSs are using hopping

o PBCCH is not used

If hopping is not used, (E)GPRS territory can be configured to only non BCCH BTS, too

If PBCCH is used (with hopping), GPRS territory can be configured to only non BCCH BTS,too.

The GPRS territory must be defined to the BCCH frequency band in a Common BCCHsegment in which more than one frequency band is in use.

Otherwise the GPRS feature will not work properly in the cell. The reason for thisrequirement is that in cases when the MS RAC of the GPRS mobile is not known by thePCU, the TBF must be allocated on the BCCH frequency band first. During the first TBFallocation, the GPRS mobile indicates its frequency capability to the PCU. After that otherfrequency bands of the cell can be used for the GPRS mobile accordingly.

The reason behind the limitation described above is that the (E)GPRS mobile allocation ofSystem Information13 message is sent only to BCCH BTS because the segmentation ofImmediate Assignment message is not supported.

This is due to the fact that frequency parameters are encoded to the ImmediateAssignment on CCCH with indirect encoding. Without PBCCH, indirect encoding can onlyrefer to the System Information 13 message, which in Nokia BSS contains GPRS MobileAllocation only for the BCCH BTS.

The limitation to use only indirect encoding with hopping frequency parameters inImmediate Assignment comes from the fact that Immediate Assignment messagesegmentation is not supported in Nokia BSS.

The other two possible hopping frequency encodings, direct 1 and 2 encoding, might use alarge number of octets for the frequency hopping. Large sized frequency parameters causecontrol message segmentation, thus as Immediate Assignment segmentation is notsupported, direct 1 and 2 encoding cannot be used.

Therefore, TBFs must initially be allocated to the BCCH BTS. Later, the TBFs may bereallocated to other BTSs as well.


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So if baseband / frequency hopping and (E)GPRS are used in a cell without PBCCH, theoperator must configure the BCCH TRX to a (E)GPRS-capable BTS.

The limits above with hopping on CBCCH configuration will not be the problem with S11.5,so the BTS1 can have GPRS territory, while the BTS2 can have EGPRS territory. TheEGPRS TBF will be established firstly on BTS1 as a GPRS TBF and will be reallocated andestablished again on BTS2 as an EGPRS TBF even with hopping on both BTSs.

3.2.2 BB and RF Hopping

From functionality point of view the RR manager avoids the use of TSL0 for multi channelallocation in GPRS when base band hopping is used. However TSL0 is not avoided insingle slot allocation with BB hopping in the non-BCCH BTSs BTSs.

The initial reason for not choosing TSL0 for GPRS was that this timeslot was hopping overfewer frequencies and therefore had less hopping gain, this is no longer valid for non-

BCCH BTSs.

In case of RF hopping there are restrictions if MultiBCF/CBCCH is used with S11. Seesection 3.2.1 above.

From planning point of view the average interference level is depending on hopping.Therefore the TSL data rate can be increased on network level if hopping is used, since theC/I can be increased by BB and RF hopping.

3.2.3 Extended Cell

ETRX cannot carry (E)GPRS TCHs in extended cell, but NTRX is able to handle it.Extended Cell can be used only with the BTS software BTS 1063 Extended cell radius.

Extended Cell feature in UltraSite is available from S11.5 only.

3.2.4 FR/DR/HR

HR TCH cannot be allocated to (E)GPRS TSLs, but DR TSL can be used for (E)GPRS.

3.2.5 AMR

AMR network with a BCCH reuse of 9 gives the same performance as an EFR network withBCCH reuse of 12. This means that tighter BCCH reuse can be implemented with AMR.

However, one more fact needs to be considered. In the case AMR non-capable mobilecould suffer as well as (E)GPRS users. Thus, the percentage of the non-AMR capablemobiles (including roaming ones) as well as data usage performance (cell selection, re-selection, C/I on cell border etc.) shall be considered. Unless very high spectrum shortagecases, introduction of AMR does not justify tightening of BCCH.

The detailed description of AMR can be found in the following QP2 location:

http://qp2.connecting.nokia.com/QuickPlace/npcommunityqp/PageLibraryC2256FB8004C83E6.nsf/h_930E298B34D11351C2256FB80073D5D8/32251134F8837CBEC22570AE0053261D/?OpenDocument


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3.2.6 IUO/IFH

The (E)GPRS TCHs cannot be allocated to super layer, but the regular layer is able tocarry it.


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3.3 (E)GPRS Feature Audit and Considerations

The following features can be used for improving the (E)GPRS performance.

3.3.1 PBCCH

The advantage of PBCCH is the following:

o Separation of CSW and PSW signaling

If the TRXSIG is overloaded, a possible way of reduction is to separate PSWsignaling from CSW signaling, so the PSW signaling is not loading TRXSIG anymore.

o Separation of CSW and PSW users from neighboring point of view.

PSW and CSW users can have their own neighbor relations, so the PSW traffic canbe pushed to the required cell.

Disadvantage of PBCCH implementation are described below:

o The PBCCH capable terminals penetration is not high enough.

In case of PBCCH implementation the PSW signaling is conveyed on PBCCH only.The non PBCCH capable (E)GPRS terminals are not able to read PBCCH so theywill exclude from the PSW data services.

o One TCH is occupied by PBCCH

Less capacity is available for user traffic.

PCU2 Rel-1 does not support PBCCH. PBCCH is E6 (removal) candidate for S13.

