Performance KPI’s Optimization Tips

8/18/2019 Performance KPI’s Optimization Tips

1/17

3G Optimization Basics


2/17

Optimization Tips

• Retainability

• Accessibility

• IRAT Failure• UL RSSI Causes


3/17

Check neighbor cell

availability

Add suggested

Neighbors with

WNCS/GPEH/rive !est

data

Analy"e e#isting

neighbors with $G%$G

cell relation re&ort

Analy"e cell coverage by

'( Planning tool /rive

!est data/P'ACH Plots

own tilts or other

&hysical o&ti)i"ation

Check HW Alar)s

Check !* Errors

Check Cell

Availability

eter)ine i+ the

issue a++ects only

one cell or a ',S or

cluster

-eri+y +or SC

Clashes

.nvestigating the E

!#Pwr by using rive

test data or W0''

Check &ara)eter +or

E !#Pwr 1 )a#Sir

Analy"e cell

coverage by '(

Planning tool or

rive test data

se o+ GPEH to

deter)ine the

nu)ber o+ Event 2a

or nu)ber o+ Event

3d

Check Cells doe

'SS. .ssues

.denti+y the +ailing

&hase4

Audit the E#ternal

GS0 Cell 05 with

latest 3G du)&

GS0 coveragearea veri+ication

+or .'A!

neighbors

'e%&rioriti"ation

the neighbor list

based on usage

Check down switch

counter +or

congestion reason4

.nvestigate the ''C

Access +ailure due to

lack o+ 6 &ower 1

codes

Per+or) analysis o+coverage area and

reduce overshooting

-eri+y CE usage and

HW allocation and

di)ensioning

!rans&ort .ssue

',S / 'NC HW

issue

'( issues outside o+

available counters

E issues

Missin !ei"bour So#t $an%o&er Uplin' Sync IRAT Conestion Ot"ers

CS/PS

Retainability

Retainability


4/17

Retainability(Missin !ei"bor

• Drops due to Missing Neighbors

• Counter) pmNoSysRelSpeechNeighbr

• Suestions)

*+ Run ,!CS an% c"ec' Missin !ei"bors+ C"ec' inter(site %istance to %etermine i#t"ey nee% to be a%%e%+ -.rioritize missin nei"bors in t"e or%er o# / o# %rops0 /o# e&ents0 %istance0 a&erae RSC.12c1!o

4+ C"ec' .RAC$ 5elay to assess i# it is o&ers"ootin+

3+ C"ec' nei"bor cell a&ailability+ I# any o# t"e nei"bor cell is %o6n0 it can causemissin nei"bor %rops+


5/17

$i" number o# 5rops %ue toSo$o

Aremissin

!br %ropsalso "i"

I%enti#ymissin

!brs6it"

,!CS 7a%%

C"ec'S$O

Success

rate per!br

relation

8es

!o

!o

Identify somerelations withhigh SHO failrate

Is it Inter(R!C relation9C"ec' Iur 5e:nitions 7

in&estiate ot"errelations o&er same

Iur+

Is !br site "a&in $,issues0 UL RSSI0orConestion %ue to

Trasnport0p6r or ot"erresources+ Fi; nbr site

C"ec' i# Co&eraeo&erlap is su Taret

cellname

8es

C"ec' #or SCCollisions+

5elete an% re(%e:ne

t"e issue coul% be 6it"Source cell+C"ec'

a%mission controlparameters suc"

p6rA%m0 5LCo%eA%m0UL15L $,A%m to see i#

t"ere is su


6/17

$i" number o# 5rops %ue toUL Sync

Are t"ere%rops %ueto missinnbr1S$O

also

Is cello&ers"ooti

n

Other possible issues:• C"ec' #or $, #aults esp RA?boar%+•C"ec' #or Transport issues-conestion

!o

8es

Use comp mo%e statsto c"ec' i# CM usae is"i"+ @eri#y i# enou"

IRAT relations are%e:ne%+

!brin site mi"t beo&ers"ootin+ Use ,!CS to

i%enti#y boomers an% controlpollution

Impro&e 2c1!o in t"eco&erae area byusin %o6nTilts or

C.IC$ c"anes

Resol&e missin

nbrs an% S$O %rops

Is 2c1!o incells

co&eraearea oo%

-#rom,MRR

.ossible e;ternalinter#erence+ C"ec' UL

RSSI

Is cell inarea 6it"oo% 3G

site%ensity9

Re%uce 4% T"res"ol%sto allo6 IRAT uic'ly

be#ore %rop

3G co&erae "ole+Upilt or increase

C.IC$+ @eri#y nbr site#aults+

8es

!o

Increase minp6rma;+2nsure cell is not

po6er(coneste% -Usebusy "our stats

Increase minp6rRl+2nsure cell is not

po6er(coneste% -Usebusy "our stats

Increase rlFailureT 7nOutsyncIn%+

8es

I# t"e RF ser&in area"as Su%%en 2c1!o

c"anes-tunnels0bri%es

Increase -or %ecreaseIn%i&i%ual o=set toimpro&e S$O area

!o

Retainability(Flo6 C"art(UL S8!C

8es


7/17

Retainability %ue to speec"conestion

• Drops due to Speech Congestion

• Counter) pmNoOfermSpeechCong

T"is counter is Incremente% by one 6"en t"e speec" call release is %ue toconestion+ T"e connection is terminate% by R!C+

