Nortel_V16_BSS_IM_v9

1 Nortel Confidential Information

Nortel V16 validation for T-Mobile USAIM campaign management with WQAIM BSS functionality introduction

November 7, 2006Version 9

2 - Nortel Confidential

Workshop Agenda

> Introduction> IM campaign management with Nortel BSS V15

• CPT-based scripts and associated process

> IM functionality with Nortel BSS V16• BSS and OMCR operational considerations

> WQA platform introduction• WQA tool administration and overview

> WQA-IM post-processing module• Principles, inputs, outputs

> WQA in the end-to-end T-Mobile RF Engineering Process• Workflow, process considerations

> WQA-IM hands-on demonstration• Using field IM campaign data from NY


> End-to-end frequency planning process

IntroductionScope of workshop

RF Engineering

inputs

IM campaignexecution

IM campaign

Post-processing

Frequencyplanning

Tool(AFP)

Frequencyplan

change

Engineering activity

Network activity

Nortel tools or features delivered to T-Mobile

V16 IM WQA FPC

IMC/I

Focus of this chapter


Agenda

> BSS functionality overview

How the feature works and does without user intervention

> BSS operational aspects

What the feature requires as user inputs


Agenda




IM campaign management in V16BSS functionality overview

> V16 introduces a BSS-based solution for the Interference Matrix• Feature 16411

> Regular subscriber measurement reportsare used to build C/Idistributions between(BSiC/BCCH) couples

> XML files generated atSDO for further post-processingwith the WQA tool

WQA


BSS functionality descriptionNeighbor cell management (1/2)

> Main inputs to the IM campaign :• List of cells which will perform IM measurements• List of BCCH frequencies to scan

> The campaign is based on GSM standard mobile reporting procedure> The BSS will fill SYSINFO messages up to their maximum capacity of

32 “neighbors” , so as to encompass :• Real neighbors (declared at OMCR for handover purposes)• Fake neighbors (not declared as real neighbors, based on the BCCH list)

> Handovers to fake neighbors are prevented thanks to the usage ofdissuasive radio parameters (e.g hoMargin = 63)

> The same neighbor list (real+fake) will be kept during an IM cycle• Upon completion of cycle, original “real” neighboring plan is reinstated

> The number of cycles to perform will therefore depend on :• Actual real neighboring declarations (and associated BCCH frequencies)• Depth of the BCCH scan list


BSS functionality descriptionNeighbor cell management (2/2)

> Example : • BCCH scan list : 100 frequencies• Average of 17 real neighbor cells declared per serving cell• 6 cycles are required to collect measurements on all 100 frequencies

Cycle #1(32)

Cycle #2(32)

Cycle #5(32)

Last Cycle #6(25)

Declared Neighbors

FakeNeighbors

100 Frequencies to scan

15 15 15 8

17

15

17

15

17

15

17

8

17+15+15+15+15+15+15+8 = 100


BSS functionality descriptionCycle management (1/2)

> A given cycle is associated with 1 neighboring plan

> Upon completion of the cycle, the data is transferred from BTS to BSC, and then from BSC over to the SDO

IM start1 per BSC Cycle 1 with neighbouring plan 1

Start Meas.End Meas.M

eas.

D

urat

ion

Meas. period

…

Cycle p with neighbouring plan p

Data Collection Report

Post Processingproduct

OMC-R BSS

Mobile

Cyc

le d

urat

ion

Dataretrieval

Neighbouring plan setting

Data Collection Report


BSS functionality descriptionCycle management (2/2)

> The timing of the cycle mechanism is set via a set of configurable parameters :

• ciBgtMeasurementTime• representing the time of start of the first measurement cycle,

• ciBgtReportingCycle• representing the duration of one measurement cycle and consequently the

periodicity of the report to OMC,• Configured in practice in increments of 20 minutes

• ciBgtMeasurementDuration• inside a period of one cycle, the operator can specify the duration of the real

phase of measurement.• Configured in practice in increments of 15 minutes


Examples


BSS functionality descriptionMessage exchange (1/2)

