1. Baseline Specifications for GSM BSS Network Performance KPIs (Call Drop Ratio on TCH)

8/9/2019 1. Baseline Specifications for GSM BSS Network Performance KPIs (Call Drop Ratio on TCH)

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Product Name Confidentiality Level

G3BSC Confidential

Product VersionTotal 24 pages

Baseline Specifications for GSM BSS

Network Performance KPIs

(Call Drop Ratio on TCH)

or internal use only

Prepare !"#!u "#en$ !C%&' ( GS&Performance )esearc# %ept* Date# 2++,-+.-2/

Re$iewe !"# Date# yyyy-mm-dd

Re$iewe !"# Date# yyyy-mm-dd

%ppro$e !"# Date# yyyy-mm-dd

H&awei Tec'noloies Co* +t%ll ri'ts reser$e


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Ta!le of Contents

, %!o&t KPI Definition

0*0 1P Name*****************************************************************************************************************************0*2 1P &eaning*************************************************************************************************************************0*3 )ecommended ormula*******************************************************************************************************

0*3*0 ormula of t#e BSC32***********************************************************************************************0*3*2 ormula of t#e BSC/+++*******************************************************************************************0*3*3 &easurement Time Points*************************************************************************************** 03

0*4 t#er %efinition &odes of t#e 1P**************************************************************************************0/0*4*0 1P %efinition of ricsson*********************************************************************************** *****0/0*4*2 1P %efinition of No5ia********************************************************************************************* 0,0*4*3 1P %efinition of Siemens**************************************************************************************** 060*4*4 1P %efinition of &otorola**************************************************************************************** 07

0*. Suggestions on 1P ptimi8ation***************************************************************************************20

- KPI Test Met'o--

. KPI Baseline --3*0 Baseline of Call %rop )atio on TC9 of t#e BSC32*************************************************************223*2 Baseline of Call %rop )atio on TC9 of t#e BSC/+++*********************************************************23

/ Constraint %nal"sis-.4*0 Test &et#od Constraints*****************************************************************************************************234*2 Test nvironment Constraints**************************************************************************************** ****234*3 1P %efinition Constraints********************************************************************************************* *****244*4 Parameter Constraints******************************************************************************************************* 244*. unction Constraints********************************************************************************************************** 2/4*/ nter-1P Constraints**********************************************************************************************************2,4*, Version Constraints************************************************************************************************************ 2,

0 Baseline Commitments-1

.*0 Baseline Commitments****************************************************************************************************** 26.*0*0 Baseline Commitments in t#e vent of Net:or5 )elocation************************************26.*0*2 Baseline Commitments in t#e vent of Ne: Net:or5 Construction*************************27.*0*3 )is5 'nalysis************************************************************************************************************27

2 KPI 3ptimi4ation Means-5


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+ist of 6i&res

6i&re ,C#annel sei8ure in t#e immediate assignment procedure****************************************03

6i&re -C#annel sei8ure in t#e assignment procedure*********************************************************03

6i&re .C#annel sei8ure in t#e internal #andover procedure of t#e BSC*****************************04

6i&re /C#annel sei8ure in t#e incoming BSC #andover procedure*************************************04


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Re$ision Histor"

DateRe$ision7ersion

C'ane Description %&t'or

2++,-.-2/ V0*+ Completed t#e initial draft* !u "#en

2++,-/-0/ V0*0 &odified t#e document according to t#e revie:comments*

!u "#en


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Baseline Specifications for GSM BSS NetworkPerformance KPIs (Call Drop Ratio on TCH)

Ke"worsCall drop ratio on TC9$ 1P

%!stract

T#is document descri;es t#e definition$ test met#od and constraints of t#e call dropratio on TC9*

%cron"ms an %!!re$iations

%!!re$iation 6&ll Spellin


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, %!o&t KPI Definition

T#e 1P is determined ;y t#e name$ meaning and definition* Because t#e BSC32 and t#e

BSC/+++ #ave difference only in t#e inde< names used in t#e specific calculation formula and donot #ave any difference in t#e measurement time points$ section 0*3=)ecommended ormula>gives t#e calculation formulas of t#e BSC32 and t#e BSC/+++* T#e ot#er contents are t#e samefor ;ot#*

T#e =current version> descri;ed #ereinafter refers to t#e follo:ing?

BSC32? G3BSC32V3++)++,C+0

BSC/+++? BSC/+++V7++)++0

,, KPI Name

Call drop ratio on TC9

,- KPI Meanin

T#e call drop ratio on TC9 reflects t#e ratio of call drops to successful TC9 sei8ures after t#eBSC successfully assigns a TC9 to t#e &S* t can ;e assessed from t:o aspects* ne is toassess t#e pro;a;ility of call drops on all esta;lis#ed TC9s in t#e cell and t#e ot#er is to assesst#e pro;a;ility of call drops on TC9s during call esta;lis#ment of t#e cell*

T#e call drop ratio on TC9 is an important inde< of t#e call #old type* t indicates t#e pro;a;ility offailure to normally end t#e conversation due to various reasons after t#e &S normally accessest#e TC9* ' too #ig# call drop ratio on TC9 :ill directly influence su;scri;ers@ feeling*

,. Recommene 6orm&la

T#e call drop ratio on TC9 is mostly o;tained t#roug# t#e traffic measurement results or t#roug#t#e drive test* T#e follo:ing formula is recommended for it?