3.3.2 NMO1

With Network Mode of Operation 1 (NMO1) CS-voice paging is conveyed on the samechannel as used by packet-switched services (CCCH, PCCCH or data channel).

Therefore mobiles need to monitor only one paging channel. SGSN suspends data sending

for the duration of CS paging coming on packet data channel, because of the Gs-interfaceco-ordination between MSC and SGSN.

The usage of NMO1 offers better performance, lowest idle power consumption, lowestBLER (bock error rate) and minimizes the paging load in the network.

CS calls and CS pagings will go via Gb only to those subscribers that are GPRS attached.

GPRS attach triggers the combined location update and routing area update which in turncreates an association in the MSC so that incoming CS calls and pagings can be routed viaGPRS channels and Gb.


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Those subscribers that not attached will still be CS paged in the normal CS signalingchannels and SS7 link between BSC and MSC.

Disadvantage of NMO1 is described below:

o Minimum one dedicated timeslot is a must with NMO1 to guarantee that GPRSattached subscribers can be paged at all and that their routing updates will bereceived by network

o If signaling and traffic channels are congested in PSW territory, no paging norRA/LA updates will go through and mobile is lost by network!

MSC M12 feature candidate: MSC/VLR has to repeat the paging via A interface when thedestination point is not available, i.e. if any of the signaling links (Gs, Gd, Gb) or SGSN isdown.

3.3.3 EPCR

EGPRS Packet Channel Request (EPCR) is always on when BSS 11 is used (S11 CD5.0)and supported by MS Rel99 onwards. (UltraSite supports EPCR (CX4.0-x) and EDGEsupport is required, too.)

One TS is allocated when (E)GPRS one phase access is used on CCCH, so thereallocation need for getting more TSLs is checked when establishment is completed.

The Packet Resource Request with EPCR is implemented with one phase access;therefore the TBF establishment will be sent faster than in two phase access.

The detailed information related to EPCR is available in [1].

3.3.4 NCCR

The Network Controlled Cell Reselection (NCCR) is a resource allocation related feature.The target is to allocate the GPRS and EGPRS users to the most appropriate cells, wherethe highest data throughput can be provided.

The detailed information related to NCCR is available in [1].

3.3.5 NACC

NACC specifies procedures for network to send target cell system information prior toactual cell change. This reduces the data transmission break time during the cell changeprocedure.

The detailed information related to NACC is available in [1].

3.3.6 QoS

With the Priority Based QoS in BSC the operator can assign different priorities to he users.The PCU scheduling algorithm will make use of the priority information in the schedulingprocess. The service experienced (QoE) by high priority users and low priority users aredifferent from each other.

The detailed information related to QoS is available in [1].


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3.3.7 EQoS

Enhanced Quality of Service (EQoS) presents in S13 a set of enhancements that enablesupport of services that require guaranteed bit rate. EQoS introduces support for StreamingTraffic Class in addition to the already supported Background and Interactive TrafficClasses in S10.5 and S11.

The detailed information related to QoS is available in [1].

3.3.8 GPRS CS1-4

In PCU2 the GPRS CS1 - CS4 coding schemes are supported. There is a new LinkAdaptation algorithm was developed in the PCU2 to handle all the coding schemes.

The detailed information related to CS1-CS4 is available in [1].

3.3.9 DA with USF4

The Dynamic Allocation on UL with USF4 is described below:

On DL 4 TSLs are used by 8-PSK modulation (TSL 4-7), but now TSL 7 is GMSKmodulated, because of USF is pointed to GPRS MS (request for UL transmission on TSL7))

0 1 2 3 4 5 6 7

Round 1 USF

Round 2

Round 3

...

... USF

...

On DL 4 TSLs are used by 8-PSK modulation (TSL 4-7), but now TSL 7 is GMSKmodulated, because of USF is pointed to GPRS MS (request for UL transmission on TSL 6and 7))

0 1 2 3 4 5 6 7

Round 1 USF USF

Round 2

Round 3

...

... USF USF

...

3.3.10 EDA

Extended Dynamic Allocation functionality on UL is shown below:

On DL 4 TSLs are used by 8-PSK modulation (TSL 4-7), but now TSL 7 is GMSKmodulated, because of USF is pointed to GPRS MS (request for UL transmission on TSL7))


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0 1 2 3 4 5 6 7

Round 1 USFRound 2 USF

Round 3 USF

... USF

... USF

...

On DL 4 TSLs are used by 8-PSK modulation (TSL 4-7), but now TSL 7 is GMSKmodulated, because of USF is pointed to GPRS MS (request for UL transmission onTSL 4, 5, 6 and 7), but EDA is used)

0 1 2 3 4 5 6 7

Round 1 USFRound 2 USF

Round 3 USF

... USF

... USF

...

*If max 2 TSLs are needed on UL for GMSK MS, Dynamic Allocation (DA) will be used withUSF4.

3.3.11 HMC

High Multislot Classes (HMC) increases GPRS/EDGE peak downlink throughput to 296

kbit/s.

3GPP release 4 or earlier MSs are limited to combined downlink and uplink timeslot sum of5. 3GPP release 5 (TS 45.002) introduces new MS multislot classes which allow sum ofdownlink and uplink timeslots of 6.

New maximum allocation configurations:

Downlink + uplink: 5+1 and 4+2

Downlink + uplink: 3+3 and 2+4 (With Extended Dynamic Allocation ApplicationSoftware)

3.3.12 DTM

Dual transfer mode is providing simultaneous circuit switched voice and Packet Switcheddata service in a coordinated manner.

