gsm traffic statistics analysis

8/18/2019 GSM Traffic Statistics Analysis

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GSM Traffic Statistics Analysis

ZTE university


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Course Target

When you finish studying this

course， you can：Master ZTE traffic statistic

Master the meaning of parameter items of

common-used traffic statistic

Master the methods to analyze and position the

problems making use of traffic statistic


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Contents

ZTE Traffic Statistic !er!ie"

#efinitions f Main Traffic Statistic $arameters

$osition And Analyze $roblems Making %se f Traffic

StatisticTraffic Statistic Analysis Cases


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ZTE Traffic Statistic Overview--The Function Of Traffic

Statistic Analysis

Optimization

scheme

Radio NetworkOptimization

Data collection

optimization scheme

implementation

ight ad!ustment

solution and

evaluation

Traffic statistic

analysis"now network performance

inde# $rovide clients with

%uantitative service guidelines

&onitor network performance

$osition and analyze network

pro'lems

(mprove network running

%uality


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ZTE Traffic Statistic Overview--ZTE Traffic Statistic Introduce

Traffic

statistic

Alarm

statistic

Performance

index

Measurement

statistic

CS trafficbasic

measurement

BTS

measurement

Radio

measurement

A interface

measurement

Resourceseizure

measurement

PS traffic

measurement


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ZTE Traffic Statistic Overview-- Traffic Statistic Index

riginal traffic statistic

inde&

)D**+ congestion rate

)D**+ assignment

success rate

)D**+ call drop rate T*+ congestion rate

T*+ assignment

success rate

T*+ call drop rate

+andover success rate

Random access success

rate

$aging success rate

,correlative inde#-

Synthetical traffic statisticinde&

Traffic.to.drop ratio

Worst cell ratio

T*+ assignment success

rate ,*hina /nion definition- Radio connection rate


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ZTE Traffic Statistic Overview --CS Traffic Basic Measureent

CS traffic

basic

measuremen

t

'asic measurement task is the measurement "hich produces basic

performance report， including resource status、 ser!ice status、 channel

(uality etc)， can reflect the total net"ork status more roundly)

Q3 module

measurement

Carry out statistic according to the modules， mainly including

assignment and hando!er* and the load of C$%) Statistic is mainly

responsed to +MM* and SMM is used to measure cpu,s burthen)

Q3 cell

BTS

measuremen

t counter

Measure 'TS po"er 、 +&le!el、 +&(uality and TA in terms of cells*

then accumulate the measurement !alues got from T+. po"er control

counter and report the statistic)

３

２


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ZTE Traffic Statistic Overview --BTS Measureent

Power

control

measuremen

t

'TS decides "hether to control MS/s0or 'TS/s1 po"er or not based on

+&le! or +&(ual in measurement report *and carries out statistic according to

different po"er control factor)

Carrier

frequency

servicemeasuremen

t

2t/s to measure "hether channel acti!ation、 assignment、 hando!er are

successful "ith carrier fre(uency as unit* and measure carrier fre(uencyinterference bands、 MA. and M23 uplink4do"nlink signal le!el)

Paging

measuremen

t

Carry out statistic paging drop and the length of (ueue "ith carrier fre(uency

as unit)

Carrier

fre(uencybasic

measuremen

t

Measure carrier fre(uency/s ser!ice occupation times and occupation time

about TC5 and S#CC5)

２

４

３


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ZTE Traffic Statistic Overview-- !adio easureent

Cell radiomeasurement

Measure interference and 6os of per channel "hich is occupying andidle state)

Radio access

measurement

Measure MS/s radio random access process* including access trying

times、 processing times 、 successful times "ith different reason)

SDCCH

measurement

Measure success times and success rate about S#CC5 assignment*

allocation7 occupation etc)* reflect ser!ice of S#CC5)

TCH/F

measurement

Measure success times and success rate about TC548 assignment*

allocation7 occupation etc) *"hich is based on configure channels and

ad9ust parameter)