> Cycle start> BSC

automaticallypopulatesSYSINFOwith fakeneighbor infowithoutuser interventionnor scripts

OMC-RW-NMS BSC BTS MS

First Cycle

IM_Freq_Meas TGE

Ack TGERGE

(Ext_)Current Cell Params

ciBgtReportingCycle timer start

Meas Report on real neigh

(Ext_)Neigh Cell Params

(real + Fake freq)

SysInfo 5, 5bis, 5ter, 2, 2bis, 2ter, 13

(BA list real + Fake freq)ciBgtMeasurementDurationtimer start

ciBgtMeasurementTime

ciB

gtM

easu

rem

entD

urat

ion

Meas Report on real+fake neigh



ciBgtMeasurementDurationtimer reset

start distribution req

start distribution ack


stop distribution ack

stop distribution req

All TRXs

BSC BTS MS

First Cycle

IM_Freq_Meas TGE

Ack TGERGE

(Ext_)Current Cell Params

ciBgtReportingCycle timer start

Meas Report on real neigh

(Ext_)Neigh Cell Params

(real + Fake freq)

SysInfo 5, 5bis, 5ter, 2, 2bis, 2ter, 13

(BA list real + Fake freq)ciBgtMeasurementDurationtimer start

ciBgtMeasurementTime

ciB

gtM

easu

rem

entD

urat

ion




ciBgtMeasurementDurationtimer reset

start distribution req

start distribution ack


stop distribution ack

stop distribution req

All TRXs


BSS functionality descriptionMessage exchange (2/2)

> Cycle end> BSC

automaticallyrestoresSYSINFOwith realneighbor info


BSS functionality descriptionMeasurement gathering & reporting (1/3)

> What is measured ?• Serving cell i, neighbor cell j (real or fake)

> IM measurements are done on 1 TRX per sector> TRX selection :

• Performed at the beginning of each cycle (not campaign)• Upon sending the START_DISTRIBUTION message

• The BSC selects the TRX that carries the TDMA with the greatest number of ongoing circuit speech calls (excluding signalling, including pre-empted PDTCH)

• Between two TDMAs that have the same number of such calls, the BSC chooses first the TDMA with the greater AMR HR priority, then the TDMA with the lowest number of PDTCH, and then in case of still equality, with the lowest TDMA number.

• If BSC cannot find a TRX that satisfies the criteria given here above, BSC does not send the activation to the BTS and the cell will not report any measurement for this cycle



> What is reported ?

• A rescaling factor is used for Abis bandwidth optimization allowing to encode any counter value into one byte (with a value below 255).

> For each cycle, C/I distributions are stored on the TRX then reported to BSC

• Distribution data for up to btsMaxNbofDistribPerCycle = 150 BSIC/BCCH pairs are stored - TRX memory constraint

• Data is reported to the BSC upon completion of the cycle, upon receipt of the STOP DISTRIBUTION message

• Only the MaxNbofDistribPerCycle = 113 most represented BSIC/BCCH couples are reported to the BSC (i.e the distributions based on highest amount of samples) – Abis load constraint.

• MEAS Distribution Report messages sent every 5 seconds to BSC, with 6 distributions per message

• Worst case : 113 distributions are reported 19 messages 95 seconds.



>Transfer of data from BSC to OMC :• At BSC level, all Abis messages from cells belonging to same CG (cell-

group, from TMU standpoint) are concatenated• Once all measurement distribution reports are received for a particular CG,

the BSC closes the file and is sent to the OMC/SDO.• An event may affect a cell in the CG (such as trap or lock), leading to the

repetition of the cycle. As such, all CG files may not be closedsimultaneously

>SDO data storage :• Files received from the BSCs are processed and broken down into :

• 1 XML file per cell , per cycle. • Each XML file is optionally compressed using .GZ format (choice at SDO GUI)

• An automated daily TAR process compiles ALL present day XML files into a single TAR archive,

• Nightly procedure (per SdoDailyTimeTransfer parameter)• An “on-demand TAR” option is also available via the SDO MMI