In dual transfer mode, the mobile station is simultaneously in dedicated mode and in packettransfer mode so that the timeslots allocated in each direction are contiguous and within thesame frequency.

The CS part consists of a single slot connection, while the PS part can consist of a multislotconnection.

Entering to DTM mode goes through the dedicated mode:


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PS radio connection has to be released when entering and leaving Dual TransferMode

Nokia solution minimizes the outage on downlink data transmission

3GPP release 6 allows transitions between PS and DTM (BSS13 candidate)

Dual TransferMode

Packet TransferMode

RR Idle Mode/Packet Idle Mode

PS Release

CS Release

DTMAssignment

CS SpeechConnection

PS DataConnection

CS Speech+PS Data

Connection

DedicatedMode

DedicatedMode

Table 12 DTM state transitions

More information is available in the following link:

http://qp2.connecting.nokia.com/QuickPlace/npcommunityqp/PageLibraryC2256FB8004C916E.nsf/h_600CA9EF1F0B129BC2256FB800770216/EA51D79F0CA07F21C22572120036CDE3/?OpenDocument


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3.4 Coverage and Interference Audit Air Interface

The coverage and interference must be analyzed, because the TSL data rate is defined bycoverage and interference as well.

3.4.1 Signal Level Estimation

The average signal level of a cell/segment must be estimated for calculating the TSL datarate based on sensitivity.

The signal level estimation can be based on

Planning tool plots

Drive test measurements

OSS measurements

3.4.1.1 Planning Tool Calculations

The average GSM signal level of an area (cell, BTS, BSC, etc) can be estimated just basedon NetAct coverage plots.

An example of planning tool plot can be seen in Table 13below:

Table 13 GSM signal level (with indoor 95 % location probability)

The figure above shows the outdoor coverage situation. The red color means signal levelwith better than 85 dBm, orange color means threshold between 85 and 95 dBm andthe yellow means less than 95 dBm signal level.


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The NetAct is able to calculate the size (territory) of the different signal levels. So on theexample above the 59% of the area is covered by higher than 85 dBm therefore the TSL

data rate is around 50 kbps because of high enough signal level (the data rate estimation isbased on Table 16 without interference).

The 21 percent of the are is covered between 85 and 95 dBm so the average TSL datarate is around 40 kbps, while the 20 % of the area is covered with less than 95 dBm,where the TSL data rate is approximately 30 kbps.

3.4.1.2 Drive Test Measurements

The following measurement shows drive test results, which can help to estimate theaverage signal, level of the measured area.

Table 14 Signal level measurement from Nemo TOM


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3.4.1.3 OSS Measurements

The following table shows the signal level situation collected by Network Doctor report 204.

RX lev UL UL UL UL UL UL UL UL UL

range q0 q1 q2 q3 q4 q5 q6 q7 share in range

(dBm) (%) (%) (%) (%) (%) (%) (%) (%) (%)

------ ------- ------- ------- ------- ------- ------- ------- ------- -------

-100 1.28 0.42 0.47 0.51 0.56 0.46 0.39 0.27 4.35

-95 4.09 0.64 0.61 0.52 0.39 0.2 0.11 0.01 6.57

-90 8.97 0.74 0.63 0.48 0.32 0.14 0.07 0.01 11.36

-80 44.59 1.14 0.88 0.61 0.3 0.13 0.07 0.01 47.73

-70 24.81 0.27 0.22 0.17 0.07 0.03 0.03 0 25.61

-47 4.27 0.03 0.03 0.02 0.01 0.01 0 0 4.37

------- ------- ------- ------- ------- ------- ------- ------- -------

sum 88.01 3.24 2.84 2.32 1.65 0.97 0.67 0.31 100

RX lev DL DL DL DL DL DL DL DL DLrange q0 q1 q2 q3 q4 q5 q6 q7 share in range

(dBm) (%) (%) (%) (%) (%) (%) (%) (%) (%)

------ ------- ------- ------- ------- ------- ------- ------- ------- -------

-100 0.3 0.06 0.08 0.1 0.13 0.15 0.11 0.04 0.98

-95 0.77 0.15 0.17 0.2 0.17 0.1 0.04 0.01 1.6

-90 2.7 0.31 0.31 0.3 0.21 0.12 0.05 0.01 4.01

-80 17.87 1.19 1.09 1.02 0.66 0.34 0.14 0.03 22.35

-70 42.84 1.89 1.63 1.32 0.69 0.3 0.12 0.03 48.82

-47 19.96 0.69 0.59 0.48 0.26 0.12 0.1 0.04 22.24

------- ------- ------- ------- ------- ------- ------- ------- -------

sum 84.44 4.29 3.87 3.44 2.12 1.12 0.55 0.16 100

Table 15 ND 204 quality / level distribution

As it can be seen from the table above most of the measurement results are from betterthan 90 dBm and from quality 0-2.

3.4.1.4 GPRS

The GPRS RLC/MAC data rate dependency on signal level will be figured out later on inthe next version of this document.

3.4.1.5 EGPRS

The next figure shows the EGPRS RLC/MAC data rate dependency on signal level.


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RLC/MAC Data Rate (2 TSLs)

0

20

40

60

80

100

120

-74 -76 -78 -80 -82 -84 -86 -88 -90 -92 -94 -96 -98 -100 -102 -104

RxLev (dBm)

kbps

RLC/MAC Data Rate (2M Download on 2 TSLs)

Table 16 Signal level vs. RLC/MAC data rate

So the TSL data rate can be estimated if the average signal level is know for cell/segments.