２

４

３

SAPI3

measurement

Measure connection times 、 recei!e times and transmitting times of

point to point SMS)

５


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RMM

assignment

measurement

#escribe +MM assignment* including assignment attempt、 e&ecutingand (ueue "ith e!ery reason)

RMM call

drop

measurement

#escribe all kinds of channel in signaling flo"、 +MM call drop times、

call drop reason etc))

Handover

reason

measurement

Carry out statistic on e!ery hando!er0out1 attempt according to e!ery

reason)

Handover

common

measurement

Carry out statistic hando!er process "ith e!ery reason*including

attempt、 e&ecuting、 success and fail times*reflect hando!er success

rate)

６

７

９

８

Handover

synchronization

measurement

１０

Carry out statistic all kinds of synchronism hando!er times)


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Neighboring

cell handover

measurement

Carry out statistic on mutual hando!er by selecting some cells and theirneighboring cells)

Paging

measurementThe meaning and measurement point of paging measurement counter)

Abisinterface

signaling

statistic

Carry out statistic on all kinds of signaling numbers transmitted in Abis

interface)

Radio

resource

usability

measurement

Measure usage of each cell radio channel resource)

１１

１２

１４

１３

HR statistic

measurement

2t/s added 5+ basic measurement according to subscriber/s need* mainly

describe resource status* ser!ice status and dynamic changeo!er status of

TC545

１５


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ZTE Traffic Statistic Overview --A Interface Measureent

A interface

signaling statistic

measurement

carry out statistic on signaling numbers of 'SC production 、 for"arding

and reception based on signaling name and signaling type)

A interfaceassignment

、

call

drop、

hando

ver statistic

measurement

Carry out statistic on assignment 、 call drop and hando!er times of A

interface* carry out statistic and classify on failure status* it/s helpful to

position and sol!e problem)

SCCP

connection

measurementand ground

circuit

resource

usability

measurement

Measure SCC$ links/ establish status and usability of ground relay circuit

resource)

３

２


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ZTE Traffic Statistic Overview --!esource Occu"ation

Measureent

TRX LAPD

link

measurement

Carry out statistic on signaling alternant of each :A$# signaling link "hich

connecting T+. "hen it/s transmitting and recei!ing messages !ia :A$#

board *"ith T+. :A$# link as unit)

O&M LAPD

link measurement

Carry out statistic on signaling alternant of each 7M :A$# signaling link

"hich connecting T+. "hen it/s transmitting and recei!ing messages !ia:A$# board *"ith T+. 7M :A$# link as unit)

SCCP link

measurement

Carry out statistic on signaling alternant of each SCC$ link "ith SCC$ link

as unit)

Processorload

measurement

Carry out statistic on C$% load 、 internal memory 、 ser!ice load and

file system load of each SMM and +MM module* "ith module as unit)

２

４

３


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ZTE Traffic Statistic Overview --#S Service Measureent

PS basic

measurement

2t measures $S basic performance report* including resource status 、

ser!ice status and channel (uality etc)* can reflect comprehensi!ely total $Snet"ork performance)

NS

measurement

Carry out statistic on 'S;C links/ data transmition 、 signaling

alternant and abnormal reason etc) "ith single 3S;C as measurement entity)

BSSGP

measurement

NSE

measurement

Carry out statistic on paging 、 status indication message 、 ';C

signaling reset times etc) "ith single 3SE as measurement entity)

２

４

３

PS traffic

statistic and

resource

management

measurement

$S traffic statistic measure cell ser!ices) +esource management mainly

measure 'SC system resource usage)

５

Mainly measure messages transmitting and recei!ing in Gb interface on

'SSG$ layer of G$+S ser!ice)


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Contents






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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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#efinitions f


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Contents






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#osition And Analy2e #ro'les with Traffic Statistics-- Traffic