• In case WQA access to the CIBGT data is required before the nightly archiving


> Defense scenarios and impact on IM campaign• TRX lock or trap :

• Data for the ongoing IM cycle is lost• Data gathering, for this TRX, will resume upon next occurrence of ciBgtReportingCycle• there is only one cycle repetition allowed

• BTS lock or trap :• Data for the ongoing IM cycle is lost• Data gathering, for this BTS, will resume upon next occurrence of ciBgtReportingCycle• there is only one cycle repetition allowed

• BSC TMU reset :• Data for the ongoing IM cycle is lost, for all CGs supported by this TMU• Data gathering, for the served CGs, will resume upon next occurrence of ciBgtReportingCycle• there is only one cycle repetition allowed

• BSC restart :• Data for the ongoing IM campaign is lost • Data already uploaded at the SDO is useless• To restart the campaign, an IM ABORT command is required, followed by an IM launch.

• OMC server restart :• Process in the BSS is not stopped.

BSS functionality descriptionDefense scenarios


Agenda




BSS operational aspectsFeature pre-requisites> Feature restrictions :

• Hardware :• Not available on S2000 & S4000 BTS products

• Software • Requires V16 software on BSC & BTS

• IM campaign can be launched on a V16 BSC with V15 BTS • There will be no reports from V15 BTS

> Inputs gathering :• List of cells on which IM measurements are to be performed• List of BCCH to be scanned

• These inputs can be entered manually at the OMC MMI or be prepared in external files to be uploaded.


> From the OMCPerformance Menu

BSS operational aspectsIM campaign activation at OMC (1/9)


BSS operational aspectsIM campaign activation at OMC (2/9) File menu

Allows to load/save IM campaign dataEdit menuTo add cells in the campaignBSC menuTo set the IM campaign general parameters

Add buttonto add BSCs in the campaign

Check buttonTo run semantic checks

Estimate buttonto obtain an evaluation of the campaign duration

Launch buttonto activate the campaign


> Manual setting of the general campaign parameters (applicable at BSC level) :• Dialog window :

• ARFCN (range or list)

• CiBgtReportingCycle• 20min increments

• CiBgtMeasurementTime• CiBgtMeasurementDuration

• 15min increments• Fake BSIC




> Alternative :Import of an input file(“aCIBgtCfg” file)

Example Format

Campaign parameters for BSC 244 :CiBgtReportingCycle = 12*20min = 4HCiBgtMeasurementTime = 960min = 16h00 (= 4pm)CiBgtMeasurementDuration = 14*15min = 3H30minFakeBSIC : BCC = 0 , NCC = 0All ARFCN listed : 541,554,555,558,621,654,687

Note : the input file may also only contain the [BTS] portion,in which case the system will only populate the list of cells

for the campaign.This smaller file is referred to as <Network_BTS>in the documentation.

The remaining IM campaign parameters (timing, frequencies to scan) can then be configured via the GUI.



> Pre-checks (1/2) : Consistency checks between network configuration and interference matrix inputs • parent btsSM of the cells that will be activated is hardware compatible• cells are all parented to a BSC release V16, not locked• Interworking with CDA (same BSC) and RMD (same cells)• ciBgtReportingCycle > ciBgtMeasurementDuration• Interference Matrix is not already running for every BSC• ARFCN are all in same band (e.g 1900)• No more than 100 BCCH frequencies are required.• Cells do not already have 32 real neighboring cells.

• If one cell already has 32 real neighbors, the operator is warned and asked whether to keep the cell in the list. If the operator decides to keep the cell in the list, the check must not be blocking during execution.