3.4.2 Interference Dependency

The following subsections show the interference dependency in GPRS and EGPRS.

3.4.2.1 GPRS

The GPRS RLC/MAC data rate dependency on C/I will be figured out later on in the nextversion of this document.

3.4.2.2 EGPRS

The next figure shows the EGPRS RLC/MAC data rate dependency on C/I


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C/I dependency (FTP Download on 2 TSLs)

0

20

40

60

80

100

120

36 34 32 30 28 26 24 22 20 18 16 15 14 13 12 11 10 9

C/I

kbps

RLC/MAC Data Rate (2M Download 2TSLs)

Table 17 C/I vs. RLC/MAC data rate

3.4.3 TSL Data Rate Dependency on GSM Functionality

In case of TSL data rate estimation the mixture of signal level and C/I dependency must betaken into account. The following figure can help to estimate the TSL data rate.

RLC/MAC Data Rate (FTP Download on 2 TSLs)

0

20

40

60

80

100

120

-65 -70 -75 -80 -85 -90 -95 -100 -105

Signal level (dBm)

kbps

No Interference

C/I 25 dB

C/I 20 dB

C/I 15 dB

Table 18 TSL data rate vs. signal level and interference


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3.5 Abis Signaling Audit TRXSIG

Many of the customers end-user service is generating new load to existing network. Alsothe load profile has been changed due to the changes of the end user behavior comparedto the days the network was dimensioned. The signaling load might also have beenincreased in a given signaling link due to a recent BSS feature activation in the BSSnetwork.

To ensure that the A-bis signaling links are able to carry the increased signaling traffic it isrecommended to offer the A-bis signaling optimization service, whenever either the radionetwork is optimized or an upper level end-user service is optimized. Non-optimized A-bissignaling could easily be the bottleneck in achieving the target performance level.

In addition to A-bis signaling link optimization service the physical layer transmission qualityaudits could be considered as an offered service module as the physical layer is thefoundation for the whole A-bis respectively.

The detailed information related to TRXSIG is available in [1]and [2].

3.6 EDAP Audit

The number of EDAP TLSs (DAP size) connected to one BCF can be a hard limiting factor,if there are more than one EGPRS users with 4 TSLs and MCS. So the aim of audit is toobserve the DAP size or plan DAP size enough based on radio TSL usage (amount andMCSs).

More information and the EDAP planning tool can be found in [3].

3.7 PCU Audit

In case of PCU audit the connectivity limits must be taken into account. The limits aredescribed in Section 3.1.2.

BCS2i can have 8 x 2 (+ 2 for redundancy) physical PCU units altogether, while BSC3icapacity is 6 x 4 (+2 for redundancy) PCUs in full configuration up to S11.5

S12 can have 5 PCUs per BCSU.

3.8 Conclusion on BSS Network Audit

After auditing the network the network planning engineer is aware of the hardware,software, feature as well as signaling (TRXSIG, BCSU), interface (air interface, EDAP) andnetwork element connectivity (E1 (EDAP), PCU) functionality and limitations.


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3.9 Gb and SGSN (SG6) Audit

The following chapters describe the audit of Gb interface links and SGSN with PAPUs.

3.9.1 Gb Interface

31 Gb 64 kbps links can be connected to one PCU and 512 Gb links can be connected toone PAPU. The amount of links between PCU and PAPU can be a hard limiting factor, sobetter to have far enough capacity on Gb, but on the other side, too much Gb links willrequire too many PAPUs as well.

The Gb interface capacity can be modified in two ways either by modifying theCommitted Information Rate (CIR) or the Bearer Channel Access Rate.

So the NS-VC's CIR can be increased if there is sufficient room on the bearer channel thatthe NS-VC is using.

If the Bearer Channel Access Rate is increased, the CIR of the NS-VCs using the bearerchannel must be increased before the Gb interface capacity is increased.

If IP transport is used in the Gb interface, it is not possible to modify the capacity of the Gbinterface.

3.9.2 SGSN and PAPU

The user capacity of SGSN and PAPUs are listed below:

SG4 PAPU with High Capacity PAPU (HCPAPU) has a capacity up to 60,000attached subscribers, but 2G-SGSN capacity remains at 320,000 subscribers. So

this feature aims at serving for non-uniform distribution of subscribers on thedifferent PAPUs.

SG6 PAPU has a capacity of 100,000 attached subscribers, i.e. a total of 1,600,000per 2G-SGSN.

In SGSN audit the PCU RA / PAPU mapping, the number of subscribers and the PAPUload must be analyzed.

Due to the fact that many of the dimensioning aspects are directly related to thecombination of HW and SW release in question, which could have several possibilities, thefollowing links provide the product line portals to the relevant product documentation.

SG6http://www10.connecting.nokia.com/net/sgsnintranet.nsf/document/ES5166EJ6Z?OpenDocument

SG5.1http://www10.connecting.nokia.com/net/sgsnintranet.nsf/document/ES516JKGVX?OpenDocument

SG5http://www10.connecting.nokia.com/net/sgsnintranet.nsf/document/ES5166EJ49?OpenDocument


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4. DEPLOYMENT PLAN

The deployment plan is needed to analyze the different cell/segment options based on theexisting networks structure.