Statistic Analysis Content

Call Drop ProblemsAnalysis

SDCCH assignmentproblems analysis

TCH congestionproblems analysis

SDCCH congestionproblems analysis

Handover problemanalysis

TCH assignmentproblems analysis

Traffic )tatistic 0nalysis *ontent


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#osition And Analy2e #ro'les with Traffic Statistics

Whole $rinciple of Traffic )tatistic 0nalysis

Whole $rinciple： 1rom whole pro'lem to the particular pro'lem2 fromone.day network inde# o'servation to one.week network inde#2 from single

inde# to their correlation2 from the key cells to su'ordinate cells3

4efore Traffic )tatistic 0nalysis： *ollect overall data2 including all kinds ofperformance reports and measurement data2 and need to know such 'asic

information as networking structure3 *arry out Traffic )tatistic 0nalysis ： 4ased on the principle of 5grasp the

situation macroscopically2 handle it microscopically6 and characteristics of

traffic statistic data2 traffic statistic analysis is a process from the whole

network performance measurements to the cells performance

measurements2 and a gradual process from the main inde# to

su'ordinate inde#3 (t analyzes network performance inde# first2 with a cleargrasp of the whole network inde#2 then determines which inde# are worse2

finally analyzes the main cells which cause worse inde#3

*om'ine with other network optimization tools： During traffic statisticanalyzing2 it needs to com'ine with other network optimization tools to

position and analyze pro'lems3


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TO$ 0nalyze &ethod Description of TO$ 78 &ethod9 /se data sort and filter functions of

E:*E or other software tools to sort each data from 'ad to good3

Thus facilitate connecting each data 2finding the rules and locating

pro'lems more easily3

*arry out studying and contrastive analysis on the su'.item;s

statistic function of 4)*.level traffic statistic report3 (f certain important inde# ,such as call drop rate、 successful

handover rate- are found a'normal in 4)*.level traffic statistic

report2 then carry out cell.level traffic statistic to analyze its more

detailed content3

*heck the cells which single inde# is a'normal and has more

a'solute times of failure ,call drop、 congestion、 handover failure2etc- 3

*om'ine the two parameters2 percentage and a'solute times of

failure ,call drop、 congestion、 handover failure2 etc-2 to decidewhether it needs to adopt further measures3


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话统分析总体思路

#osition And Analy2e #ro'les with Traffic Statistics--Traffic

Statistic Analysis 3eneral Idea

CELL Level

Report

High Call

Drop Rate

High Congestion

Rate

High Handover

Failure Rate

Alarm InformationCS Basic Service

Measurement

Carrier Frequency

Service Measurement

Cell Radio

Measurement

CS Basic Service

Measurement Alarm Information

Radio Access

Measurement

Cell Radio

Measurement

Alarm InformationHandover Reason

Measurement

Handover Common

Measurement

Adjacent Cell Handover

Measurement

CS Basic Service

Measurement

BSC Level

Report


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#osition And Analy2e #ro'les with Traffic Statistics--Traffic

Statistic Analysis 3eneral Idea

The other optimization methods DT： )imulate )u'scri'er make calls in moving

state2 0nalyze coverage、 %uality、 handover 、signaling3

*


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#osition And Analy2e #ro'les with Traffic Statistics--Index Analysis Filter

Method

E%uipment

hardware pro'lems

(nterferencepro'lems

*overage

pro'lems

Commonness $roblems

+andover

pro'lems

Other radioparameters pro'lems

。。。

2ndi!iduality $roblems

1irst *ommonness

)econd (ndividuality


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$osition And Analyze $roblems "ith Traffic

Statistics

Commonness factors lead to bad


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#osition And Analy2e #ro'les with Traffic Statistics 4

Coon #ro'les


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#osition And Analy2e #ro'les with Traffic Statistics--

Coon #ro'les 2nterference

Traffic Statistic AnalysisTraffic Statistic Analysis Method of $osition and +esol!eMethod of $osition and +esol!e