• Suestions)*+ C"ec' a%mission counters-Lac'%lCo%e0 lac'%lp6r0 UL15L$6A%m on RAB

establis"ment to :n% out t"e resource bottlenec'+4+ C"ec' #or M.Loa%+ -Suest temporary tra


8/17

Retainability(5rops %ue to Ot"ers

• .I Formula)

Drop Due to Other ! pmNoSystemRabReleaseSpeech "pmNoSysRelSpeech#lSynch " pmNoSysRelSpeechSoHo $pmNoOfermSpeechCong

Basically all ot"er speec" %rops 6"ic" 6ere not pee% in any o# t"e speec" %ropcounters %escribe% in t"e pre&ious sli%es+

• Suestions)*+ Resol&e missin nbrs0 So$o0 UL sync issues i# any be#ore Hot"er %rops4+ C"ec' Alarms1T*1UL RSSI1$,1@S,R1M.Loa% #or t"e cell+3+ C"ec' ,MRR an% .ropaation 5elay to impro&e ra%io con%ition an% co&erae

rane+E+ Assess t"e terrain pro:le an% see i# tilt can be a%Juste%++ C"ec' Iub Conestions+K+ C"ec' S$O1IRAT1IF$O #ailure rates+ Optimize t"e respecti&e -S$O1IRAT1IF$O

nbr list+ Trial "otype an% A%Just 4% t"res"ol%s -used%re&hresh'dRscp0

used%re&hresh'd(c)No i# co&erae is 6ea' in t"e area++ C"ec' #or RA?1T? boar% errors0 may reuire a restart+N+ C"ec' Scramblin Co%e Collision+*+ C"ec' C.IC$ .o6er 6it" t"e maJor nei"bors+ eep t"e %elta small to maintain

UL balance in S$O bor%er+ C.IC$ .o6er s"oul% be bet6een (*P o#ma;T;.6r+

**+ Restart t"e site i# all t"e abo&e "as been c"ec'e% an% still cannot :n% out t"e

problem+*4+ Usually %rops %ue to ot"ers are ra%io relate%-RU1CBU1FU+ A site restart or $,

re lacement mi "t be nee%e%+


9/17

IRAT Failure

I%enti#y t"e p"ase in 6"ic" t"e #ailures are occurrin+

IRAT .reparation ."ase• GSM Ra%io Conestion• IMT Trun' Conestion bet6een GSM 7 UMTS S6itc" -!5R

uery coul% be use%• UMTS(GSM !br %e:nition "as incorrect &alues -BCC$0LAC0 CI50

BSIC0 etc

IRAT 2;ecution ."ase• Co(C"annel GSM BCC$•

.oor GSM Uplin' con%ition

IRAT Con:rmation ."ase• Typically poor RF con%itions on bot" UMTS 7 GSM


10/17

CS IRAT "an%o&er FLo6c"art


11/17

UL RSSI 7 .ossible Causees

oo high #* RSSI +,$-. dbm/ can be caused by:

*+ 2;ternal sources o# uplin' inter#erence4+ Inter(mo% pro%uct -antenna #aults3+ Incorrect plumbinE+ .arameter TMA ulGain settin %oes not matc" t"e real TMA ain -Compare AMOS 6it" RF5S+ Faulty %e&ices alon t"e R; pat"

Loose Connectors

Ti"t Cable Ben%s

$i" UL RSSI cause% by e;ternal inter#erence "as sini:cant impact on UL capacity an% co&eraeo# a cell+

oo *ow #* RSSI +0$11. dbm/ can be caused by:

*+ Mostly %ue to TMA not po6ere% up an% incorrect TMA settins

4+ Incorrect plumbin Ba% Connectors0Cables etc

2hat is #* RSSI3• Recei&e% Sinal Strent" In%icator o# t"e total 6i%eban% recei&e% po6er 6it"in t"e

entire c"annel ban%6i%t"• !ote t"at RSSI %oes not %istinuis" bet6een o6n0 ot"er0 or any ot"er un6ante%internal or e;ternal inter#erence

How is #* RSSI measured in the (ricsson system3• T"e RSSI is measure% e&ery * ms+ An a&erae &alue is t"en calculate% e&ery secon%

an% store% as a .5F step rane0 K lon -(** to (K %Bm0 6it" t"e resolutions +%Bm an% %Bm+