The aim of the analysis of cell/segment options is to find the most appropriate deploymentscenarios, where:

The TSL data rate (RLC/MAC) and multislot usage as high as possible

The impact of PSW services on CSW services (and vice versa) as low as possible

All the hardware and software considerations are taken into account

The level of investment can be estimated

The deployment plan is a bit different if cells or segments are used. The following chapterscontain the description of deployment option creations for cell and segment environment.

The following steps are recommended for creating and analyzing deployment scenarios:

1. Hardware and software considerations

2. Signaling channel configuration and capacity

3. CDEF location (BCCH or non BCCH TRX)(TSL data rate and multislot usagemaximization)

4. CDEF size definition (multislot usage on air interface and connectivity in PCU)

5. Required CDED (because of NMOI or other throughput requirements on BTS level)

6. GTRX, GENA and EGENA parameter setup

4.1 Deployment Planning Steps for Cells

The following subsections show the way how the different deployment scenarios areanalyzed step by step.

4.1.1 Hardware and Software Considerations

BSC and PCU type (CS1-2 or CS1-4)

The BSC type shows the number and type of physical and logical PCU that can beused in the BSC. (Refer to 3.1.1.)

The PCU types show the connectivity figures of PCU variants. (Refer to 3.1.2.)

BTS and TRX type (GPRS or (E)GPRS capability)

The BTS types show the GPRS and EGPRS capability of the BTS. (Refer to 3.1.3)If there is EDGE and non-EDGE TRX in the BTS, the non-EDGE TRX must havesetting GTRX=N.


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The PREF parameter on the EDGE capable TRX must be set to P (preferred),otherwise after fault situation the EDGE capability will not recover to the EDGE TRX

and the operator wont get any notification or alarm about this.

BB card type and TRX variants in UltraSite

If Base Band hopping is used, the following points must be taken into account:

o Base band hopping between TSxA and TSxB is not possible with BB2A/Ecombinations. The TSxB and BB2E units need to be configured in their ownhopping groups, which requires SEGMENT solution, (Refer to Chapter3.1.3.1)

o Mixed TRX (TSxA and TSxB) configuration is possible with BB2F only, butthe modulation will be limited to GMSK (Refer to Chapter 3.1.3.1)

4.1.2 Signaling

If the signaling has combined structure and occupies the TSL0 only (e.g. Broadcastchannels + Common control channels + SDCCH/4 + SACCH/4), then the combinedstructure can lead to congested air interface signaling, so the signaling traffic (RACH,AGCH, PCH, SDCCH) must be analyzed in deployment planning for avoiding signalingcongestion. Dynamic SDCCH feature can be used to increase SDCCH capacity if needed.

If the signaling has uncombined structure and occupies the TSL0 and TSL1, then theSDCCH has probably enough capacity for RA/LA cell-reselection if NMO1 is notimplemented.

DR TSL configuration can lead to heavy signaling as well.

The SDCCH TSL is reducing the available capacity for both CSW and PSW user traffic onBCCH TRX.

4.1.3 CDEF Location (BCCH or non BCCH TRX)

From available capacity point of view the preferred TRX should be that one, which gives:

o As good signal level and C/I as possible for maximized TSL data rate

o More available capacity for as good multislot usage as possible

More time slots available for (E)GPRS traffic without more hardware, if AMR or HR

are implemented (the drawback is a slight decrease in the speech quality usingAMR half rate when compared to AMR full rate in very bad C/I environment).

4.1.4 CDEF Size Definition

The CDEF size recommendation is 4 RTSL for serving the 4 TSL DL capable terminalswithout territory upgrade.

The CDEF size must be planned carefully, because the # of PCUs is heavily depending onCDEF size as well.


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4.1.5 CDED Size Definition

One RTSL CDED size is recommended, because of NMOI or other throughputrequirements on BTS level (like QoS).

4.1.6 GTRX, GENA and EGENA Parameter Setup

These parameters are used to define the PSW capability on TRX (GTRX), GPRS capabilityon BTS (GENA) and EGPRS capability on BTS level (EGENA).

If GPRS and EGPRS capable TRXs are used in one BTS (mixed configuration), then forproper GTRX setting pls. refer to Chapter 4.1.1.

4.2 Deployment Planning Steps for Segments (MultiBCF/CBCCH)

The following subsections show the way how the different deployment scenarios forsegments are analyzed step by step.

4.2.1 Hardware and Software Considerations

Refer to Chapter 4.1.1.

4.2.2 Signaling


4.2.3 BTS Selection to Separate GPRS and EGPRS (and CSW)

The creation of Segment may need to separate GPRS traffic from EGPRS traffic. HoweverUSF4 is implemented in PCU2 Rel. 1, the separation of GPRS and EGPRS among BTSsstill recommended.

Those BTSs should be chosen for PSW traffic, where the available capacity, signal levelconditions and C/I ratio is as good as possible.

Segment concept is also useful, if one of the BTSs in Segment is used for GPRS with CS1-2 without EDAP pool creation.

If the same BTS in Segment is used both for GPRS and EGPRS, then the deployment

strategy steps for cells can be used. (Refer to Chapter 4.1)

The segment concept can be used to push the CSW traffic to the most appropriate BTSs,so the impact of PSW traffic on CSW and vice versa can be reduced.

4.2.4 CDEF Location (BCCH or non BCCH TRX)



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4.2.5 CDEF Size Definition

The CDEF size recommendation is 4 RTSL for serving the 4 TSL DL capable terminalwithout territory upgrade.