8re(uency check： Analyze inner

interference "ithin same or ad9acent

fre(uency point；

S"eep fre(uency test： search e&ternalinterference；

#T： Check interference and signal (uality

status of the problem section D

Ad9ust 'TS/s transmit po"er of correlati!e

cells、 antenna do"ntilt or fre(uency

point etc) to a!oid interferenceD

Enable function of 5$， #T.， #$C etc) D

+esol!e e(uipment problems 0such as

T+. board self-e&citation、 antenna

intermodulation1)

CE:: traffic statistic： Analyze interference

bands le!el

CS basic measurement： Analyze discipline of

interference bands appears： change "ith time

and traffic capacity

'TS measurement： $osition T+. le!el

interference bands；

5ando!er reason measurement： The ratio of

%:4#: +6 hando!er to all hando!er ；

Cell radio measurement： Analyze le!el and

(uality status of cells)

Abis interfaces signaling trace： Analyze cells

and T+.s "ith interference)


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Coon #ro'les Co!erage $roblems

DT in weak coverage area=

0d!ust network parameters according to

DT result=

4T) transmitting power2 antennadowntilt and height2

R#lev>0**E))>&(N>&)2 the neigh'or

relation2 R:E?>0**E))>&(N of

handover candidate cell3

0d!ust coverage2 avoid over.

coverage、 owe.coverage and aloneisland phenomenon=

0dd 4T)3

*ell traffic statistic9 Worse /@D

R< and "$(=

$ower control performance

measurement9 average of /@Dsignal level is too low=

*ell radio measurement9 Times of

low R:.evel have higher

percentage=

+andover reason measurement9

Times of rescue /@D R#.lev

handover has higher percentage=

&ethod of $osition and Resolve&ethod of $osition and ResolveTraffic )tatistic 0nalysisTraffic )tatistic 0nalysis


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#osition And Analy2e #ro'les with Traffic Statistics--Call

%ro" Analysis

Call #rop Type

Radio ink 1ailure call drop

+andover 1ailure call drop

0$D call drop


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%ro" Analysis

Analysis Frae

BSC +evel

"erforance re"ort

CE++ level

"erforance re"ort

BTS easureent

Cell radioeasureent

CE++ +evel

"erforance re"ort

CS 'asic

easureent

Alar statistic

Coon "ro'les

analysis

Individuality

"ro'les analysis

Alar analysis

Traffic statistic

analysis

Si)nalin) analysis

Other o"tii2ation

ethods

Fro whole to

"articular

Carrier fre5uency

level

Easy to "osition

and analy2e

First coonness

then individuality

Execute and solve

"ro'les

/ , 6 7

Solve Call

dro" "ro'les

Confir hi)her

call dro" cell

Analy2e call dro"

factors

Confir

call dro" ty"e

Confir T!8 level

call dro"


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%ro" Analysis 2mproper setting of hando!er parameters

Traffic Statistic AnalysisTraffic Statistic Analysis +esol!e Methods+esol!e Methods

Add neighbor relation in reasonD

Ad9ust hando!er parameters)

Check hando!er parameters* find

unreasonable parameters settingD

5ando!er common measurement* check

hando!er out failure statusD

5ando!er common measurement* check

hando!er reason and percents of each kind

of hando!erD

Ad9acent cell hando!er statistic

measurement lo" success rate of

hando!er out （ aim at certain cell）， findtarget cell "ith lo" hando!er success rate

and looking for causeDCS basic ser!ice measurement hando!er

times4call times ＞）


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%ro" Analysis %:4#: 2mbalance 0Tower top amplifier 、 +$0、 0ntenna azimuth1

Check to"er top

amplifier 、 C#%、 +#%、 'TS boardsand +8 feederD

Check antenna feeder) Check antenna

azimuth and do"ntilt "hether according

"ith design criterionD check antenna

feeder* 9umper feeder is connected rightly

and connecters are connected tightly*

feeder is undamaged* make sure standing

"a!e rate under normal range)

