21688231 proposal for gsm network optimization audit tsel

7/29/2019 21688231 Proposal for GSM Network Optimization Audit Tsel

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PT.Telkomsel

Proposal for GSM Network Optimization

September 2009

HS


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Overview

Optimization is all actions intended to tune all aspects of the GSM networkperformance, covering access network, core network, and transmissionnetwork.

Access network optimization procedure consists of two phases: cluster testingand system integration optimization. In other words, the initial pass of the RFoptimization will be performed as a part of cluster tests: the second, moredetailed, tuning phase will occur after completion of all cluster tests, whichoccur after activation of all cell sites in the GSM network.

The primary reason for breaking the optimization work into two phases is toreduce the time and resources required to complete the cluster test cycles.


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Objective

To ensure the achievement of acceptable coverage

To maximize the quality of service

To maximize the network efficiency (including load balancing)


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Consideration

System stability and performance : To easy and simplify optimization

process, instability and bad performance of system should be clarified.

Coverage : Can be adjusted by power settings (total, overhead),

antenna tilting and orientation, hand-off area and so on.

Capacity : Trunk lines, Number of traffic channel and elements should

be equipped with sufficient quantity

Parameters : Can be adjusted for the better coverage and capacity

adjustment


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Project Organization

PT.Telkomsel

PM & Local Engineer

Optimization Audit Support Management

PM Network Optimizations

Vendor

PM & Local Engineer

Co-work

AGTINDO


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START(Preparation)

Survey & Simulation Network Evaluation

Optimization

Target & Method Decision

Optimization

Execution

Optimization Evaluation

Performance

Objectives ?

END

YES

NO

Preparation: BTS info. & Parameter Review

o BTS position, type, output power, antenna info.

o Frequency Status

o Neighbor list

Site Survey & Simulation

o Drive test & walk test

o Rx Quality, Rx Level, Coverage plot

o Handoff performance

Network Evaluation: Field measurement & analysis

o Field measurement with Tems Investigations

o Call event analysis

- fail and dropped call

- signal distribution (Rxqual, RxLev, SQI, etc)

Reduce bad quality area & Find Optimization method

o Weak signal and Freq Interference

o Parameter error / Missing Neighbor, etc

o Hardware trouble, etc

Execution, Evaluation and feedback

Optimization Process (1)


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Field measurement & analysis

- Coverage (bad area) analysis- Coverage overlay ratio

- Call quality(drop and fail rate)

NMS data analysis

- System type / performance

- System statistics analysis

(C/D rate, Call fail, etc)

Optimization Target

- Coverage

- Call quality

Decision forOptimization method

Coverage Improvement

(Shadow & Bad area)

Traffic Balancing

(site / sector based)

System performance

improvement

Accomplishment & Evaluation

- Issue based optimization

- Evaluation for target goal

Optimization result

Feedback for engineering

System facilities check

System type change

Parameter error correction

Recommendation

Trouble shooting

Optimization Process (2)


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Setup

Field measurement

CQT analysis

CQT report

Action plan for opt.

CQT Report & Opt. Action Plan Report & Presentation

Project setup

Kick off meeting MS registration

Data analysis

- BTS info.

- Parameter

- etc.

1st CQT 2nd CQT

Access Network Optimization

BTS Opt.

- Site survey

- Fisical Tunning

- Simulation

- Cluster opt.

- etc.

Parameter Opt.

- System parameter

- Access parameter

- Handoff

- Neighbor list adjust

- etc 2nd CQT Report & Presentation

Work Plan

1st week 2nd ~ 3rd week 4th week ~ 11th week 12th week

Note 1) CQT: Call Quality Test

2) Opt.: Optimization

)Basic Data Analysis & CQT )Optimization (System, Parameter, etc) CQT & Report


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Detail Items of Optimization

BTS Basic Test(1): Basic Parameter Review

Basic items to be checked

o BTS information and Hardware characteristics- Site Name and Type

- Antenna type, height, directions and tilting degree, ( VSWR )

o Target service area of the base station and design capacity

Parameter settings to be checked

o Neighbor list of each sector

o Handoff parameter

o Access parameter

o Traffic channel parameter (Capacity)

o Frequency / Channel Number

o Power control parameter, etc

Basic call test

o Mobile to mobile, mobile to fix lines, fix lines to mobile call test: origination & termination

o Handoff test: in idle and dedicated mode


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BTS Basic Test(2): Considerations

Database & fisical cheking

o Operator input error, Database Parameter loading error for BTS.

o Cable connection error between BTS and antenna (VSWR).

RF environment /Condition check

o Using real call ( drive test & walk test with measurement test ).

- This is used in most cell optimizations and field trials. Check for Interference, Speech quality, Signal

level and Handover (and data com transfer / GPRS check).


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o Set the service area

o Find the coverage shadowing area / Indicate the shadowing area on the map

o Run field drive test / walk test

o Set the BTS transmit power and system parameters

o Optimize coverage

o Define the handoff area and optimize the handoff region: BTS power and antenna direction

o BSC parameter and ensure forward and reverse link balanceo Optimize FER/AMR

Considerations

Center Cell Neighbor Cell

Cluster


Cluster Test

Goal

o To verify the required basic function, performance and network stabilitythrough field test (classify the cluster)


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Network Integration(1)

Optimization Target Area

o Weak signal areaso Call drop areas

o Access failure areas (call fail)

1) Weak Signal Area

Problem

o Check Transmit power

o Change antenna tilt

o Antenna replacement

Solution


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o Weak signal areas

o Call drop areas


2) Call droop areas

Problem

o Check the frequency

- Adjust interferences

- changes frequency or ant fisical tunning

o Check the neighbor list

- Missing neighbor list and- erroneous neighbor list order

Solution


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o Weak signal areaso Call drop areas


3) Access failure areas (call fail)

Problem

o Check the access parameter

- capacity, frequency, signal power

o Excessive IDLE handoff: coverage adjust

o MSC, zone border: check registration

Solution


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Hardware and Parameter Trouble shooting

o Hardware troubleo Handoff and access parameter

1) Hardware trouble

Problem Solution

Type Phenomenon Optimization scheme

Antenna VSWRCoverage reduction

High Tx_adj (above + 10dB)Antenna replacement


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Hardware and Parameter Trouble shooting

o Hardware trouble

o Handoff and access parameter trouble

1) Handoff parameter trouble

Problem Solution

Type Phenomenon Optimization scheme

Poor IDLE handoff Temporary NO SERVICE during H/O Neighbor list check

Poor H/O Call drop, etc Neighbor list and signal check

2) Access parameter trouble

- Traffic channel parameters

- Multi-path delay compensation

21688231 proposal for gsm network optimization audit tsel

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