The CDEF size must be planned carefully, because the # of PCUs are heavily dependingon CDEF size as well.

4.2.6 CDED Size Definition

One RTSL CDED size is recommended, because of NMOI or other throughputrequirements on BTS level (like QoS).

4.2.7 GTRX, GENA and EGENA Parameter Setup



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4.3 Cell Option Example

The deployment considerations of the following cell option are described below:

Layer strategy BTSs T RXs T SL0 TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7 PSW terr.

TRX1 BCCH SDCCH TCH/D TCH/D TCH/D TCH/D TCH/D TCH/D

TRX2 T CH/F TCH/F TCH/F TCH/ F TCH/F TCH/F TCH/F TCH/F

TRX3 T CH/F TCH/F TCH/F TCH/ F TCH/F TCH/F TCH/F TCH/F

TRX4 TCH/F TCH/F TCH/F TCH/F Default Default Default Dedicated (E)GPRS

Cell option BTS1CSW, (E)GPRSLayer1

Table 19 Cell Option Example

Layer strategy

The Cell Option Example has one cell without MultiBCF / CBCCH.

GPRS and EGPRS have the same territory on TRX4 with 4 TSLs.

GPRS and EGPRS have the same territory; therefore the possibility of GPRS-EGPRS multiplexing is high in case of high CSW and PSW traffic.

There is dedicated territory for providing PSW services even in high CSW traffic,too.

NMO1 can be implemented, because of dedicated territory.

4.3.1 Cell Option Example Description

Hardware and Software considerations

o If the TRXs are mixed (TSxA and TSxB), the non EDGE capable TRXs musthave GTRX set to N and the TSxB must be preferred by set the PREFparameter to P.

o If BB hopping is used, mixed TRXs can be implemented with BB2F baseband unit, but the modulation will be limited to GMSK.

o In case of BB2E, segment option is the only way to use GPRS and EGPRSwith BB hopping. The following table shows a possible solution for segmentimplementation and GPRS / EGPRS separation.

Layer strategy BTSs TRXs TSL0 TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7TRX1 CBCCH SDCCH TCH/D TCH/D TCH/D TCH/D TCH/D TCH/D

TRX2 TCH/F TCH/F TCH/F TCH/F Defau lt Defau lt Defaul t Dedicated (E)GPRS

TRX3 TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F


Segment option

Layer1 CSW, (E)GPRS

CSW onlyLayer2

BTS1

BTS2

Table 20 Segment option example if BB hopping is used with TSxA and TSxB and BB2E

For more information pls. refer to Chapter 4.1.1.


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Signaling

o

The signaling has uncombined structure and occupies the TSL0 and TSL1.The SDCCH has probably enough capacity for RA/LA cell-reselection if evenNMO1 is not implemented.

o The SDCCH TSL is reducing the available capacity for both CSW and PSWuser traffic.

o TRX1 has TCH/D TSLs, which can lead to heavy signaling

CDEF Location

Default territory is located on 4thTRX. The CSW TSLs in this TRX are TCH/F, which

is loaded firstly compared to TCH/D by resource management, but there are otherTRXs with TCH/F, so probably it is not a limiting factor.

On the other side more time slots available for (E)GPRS traffic without morehardware, if DR and/or AMR are implemented. Dual rate and AMR TSLs can beused for (E)GPRS purposes, but HR is not.

The CDEF location must be analyzed by C/I point of view. Usually the BCCH layerhas better reuse, thus better C/I, but the available resource is limited, because ofsignaling channels. The lack of DL Power Control generates additional interference,so from this point of view the BCCH TRX is recommended.

GPRS and EGPRS have the same territory on TRX4, therefore in case of

multiplexing the reduction of EGPRS data rate is possible (because of USF pointedto GPRS UL user on EGPRS TBF).

With PCU2 the USF4 reduces the impact of multiplexing.

The reduction is depending on the penetration of GPRS and EGPRS users.

CDEF size

The (E)GPRS territory is 4 TSL, therefore the four TSL DL capable terminals canhave full DL capability on air interface without territory upgrade.

CDED size

There is dedicated territory for providing min. 1 PSW TSL even in case of highCSW traffic (a kind of QoS can be provided) and NMO1 can be implemented.

GTRX, GENA and EGENA

The TRX4 must have GTRX=Y, GENA=Y, EGENA=Y. In case of BB hopping, referto Chapter 4.1.1.


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4.4 Segment Option Example

The deployment considerations of the following cell option are described below:

Layer strategy BTSs TRXs TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7 TSL8 PSW terr.

TRX1 CBCCH SDCCH TCH/F TCH/F Default Default Default Dedicated EGPRS

TRX2 TCH/D TCH/D TCH/D TCH/D TCH/D TCH/D TCH/D TCH/D


TRX4 TCH/F TCH/F TCH/F TCH/F Default Default Default Dedicated GPRS

Segment option

Layer1 CSW, EGPRS BTS1

Layer2 CSW, GPRS BTS2

Table 21 Segment Option Example

Layer strategy

The Segment Option Example has segment configuration.

GPRS and EGPRS have separated territory (EGPRS on BTS1 while GPRS onBTS2); therefore the possibility of GPRS-EGPRS multiplexing is reduced.

Both layers have 4 TSLs territory for 4 TSL DL capable terminals.

The EGPRS territory is allocated to TRX1. It is useful if the signaling TRX hasbetter reuse, whereby probably better C/I.