CS basic ser!ice measurement Analyze

%:4#: A!erage+&:e!D

Abis interface signaling trace Analyze

%:4#: +&:e!D

Cell radio measurement Analyze %:4#:+&:e! distributing)

+esol!e Methods+esol!e MethodsTraffic Statistic AnalysisTraffic Statistic Analysis


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切换问题分析

#osition And Analy2e #ro'les with Traffic Statistics4

&andover #ro'les Analysis 5ando!er Analysis 2dea


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MSC?

'SC? 'SCF 'SC

MSCF

1 $


&andover #ro'les Analysis General Analysis 2dea

*ells with handover pro'lems9 0ll cells or individual

cell3

+andover direction of pro'lem cells 9 +andover out

cell failure or in cell handover failure=

O'!ect of handover failure9 4etween service celland multi.cell or individual cell3


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&andover #ro'les Analysis $ossible 8actors influencing 5ando!er

Success +ate*ommon $ro'lems

already analyzed

/@D (m'alance

E%uipment

$ro'lem

+andover

$arameters

(rrationality

*overage

(nterference

:ead :o" 5ando!er

Success +ate


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2mproper setting of hando!er parameters


&andover #ro'les Analysis

Check $'GT、 rescue hando!er etc)hando!er le!el threshold* setting of

hando!er function s"itch "hether correct)

+esult of hando!er times !s TC5 calloccupation success times is disproportion)

2f hando!er4call＞， $ing-pong hando!ere&ist in all probability* should check

hando!er parameters setting and ad9ust

0least time space of inter-cell* $'GT

5o:e!Ths etc)1

Cell performance report :o" hando!er

success rate* more hando!er failure timesD

'TS measurement filter T+.s "ith more

hando!er failure times)

'asic measurement analyze e!ery

hando!er factors percent* $'GT hando!er

percent too high or too lo"D

5ando!er statistic hando!er find out t"o

cells lead to hando!er failure)



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Comprehensi!e analysis



E&tend capacity of target cell or traffic

proportionD

Check hard"areD

Ad9ust hando!er parametersD

ptimize ad9acent cellsD

$erformance report of cells le!el target

cell congestionD

CS basic measurement lo" hando!er in

success rate* maybe hando!er in cell

hard"are problems or has interference

etc)D :o" hando!er success rate maybe target

cell congestion or hando!er parameters

setting is irrationalityD

Check neighbor relation "hether ha!e

omitted neighbor*single or redundant

neighborD

Check e&terior cell setting of e&terior cellparameters error)



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ther

0fter eliminate commonness pro'lems2 optimize parameters of

ad!acent cells2 analyze and resolve /@D 'alance pro'lems of ad!acent

cells2


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$ossible causes of TC5 blocking

#osition And Analy2e #ro'les with Traffic Statistics-- Analysis

Of TC& Bloc(in)

)hortage of system

capacity or traffic

im'alance

Data configuration

pro'lem

(nterference

*overage pro'lem

0ntenna and feeder

system pro'lem

$arameters setting

pro'lem

TCH Blocking

*ommon $ro'lems

already analyzed

i i A A i ffi S i i


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:ack of system capacity or unbalanced traffic


Analysis Of TC& Bloc(in)

