analyze_optimization process.pdf

8/17/2019 Analyze_Optimization Process.pdf

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Objective & Aims

Procedure flow chart

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www.comba-telecom.com

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Analysis objective

Our main objective is to optimize the network by analysis the

.

Aims of the analysis phase:

• Identified the problem encountered during drive test

• Investigate and verifying the cause of the problem

• Provide solution/recommendation to solve the problem

Improve RF coverage

Reduce call drop rate

Reduce blocked call

Increase system capacity us so an over ac or

Parameter Tuning

Control Interference

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Analysis objective

Nemo Analyzer or Playback would be used for Uu log analysis

c x wou e use or canne og ana ys s

Alarm history and PM counter would be extracted from OSS

• Scanner data is used for RF Coverage/Cell dominance

optimization (L1 analysis)

Nemo Analyer or Playback:• UE log data is used for Call Event failure analysis

rop an a a or a a a

Hand-Over/Neighbor list Optimization

Alarm Histor :• Identify cell status during DT

PM Counters:


• Verify signaling message within network


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Analysis tools

NEMO ACTIX OTHERS

Field Measurement

Tool (FMT) for data

Superstream

multiple data file.

MapInfo for

presentation, driveco ec on.

Playback Function

allows analysis of

enera e ,

statistics and report

based from pre

es rou e crea ng,

customizing events.

Excel workbookDrive

.

Show Call eventsand sequence.

.

Analyze Call eventsand sequence.

.Data

msgs.

based on RSCP and

Ec/No of desired

.

Shows Layer 3

msgs.

Etc.



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NEMO window

Scanner RSCP

& EcNo

UE’s active &

monitor RSCP

UE’s active &

monitor EcNo

Parameter

values to see: etc

SF, RRC state,

BLER, TX

power, CellID

and many more.

Layer 3 and

Map Window:

displays data in

drive route,

shows position

Values & Window to see when analyzing log file. With the RSCP, EcNo,

RRC message

window

to serving cell(s)


message window, we can start to analyze the log file.


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Analysis procedure

1

of DT tool &

route map

ata co ect on

during drive

testing

Post processing

data

Analysis of

problem

Solution and

2

recommendation

.

2. Isolate the reason3

Implementation

.

recommendation


er y ng r ve es

again


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Analysis procedure

Identify the problem

• Using either NEMO or ACTIX to post process data collected

from drive-test in order to provide the statistic result. With thes a s c resu , compare w e se an we can

determine the problem. Note that necessary filtering of the data

is required in order to have a valid statistics. *Etc: filter out the

problem related to measurement tools issue.

•

other reasons resulting to Call Setup Failure and/or Drop Call.

Then further analyze the problem to get the reason.



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Analysis procedure

Isolate the reason

• RF or Layer 1 related problem can be due to many reason:

Non-optimal cell design (location, antenna type/height/bearing/tilt)Wron or bad scramblin code lannin

No dominance server

Poor coverage with low RSCP or blockage issue

Pilot ollution from overshootin cell or too man overla in cell

• Call events can be triggered by many reason: Due to Layer 1 (see above)

Missing Neighbor definition

Handover parameter (delayed and/or requires offset)

Cell selection/re-selection (Can be related to Layer 1) Interference (external or internal)

Tool related (etc; UE problems)

Network problems (etc; Equipment related)



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Layer 1 optimization process

Call event optimization process

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www.comba-telecom.com

11


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Optimization

Improve call Quality,

Accessibility,

Improve

e a n y

Mobility

environment

coverage base on

existing network

base on increase

in subscribers

Optimization?

Parameter tuning

Recommendation

& Change

Antenna tuning



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In-building Layer 1 optimization process

Walk test data

Best active RSCP optimization problem: Poor covera e area No

No

RSCP>-

90dBm Faulty components

Power insufficient

Poor signal penetration

Best active

EcNo > -

EcNo optimization problem:

Pilot pollution

Interference

Overshooting

No Re-walk test pass KPI

Solutions

Implemented

10dB

Yes

High rise

Desire coverage optimization:

None dominance server Yes

Desire

Coverage

Coverage hole

Blockage

o


L1 optimization

completed Yes


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Outdoor Roll-Out flow chart

Preparation of

site information

Change

ro osal

Re-Drive

testin

Implementation

of chan e

Wait for

Acceptance

Ncell review &

planningOptimization

Data post

processing

Route & Custer

definition AnalysisKPI pass?

NO

YES

Sites on air Data post

processing

r ve es ng

when 90% of

sites in cluster

on air

Single sites

verification



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Outdoor Optimization flow chart

Data post

processing

Implementati

on of change

Preparation

Route

planning

re-

optimization

drive testing

Analysis

Drive Testing

Conditional

acceptance

Final

acceptance

Ncell review

& planning

Stats

collectionOptimization

Change

proposal

Reporting

Preparation Planning Analysis & OptimizationMeasurement Acceptance


. .


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Outdoor Layer 1 optimization process

Drive test data

Best active No

No RSCP optimization problem: Poor coverage area

RSCP>-

90dBm

oc age

Shadowing

Far Distance

Best active

EcNo > -

No Re-drive pass KPI

Solutions

Implemented

EcNo optimization problem:

Pilot pollution

Interference

Overshooting10dB

Yes Yes

Overlapping

Desire coverage optimization:

Desire

Coverage

o Coverage hole

Shadowing


L1 optimization

completed Yes


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Layer 1 optimization process

Always provide a footprint of RSCP, EcNo, Best server, Pilot pollution plot

to have a clearer view of the problem area.

RSCP plot

Problem

area #2

From RSCP plot,

we can define poor

- ,

and provide solution after

surveying the area and

analyzing.ro em

area #1



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Call Event optimization process

Drive test process

oun

problem Attract

KPI

report on tor area

Change

Request

No NodeB faulty /

No Re-drive

Check

KPI needed

Yes

Yes

counters

Parameter tuning /

Antenna tuning Implementation

Yes Yes



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Change Proposal procedure

Change

Proposal

Verification

Drive

Yes YesNo

Customer /Operator

Update

database

YesYes

Report to

or network

engineer

of change

proposal

customer on

the failure

implementation



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Optimization Issue

In optimization, we have different scenario resulting in

Problems Likely reason Solution

Missing Neighbors Poor neighbors planning from

planner

Review/add/del neighbors

Co-Scramblin Code Incorrect database or oor Chan e SC of Co-SC cells

assigning of SC from planner

Fading (Signal degrading

rapidly)

Cornering / Shadowing / IBC

spillage

Fine tuning antenna or

parameter tuning

Pilot pollution (Bad EcNo

quality but good RSCP level)

Overshooting or spillage IBC

signal

Remove unwanted signal or

overlapping coverage

Poor coverage (RSCP level Blockage or no LOS Change higher gain antenna orbelow -105dBm) implement repeater solution

No dominance server (RSCP

good but poor EcNo)

Too many serving cells in an area /

Too many LAU in the borders

Reduce overlapping coverage

and create the most dominance


analyze_optimization process.pdf

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