There is dedicated territory for providing PSW services even in high CSW traffic,too.

NMO1 can be implemented, because of dedicated territory.

4.4.1 Segment Option Example Description

Hardware and Software Considerations

o If the first layer is Ultra site with TSxB, then (E)GPRS can be used even withBB hopping.

o If the first layer is Ultra site with mixture of TSxA and TSxB, then pls. refer toChapter 4.3.1.

o If the second layer is Talk family, then GPRS only service will be providedwithout EDAP (CS1-2).

o If the second layer is Ultra site with TSxA only and EGENA is set to No,then GPRS service (CS1-2) will be provided without EDAP.

The following table shows that kind of configuration, where the second layer iswith GPRS CS1-2 without EDAP.

Layer strategy BTSs TRXs TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7 TSL8 PSW terr.

TRX1 CBCCH SDCCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F (E)GPRS

TRX2 TCH/F TCH/F TCH/F TCH/F Default Default Default Dedicated


TRX4 TCH/F TCH/F TCH/F TCH/F Default Default Default Dedicated GPRS (CS1-2)

Segment option

Layer1 CSW, (E)GPRS BTS1

Layer2 CSW, GPRS BTS2

Table 22 Segment configuration with GPRS (CS1-2) on second layer without EDAP


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Signaling

The signaling has uncombined structure and occupies the TSL0 andTSL1. The SDCCH has enough capacity for RA/LA cell-reselection if evenNMO1 is not implemented.

The SDCCH TSL is reducing the available capacity for user traffic.

CDEF Location

The CSW traffic should be moved from TRX1, because the limitedresources for CSW. TRX1 has only two TCH/F TSLs.

The CDEF location must be analyzed from C/I point of view. Usually theBCCH layer has better reuse, thus better C/I, but the available resource islimited, because of signaling channels. The lack of DL Power Controlgenerates additional interference, so from this point of view the BCCHTRX is recommended.

Layer1 has EGPRS territory (EGENA = Y) with four TSLs.

Layer2 has GPRS territory with 4 TSLs, so the 4 TSL DL capableterminals can use 4 TSLs from the beginning without territory upgrade.

The multiplexing is still possible in case of high PSW and CSW traffic, butthe possibility is reduced.

CDED size

There is dedicated territory for providing min. 1 PSW TSL even in case ofhigh CSW traffic (a kind of QoS can be provided) and NMO1 can beimplemented.

GTRX, GENA and EGENA

The TRX1 must have GTRX=Y, GENA=Y, EGENA=Y, while TRX4 must haveGTRX=Y, GENA=Y, EGENA=N. In case of BB hopping on Ultra site, pls. refer toChapter 4.1.1.


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5. CONNECTIVITY CAPACITY DIMENSIONING

5.1 Introduction

The aim of the BSS Connectivity Capacity example is to show the calculation method, howthe CDEF, DAP size, the number of PCU and Gb link size can be dimensioned.

The dimensioning is not based on detailed network audit with all the configuration,parameter and feature information (like BSC types, # of available PCUs, LA/RA borders,etc), but on few data about # of BCFs, BTSs and TRXs with traffic volume assumption ofexisting CSW traffic and requirements on PSW data rate (if there is any).

The dimensioning example in this document is using PCU1 variant. The dimensioningprinciple applies both for PCU1 and PCU2 and any variant as far the variant specific data isused.

This dimensioning example assumes that RF dimensioning is done and thus bit rate perradio time slot has already been defined as shown in the Table 23.

RF ConnectivityBit rate per

RTSLRF Connectivity

Bit rate perRTSL

Table 23 EGPRS Dimensioning phases

The outcomes of the dimensioning task are size of CDED, CDEF, EDAP and Gb link andthe number of PCU units needed to handle the resources. When the BSC variant and BSCSW level is know the number of physical PCU plug in units can be defined. This example islimited to number of logical PCUs.

In this example first the CDEF and CDED are defined. Then EDAP size based on theCDEF and Gb link size base on EDAP size. This example illustrates two different scenariosfor PCU dimensioning. The first scenario is pure dimensioning without mapping EDAPs toPCU. This scenario is the simple and clear and involves less calculations. In this scenariothe PCU utilization (U) 70% is used. Higher utilization value may decrease the accuracy of

the dimensioning.

The other scenario is to do some planning steps to ensure that the given configuration canbe handled by the PCU. This scenario needs more calculations and thus gives moreaccurate results. In this scenario the PCU utilization may vary from 60% to 80% onconfiguration bases.


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5.2 Dimensioning Inputs

The aim of the dimensioning is to calculate the CDEFs, DAP sizes, the number of PCUsand Gb link sizes needed for EDGE/GPRS implementation on top of existing CSW voice.

The following inputs are used in the calculation example below:

One BSC with 40 BCFs

3 BTSs per BCF

Site configurations & amounts (see Table 24 below)

2+2+2 25 BCFs surrounding area, light blue colored Configuration 1

4+4+4 15 BCFs central area, deep blue colored - Configuration 2

Table 24 Site configuration and amount

BCF voice traffic

2+2+2 site on average has traffic of 8 Erl per BTS

4+4+4 site on average has traffic of 18 Erl per BTS

Blocking criteria 2%

Data traffic

Streaming user support requirement per BTS ~ 50 kbit/s

Average data throughput per BTS (by operator)

Central area - 200 kbit/s

Surrounding area 100 kbit/s


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Other considerations

Average MS multislot support in network 4 TSL

All BTSs and TRXs EDGE capable

Gb implementation planned as Frame Relay

Note in this example it is assumed that all BTSs in site/BCF have similar traffic profile tosimplify example. In addition it is assumed that data traffic need for 4+4+4 configuration ishigher than with 2+2+2 configuration. In some of 2+2+2 configurations could have higherdata traffic and need for higher data capacity than 4+4+4 sectors.