E#tend capacity2 or ad!ust configuration

of 'usy and idle carrier cells=

0d!ust coverage ,ad!ust transmit power

of 4T)2 antenna azimuth2 downtilt2height etc3-=

0d!ust main parameters ,*RO2

R#lev>access>&in>&)2 ena'le traffic+o

function-=

0d!ust priority level and handover

parameters of cells3

Too high traffic capacity in T*+ ,Traffic

per channelA83B-； Too much overflow times2 system 'usy

for a long time= Traffic im'alance ,three cells of one

4T) traffic im'alance2 or several 4T)

traffic im'alance=

0nalyze out serious congestion from

performance reports3

Cudging &ethodCudging &ethod )olution)olution

# i i A d A l # 'l i h T ffi S i i


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Antenna and feeder problem



*heck antenna azimuth2 downtilt2

connection of antenna and feeder

system3

1re%uency point scanning9 results to

same fre%uency point through main

and secondary diversity antenna

measuring=

*ell radio measurement9 signal level2

%uality distur'ing=

)ignaling tracing9 measurement report

analysis3

udging Methodudging Method SolutionSolution

# iti A d A l # 'l ith T ffi St ti ti


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2mproper setting of parameters



0d!ust irrationality parameters setting=

)olve pro'lems3

$erformance statistics report9 !udging

T*+ congestion=

0larm information statistic： 4T) or

TR: pro'lem= 4T) measurement9 check TR:s=

*heck parameters9

R#ev>0ccess>&in>&)2 cell reselect

parameters3


# iti A d A l # 'l ith T ffi St ti ti A l i


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Causes of S#CC5 blocking

#osition And Analy2e #ro'les with Traffic Statistics-- Analysis

Of S%CC& Bloc(in)

引起 S%CC&

拥塞率高的

!"#$

%：

$arameters pro'lem

*apacity

SDCCH Congestion

(nterference

0* $artition

*ommon $ro'lems

already analyzed



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2mproper setting of parameters


Analysis Of S%CC& Bloc(in)

0d!ust parameters ,random access

error level threshold2 R0*+ access

level threshold-2 &a#imum

retransmission times2 E#tend

Transmission distri'uted timeslots -=

0d!ust location update parameters=

0d!ust parameters of the dual.'and

network3

4asic measurement9 !udging reasons

for )D**+ congestion； Radio access measurement9

immediate assignment successtimes@immediate assignment

timesA&； $arameters checking9 parameters of

correlative with radio access=

ow usa'ility rate )D**+3




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2nsufficient system capacity



E#tend network capacity=

0dd )D**+=

0d!ust TF7GG、 TFG7G、 R0*+

parameters etc3 ； 0d!ust other parameters3

$erformance report9 T*+ and )D**+

'oth congested=

$erformance report9 T*+ don;t

congest 'ut )D**+ is congestedseriously=

$arameters ad!usting9 traffic hinge2

such as aviation hinge2 railway station

etc32 has lots of location updates=

)&) leap3




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2mproper :AC di!ision



0d!ust *R+； 0d!ust cell reselect parameters； 0d!ust TFG7G；

0d!ust other parameters3

$erformance report9 )D**+

congested 'adly=

4asic measurement9 percent of

location update too high= 0* partition9 'usiness area2 0*

areas are crossed 'adly=




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E&istence of interference



*heck and ad!ust fre%uency point=

)olve interferences=

0d!ust access parameters3

R0*+ level threshold is lower2 at the

same time has interference2 system

mistake for having lots of )D**+

occupation re%uests3

$erformance report9 )D**+

congested 'adly=

4asic measurement9 more useless

)D**+ access =


TC5#osition And Analy2e #ro'les with Traffic Statistics


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TC5指配问题分析#osition And Analy2e #ro'les with Traffic Statistics4 Analysis of TC& Assi)nent #ro'les TC5 Channel Analysis $rocess

Channel Occu"ation

After the syste

receives C&A99E+

!E:1I!E coand; it

will in5uire channel

resources in M#

data'ase<

TC& Channel

Allocation

BSC sends Channel

Activation FO! TC&coand to BTS， that isTC& channel allocation

atte"t< BSC receives BTS=s

feed'ac( essa)e Channel

Activation AC$; then

allocation has 'een done<

TC& Channel

Assi)nent

It is carried out

'etween BSC and MS< BTS

>ust transits coands

trans"arently< Then it is a

channel assi)nent atte"t<?hen BSC receives BTS=s

feed'ac( essa)e Esta'lish

Indication; it is considered

assi)nent is successful<

/

,



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Analysis of TC& Assi)nent #ro'les Causes of TC5 Assignment 8ailure