• It is advised to limit the number of neighbors to 31 to leave room for measurements on 1 “fake” BCCH



> Pre-checks (2/2) : example

Concurrent usage of RMD



> Estimation of campaign duration is provided prior to launch

List of BCCH frequencies to

scan

Real NeighborPlan

Number of cycles

Timing parameters

Total IM Campaign duration

Assumption : each cycle is executed once



> Launch • Via MMI button

> Abort• From BSC menu

> Check status • At MMI

> Dynamic flags :• 2 levels :

• interferenceMatrixRunningOnBts• interferenceMatrixRunningOnBsc

• Displayed at MMI via Get command

> Activation status :

End of IM campaign can be detected wheninterferenceMatrixRunningOnBsc is back at “NO” on all BSCs



> Self-enforced “network freeze” : the following activities are prevented by the system, during execution of the IM campaign• BTS reparenting

• As this require the bts object to be deleted on source BSC• Neighbor declaration

• Creation/deletion of neighbors prohibited for cells part of IM campaign• Change of parameters other than BSIC/BCCH allowed on existing neighbors

• RMD on same cells where IM campaign is running• BTS processing limitation

• CDA on same BSC involved in an IM campaign• BSC disk capacity limitation

> Frequency plan change• (Non-BCCH) TRX additions are possible (but lock of bts cycle lost)


CDA/RMD/IM/CT/CPT concurrent usage possibilitiesV16

Concurrent usage is possible without restrictionsConcurrent usage is possible - restriction of usage to a subset of cells may apply*Concurrent usage is not recommended / not technically possible

Limitations applicable to individual features : -CDA : activation on max 80 cells/BSC-CPT : max number of 6 cells/BSC, max 36 traces/BSC-CT : max 12 traces/BSC

*Note : ad-hoc study required, depending on OMC configuration

CDA RMD IM CT CPT

CDA BSC basis

RMD Cell basis

IM BSC basis Cell basis

CT

CPT


BSS operational aspectsSDO data storage

> Compression of IM XML files• ON, by default• Configurable

via SDO GUI• Data Format menu

> Archiving of IM XML files• Automated Nightly “TAR” (@2.00AM)

• SdoDailyTimeTransfer parameter• Manual archiving triggered

via :• SDO GUI

• Archive menu• tarXML command


Main outputs> Interference Matrix C/I distributions (XML files)

• Before archiving :• Naming : <Type><Startdate>.<Starttime>-<Endtime>_-<sessionId>_CELL.<CGI>_-

_<cycleId> • Example : A20050101.1400+0200-1415+0200_-1a9f_CELL.64f00001ab0001_-_03• Location : /SDO/data/CIBgt/YYYYMMDD/<networkId>/<sessionId>/<bscId>/

• After archiving of all XML files produced during the day :• Naming : <Type><Startdate>.<Starttime>-<Endtime>.tar • Example : D20050101.1400+0200-2345+0200.tar • Location : /SDO/data/CIBgt/compressed

> Interference Matrix Configuration File• Naming : aCIBgtCfg_<sessionID>_<time><deltaUTC> • Example : aCIBgtCfg_1a9f_1200+0200 • Location : /SDO/data/CIBgt/YYYYMMDD/<networkId>/<sessionId> • Note : this file can be created manually as input to the IM campaign as well

> Network Configuration files• Generation is independent from IM• Naming :

• aNETWORK_BTS.hhmm (All cell-based parameters)• aNETWORK_ADJCHO.hhmm (Neighbor declarations)

• Location : /SDO/data/network/ YYYYMMDD /<NetworkId>


Agenda



> References


IM functionality in the BSSDocumentation references

> Functional Note :• Description of the feature from a Design standpoint• Reference document PE/SYS/DD/0428, v01.17• Located in the T-Mobile File Exchange @ mynortelnetworks.com

> NTP Operational documentation• Description of the IM activation from an Operations standpoint• NTP : Nortel GSM OMC-R Commands Reference - Configuration,

Performance, and Maintenance menus (411-9001-129)• Section 2.10 : «Interference Matrix Launcher »• Available via Helmsman Express

> SDO specifications• SIE OMCR Data Server – XML part : PE/OMC/DD/014022• SFS OMCR Data Server : PE/OMC/DD/000103• Located in the T-Mobile File Exchange @ mynortelnetworks.com

Nortel_V16_BSS_IM_v9

Documents

frequency plan change

bss operational aspects

real fake neigh

im campaign management

lost data gathering

ongoing im cycle

data collection report

cycle repetition allowed