Note 2 It is assumed that given data amount per BTS is not needed to be supportedsimultaneously in all BTSs. This information is used for EDAP and Gb link dimensioning.


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5.3 Air Interface Capacity

5.3.1 Configuration before (E)GPRS

The following figures show the TRX configurations:

TSL0 TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7

BCCH MBCCH SDCCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F

TCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F

Table 25 2+2+2 configuration

Two RTSLs are reserved for uncombined signaling (BCCH and SDCCH), while the rest ofthe RTSLs are full rate RTSLs (no DR/HR implemented).

TSL0 TSL1 TSL2 TSL3 TSL4 TSL5 TSL6 TSL7

BCCH MBCCH SDCCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/FTCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F

TCH SDCCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F

TCH TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F TCH/F

Table 26 4+4+4 configuration

In case of 4+4+4 configuration there are three RTSLs are used as signaling (one BCCHand two SDCCH), the rest of the RTSLs are full rate RTSLs (no DR/HR implemented).

Each BCF (independently from the config type) have own E1 for transmission.

0 0

1 TCH0 TCH1 TCH2 TCH3 1 TCH0 TCH1 TCH2 TCH3




5 TCH0 TCH1 TCH2 TCH3 5 TCH0 TCH1 TCH2 TCH36 TCH4 TCH5 TCH6 TCH7 6 TCH4 TCH5 TCH6 TCH7







13 TRXSIG1 TRXSIG2 13 TCH0 TCH1 TCH2 TCH3



16 BCFSIG 16 TCH4 TCH5 TCH6 TCH7

17 17 TCH0 TCH1 TCH2 TCH3








25 2526 26

27 27 TRXSIG1 TRXSIG2 TRXSIG3 TRXSIG4

28 28 TRXSIG5 TRXSIG6 TRXSIG7 TRXSIG8

29 29 TRXSIG9 TRXSIG10TRXSIG11 TRXSIG12

30 30 BCFSIG

31 31Q1-management Q1-management

Table 27 E1 setup for 2+2+2 and 4+4+4 configuration


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5.3.2 (E)PRS Deployment Scenarios

All the TRXs have GPRS and EGPRS capability, so the following parameter setup is used:

TRX: GTRX = Y

BTS: GENA = Y, EGENA = Y, CMAX = 100 %

The TSL data rate is signal level and interference dependent (capacity limitations are nottaken into account in this example). See the table below:

RLC/MAC Data Rate (FTP Download on 2 TSLs)

0

20

40

60

80

100

120

-65 -70 -75 -80 -85 -90 -95 -100 -105

Signal level (dBm)

kbps

No Interference

C/I 25 dB

C/I 20 dB

C/I 15 dB

Table 28 RLC/MAC data rate dependency on signal level and C/I (two TSLs)

In the dimensioning example below the following average EGPRS RLC/MAC TSL data rateis used:

35 kbit/s (BCCH layer)

Typically best C/I TRX preferred for maximum throughput depending on frequency plan thiscan be either BCCH or TCH TRX. In the example above the BCCH TRX is preferred.


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5.3.3 Available Capacity

Before any calculation the size of the Free RTSL must be defined.

TRX 1

TRX 2

BCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCH

TS TS TSTS TSTS TS TSTS TSTS TS TS TSTS TS TSTS

TS

TS

=CDED

=CSW Territory

TS =(E)GPRS Territory/Additional capacity

BCCH =Signaling

TS =Free TSL for CSW

TS =CDEF

Territory border

GTRX

GTRX

GENA

EGENA

CMAX

TRX 1

TRX 2



TS

TS

=CDED

=CSW Territory


BCCH =Signaling


TS =CDEF

Territory border

TRX 1

TRX 2



TRX 1

TRX 2

BCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCHBCCH TS TS TS TS TS TSSDCCH

TS TS TSTS TSTS TS TSTS TSTS TS TS TSTS TS TSTSTS TS TSTS TSTS TS TSTS TSTS TS TS TSTS TS TSTS

TS

TS

=CDED

=CSW Territory


BCCH =Signaling


TS =CDEF TS

TS

=CDED

=CSW Territory


TS

TS

=CDED

=CSW Territory


BCCH =Signaling


TS =CDEF

BCCH =Signaling


TS =CDEF

Territory border

GTRX

GTRX

GENA

EGENA

CMAX

Table 29 Territories

Free RTSLs between CS and PS territory required in order to serve immediate incomingCS calls without blocking.

CS downgrade if less RTSLs free in CS territory, PS territory downgrade triggered

CS upgrade PS territory upgrade can be triggered if at least that amount of RTSLsfree

Free TSLs for up and downgrade can be controlled by BSC parameters (see the tablebelow):

TSL number af ter CS down grade

TRX number 1 2 3 4 5

70 0 0 0 1 1

95 1 1 1 2 2

99 1 1 2 2 3

TSL number af ter CS upgrade

TRX number 1 2 3 4 5

1 0 1 1 1 2

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