+ardware pro'lems： TR:、 *D/、 loose panel ca'les；

(nterference： co.channel@ ad!acent.channel interference@ e#ternal interference=

0ntenna pro'lems9 damaged antenna feeder2 uni.polarized antenna azimuth2

inconsistence 'etween down.tilt and antenna type2 high ?)WR2 crossed or

misconnected antenna feeders=

/nreasona'le parameter configuration： improper setting of +1 parameters2 TF78H

value is set too small2 inconsistence 'etween data configured at O&*R and the data

planned2 etc3=

*overage pro'lem： weak signal or uplink Idownlink im'alance =

Repeater pro'lem9 uplink@downlink interference or im'alance of uplink@downlink=

Other reasons： soft I hardware versions of the system、 signaling cooperation

'etween 4)* and &)*=



70/81

Analysis of traffic statistics


Analysis of TC& Assi)nent #ro'les


Check "hether radio parameters of the

cell is reasonableD

Check 'E+、 idle interference band le!el

inde&* decrease radio interferenceD

Check hard"are of the cellsD

Check transmission problemsD

#T analysisD

Check 'SC and base station !ersions to

a!oid unmatched !ersions leading to TC5assignment failure)

$erformance report： find out cells "ith

TC5 assignment failureD

'asic measurements： 9udge

interference band、 calldrop、 hando!er 、 uplink7 do"nlink

+6 !alueD

Alarm statistics： hard"are problems

'TS measurements： position TC5

assignment failure of carrier fre(uency

le!el 3MS： 9udge "hether carrier fre(uency

occupation is normal by occupation time

of TC5 and S#CC5D

$arameter configuration：

unreasonable dynamic S#CC5

parameter configuration)


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C f C ll %


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Cases of Call %ro" $henomenon #escription

On 7B2 &arch2 from O&*R 40& statistic2 (78 of )tation F of 4)* 8 in $0"TE network had

much more call drop rate suddenly2 with its rate more than HJ3 *all drop times increased a lot3

$roblem Analysis Through carrying out statistic on detailed performance data2 checking call drop types2 we found

radio link failure accounted for great part of call drop=

Through carrying out statistic on the interference 'and of the cell2 we found F.level or a'ove

interference 'and accounted for higher percentage=

We dou'ted first that the station had interference3 0fter checking fre%uency planning2 we found

there was no neigh'oring interference with ad!oining cells3 Through 4T) measurements2 we

found the second and third carrier fre%uency of the station had a higher failure rate

1rom alarm statistics2 this station had no hardware alarms2 no ad!acent cells missed in

configuration2 handover parameters are reasona'le3 +owever2 it;s found that the &0(Os of the

second and third TR:s are the same3

C f C ll %


73/81

Region *ell Name 4)* (D *E (D D0TET*+ in call drop

rate,J-Remark

NORT+ (78G 8 88GG

G88B.F.7B 37H

'eforeAd9ustment

G88B.F.7H H3HK

G88B.F.7 H3F

G88B.F.7L H3LH

G88B.F.F7 738F

After

Ad9ustment

G88B.K.7 83LK

G88B.K.G 83

G88B.K.F 83HB

Cases of Call %ro"

Solution

0fter ad!usting &0(O of the third carrier fre%uency from to 782 the interference

disappeared2 call drop times decreased greatly and call drop rate restored to

normal3


74/81

C f TC& & d # 'l


75/81

Cases of TC& &andover #ro'les

$roblem Analysis

Checked parameters of 'AM in

the station* and the

configuration is okD

Then checked station hard"are

and it is normalD

+esetting the station can not

sol!e the problem)

reconfigure the base station

data can not either)