• Counter Hpma&eraeRSSI0 MO Class HCarrier an% incremente% on t"e RBS le&el


12/17

CS/PS Accessibility

(Ericsson Classification)

RRC RAB

ccessity


13/17

M. Loa% A%min Control License !o%e Bloc'in Transport Bloc'in

•C"ec' M. loa%#or Main Rac's 12;tension SubRac's $i"99

•C"ec' #or Core!et6or' -Callser&ers 1 SGS!

outaes 0a=ectsall cells in R!C+

•Re("ome Sites

• C"ec' .arametersettins #or)

• a Fee%erlent"1TMA

• b A%m Control• c C"ec' a&ailableresources -5o6nlin'

T; po6er0

C"annelizationco%es+T"is is lo6

possibility since 0att"is stae0 resourcesreuire% are muc"lo6er t"an at RAB

stae+

•RBS speci:cparameters

•@eri#y 1correctin%i&i%ual license%capacity le&els #ort"e no%e+ -&iaAMOS

•C"ec' C"annelelements usaetren%s

•C"ec' #or no%econ:urationerror1mismatc"0no%e limitationsor transportnet6or' layerser&iceuna&ailability+

•C"ec' #orconestion onuser plane-AAL41 controlplane -UniSaal1SCT. #or IuBresources+• 2;pan% T!

ban%6i%t"

•C"ec' IuCs 1 Iu.ssucc rate0 a=ectsall cells in R!C

CS)4S 5ccessibility

+RRC/

$ar%6are1Antena alarms0

@S,R

RRC Succ rate coul% be lo6 %ue to RF relate% issuesalso+-.oor RF in RAC$0 FAC$ In&estiate t"e RF usin,MRR an% trial ma;#ac"*po6er an%constant@alueCprac"

RRC


14/17

Congestion !o%e Bloc'in Transport Bloc'in

C"ec' #or no%econ:urationerror0 no%e

limitations ortransportnet6or' layerser&iceuna&ailability+

•C"ec' #or conestion on userplane -AAL41 control plane-UniSaal 1SCT. #or IuB resources+• 2;pan% T! ban%6i%t" -a%% T*s0%e:ne more @c

•C"ec' T* 2rrors•C"ec' Loc'e% T*s

•C"ec' Iub1T5 -@c1@p Mismatc"es•S"are Tra


15/17

Congestion

CS1.S Accessibility

-RAB

AS2 $ar%6are Resource Connection Limit5L .o6er Co%e

C"ec' i# Ma;imum Transmission .o6er isaline% 6it"Ma;5lCapability C"ec' Ma;imum

Transmission .o6er an%C.IC$ ratio

Increase .6rA%m0Re%uce .6rO=set 2;plore IFLS 6it"ot"er Carrier 2nable or Increase5irecte% Retry to GSM Re%uces#*KA%m1s#A%mConsi%er increasin

po6er license• A%% anot"er Carrier

C"ec' %lCo%eA%m&alues i# a%Justmentis still possibleRe%uce 3E' Userson 5L -s#A%m

Re%uce $S(.5SC$Co%esRe%uce $S(SCC$Co%es

C"ec' Loc'e% T?1RA?Boar%sC"ec' "anin C2-restartC"ec' $S12UL resourceallocation0ul1%l$6A%m

parameter in Iublin'Re%uceeulSer&in1!onSer&inA%m

A%%0Replace RA?1T?Boar%s

@eri#y settins #orH%lAS2A%m0UlAseA%mC"ec' #or RNNtra


16/17

$ar%6are Fault

2scalate2scalate

Restart Boar%

Col% Restart !o%e

@eri#y S, on no%e-Utran Report1OSSSMO

S6ap Car%s1Boar%s

ReplaceCar%s1Boar%s

IncorrectAttenuation1Losses

TMA UL Gain.arameter C"ec'

@eri#y RF5S

2;ternalInter#erence-UL RSSIproblem e&en %urino=(pea' "ours

CS1.S Accessibility-RRC1RAB

2rrors1Cras"esAlarms

RSSI T* 2rrors

(RRC1RAB


17/17

Accessibility1Bloc' Reasons(Summary

• Common Failure Reasons

7 Lac' o# 5L .o6er

7 Lac' o# 5L Co%e

7 Lac' o# UL15L $ar%6are Resource

7 2;cee% Connection Limits -#or .S

7 Iub Conestions

7 UL RSSI 7 $, or T* Faults

7 !ei"bor site1cell %o6n

• A%mission Control ( Set o# rules t"at %etermines 6"et"er a U2 is

rante% access on ma'in a connection reuest+ A%mission controlis also use% 6"en a%%in a RAB 0 or a ne6 RL &ia S$O or ups6itc"

o# ser&ices

Documents

Performance KPI’s Optimization Tips