8ront and back platform Z#'

files are consistent

Solution

After resetting M$* hando!er

restored to normal)

4)*No3

)(TENo3

*E

No2

0d!oining*ell *(

77787,successful

handover

outattempts to

thead!oining

cell-

7778G,successful

handover

outattempts

to thead!oining

cell-

7 FG 7 8GG HH 8

7 FG 7Other

ad!acent*ell

F K

7 FG G 8G7 788 8

7 FG GOther

ad!acent

*ell

BF L

7 FG F 8G7 H 8

7 FG FOther

ad!acent*ell

FF GL

C f TC& Bl (i


76/81

Cases of TC& Bloc(in)

$henomenon #escription On G72 Decem'er2 we carried out statistic from 40&2 and found T*+ traffic of the

third sector of No3 78B station in 4)* under i'yan network is very congested

suddenly3 T*+ congestion rate（ e#clude handover ） arrived at higher than F8J3

$roblem Analysis 4efore2 this sector wasn;t congested2 'ut this time was in sudden T*+ traffic

congestion3 0fter implementing statistic on the performance report and alarm

statistic of the surrounding cells2 we found the reason for congestion was that

No37GH station corresponding with this cell had 'roken2 thus the neigh'oring traffic

had 'een a'sor'ed 'y the third sector of No2 78B station3

Solution

0fter coordinating with the office2 commission the No37GH station in time3 Then T*+

traffic congestion of the third sector of N83 7GH had 'een cleared3


77/81

C f S%CC& Bl (i


78/81

Cases of S%CC& Bloc(in)

$henomenon #escription (n )eptem'er2 after No3B7 new station had 'een commissioned2 )D**+ channel of the third

cell congested suddenly and its congestion rate was as high as FJ3

$roblem Analysis Through analyzing the 'asic measurement of the cell2 we found the reason for )D**+

congestion in the third cell was that there e#isted a great amount of positions to 'e updated3

0fter checking plan data and 0* division2 we didn;t find unreasona'le points3 Thus we

analyzed that this new station had certain mistaken data during commissioning3

Solution

0fter checking2 we found 0* No3 of the third cell in the station is 7L2 while 0* No3 of other

two cells of the station is 7LL3 (t is confirmed that during commissioning the new station2 0*

No3 of the third cell was input 7L mistakenly3 (t should 'e 7LL3 Thus caused a great amount

of positions to 'e updated3 Through read!ustment2 )D**+ congestion rate restored to normal3

Cases of TC& Assi)nent


79/81


$henomenon #escription (n the third cell of No37 station of $+O2 its call drop rate arrives at B3LJ

2successful handover in rate is only B3FJ2 while handover out rate is L73F7J3

$roblem Analysis

TC5 assignment rate is morn than ?@* from "hich "e e&cluded the interference

problem and make sure that the cell has hard"are problems) After analyzing 'TS

measurements of the cell* "e found that TC5 assignment failure rate of the second

carrier fre(uency in the cell is !ery high* arri!ing at @) And during on-site testing*

"e found that after occupying this carrier fre(uency* the signal le!el is F@d' less

than 'CC5 carrier fre(uency le!el)

Solution

0fter changing carrier fre%uency2 each parameter restores to normal3



80/81

4)* .)(TE(D.4T)

*ell and ocation 0rea

*ell,0*.*(-

T*+ in call droprate,includehandover-

,J-

T*+ droppedcall totalnum'er

T*+ assignfailurerate,J-

+andover insuccessrate,J-

+andover outsuccessrate,J-

4sc8.)ite7.4tsF

0*788F.*(888F B3L L 7G3G B3F L73F7

After Ad9ustment

4sc8.)ite7.4tsF

0*788F.*(888F 83L G3G LG3F LG3L


A Contrast 'efore 7After ptimization


81/81

gsm traffic statistics analysis

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