Call drops on TC9 A Successful TC9 sei8ures*

,., 6orm&la of t'e BSC.-

Call %rop )atio on TC9 including #andover D Call %rops on TC9 E Call %rops on TC9 in Veryarly 'ssignment A Successful TC9 Sei8ures 'll F 0++

Call %rop )atio on TC9 e


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Sta;le State SeIuence rror ECall %rops due to )) N% )eceived on TC9 TC9 in Sta;leState )adio Lin5 ailure E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State9 'ccess ailure E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State &ntervention E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State )adio)esource Hnavaila;le E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le Statet#er Causes E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State )adioLin5 ailure E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State 9 'ccessailure E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State &ntervention E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State )adio)esource Hnavaila;le E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le Statet#er Causes E Call %rops due to )L N% )eceived on TC9 TC9 E Call %rops due to )LN% )eceived on TC99 TC9 E Call %rops due to ';is Terrestrial Lin5 ailure TC9 TC9 ECall %rops due to ';is Terrestrial Lin5 ailure TC99 TC9 E ailed nternal ntra-Cell9andovers Timer


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State )adio Lin5 ailure E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State9 'ccess ailure E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State &ntervention E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le State )adio)esource Hnavaila;le E Call %rops due to )) N% )eceived on TC9 TC9 in Sta;le Statet#er Causes E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State )adioLin5 ailure E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State 9 'ccessailure E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State &ntervention E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le State )adio)esource Hnavaila;le E Call %rops due to )) N% )eceived on TC99 TC9 in Sta;le Statet#er Causes E Call %rops due to )L N% )eceived on TC9 TC9 E Call %rops due to )LN% )eceived on TC99 TC9 E Call %rops due to ';is Terrestrial Lin5 ailure TC9 TC9 ECall %rops due to ';is Terrestrial Lin5 ailure TC99 TC9 E ailed nternal ntra-Cell9andovers Timer


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Cell 9andover )eIuests TC9 06++A07++-7++A6.+ - ailed ncoming


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Eutgoing


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assignment$ t#ere is slig#t difference ;et:een t#e call drop ratio including #andover of t#eBSC32 and t#at of t#e BSC/+++*

Because t#ere are fe: call drops on TC9 in very early assignment$ t#e call drop ratio on TC9including #andover #as slig#t difference from t#e call drop ratio on TC9 e


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6i&re . C#annel sei8ure in t#e internal #andover procedure of t#e BSC

6i&re / C#annel sei8ure in t#e incoming BSC #andover procedure

!#ere?

TC9-SHCCETC9-SHCC-'ETC9-SHCC-BETC9-SHCC-C? Successful TC9 sei8ures all TC9-SHCC-'? Successful TC9 sei8ures TC9-SHCC? Successful TC9 sei8ures in very early assignment

&easurement time points of t#e call drop ratio on TC9?

!#en t#e TC9 serving as t#e traffic c#annel is sei8ed$ t#e BTS sends an )))N%C'TN message to t#e BSC ;ecause of TC9 radio lin5 layer connection e


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Hpon receipt of t#e message$ t#e BSC starts t#e T)ST'BLS9 timer* T#e BSC starts tomeasure t#e call drop ratio on TC9 after t#e timer e


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!#ere?

TM%)MS? Call drop ratio on TC9 TNM%)P? T#e num;er of call drops on TC9* T#e measurement starts :#en t#e BSC sends

a CL') )HST message or receives a CL') C&&'N% message t#at carries acause value ot#er t#an =Call Control> or =9andover Success> from t#e &SC* f t#e BSC #asalready sent t#e CL') )HST message ;efore receiving t#e CL') C&&'N%message$ t#e CL') C&&'N% message :ill not ;e counted in t#e num;er of call dropson TC9*

NMC'LLS? T#e num;er of calls successfully initiated in t#e current cell* t includes t#enum;er of directed retries initiated ;y t#e current cell to ot#er cells and does not include t#enum;er of directed retries initiated ;y ot#er cells to t#e current cell*

,/,- %nal"sis

n t#e formula of ricsson$ t#e numerator also includes t#e CL') C&&'N% message t#atcarries a cause value ot#er t#an =Call Control> or =9andover Success> from t#e &SC* T#erefore$t#e numerator covers more su;-inde


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,/-- %nal"sis

n t#e formula of No5ia$ t#e system starts measuring t#e su;-inde


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of successful incoming cell #andovers$ t#e denominator of Siemens formula 2 is eIuivalent tot#e denominator of our formula for t#e call drop ratio on TC9 e


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Net:or5 level?

!#ere?

%)PMC'LLM)'T? Call drop ratio on TC9 )MLSSSMTC9? Call drops on TC9 due to ) reasons$ including all t#e call drops in t#e

sta;le state due to ) reasons NT)'MCLLM9NT)'MCLLM9MLST&SO? Call drops in t#e intra-cell #andover

procedure HTMNT)'MBSSM9HTMNT)'MBSSM9MLST&SO? Call drops in t#e outgoing

internal inter-cell #andover procedure HTMNT)MBSSM9HTMNT)MBSSM9MLST&SO? Call drops in t#e outgoing

e


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,//. S&!stit&te 6orm&la of H&awei

!#en comparing our call drop ratio on TC9 :it# t#at of &otorola$ :e cannot determine :#ic#su;stitute formula s#ould ;e used ;ecause :e cannot determine t#e specific measurementmet#od of &otorola for t#e call drop ratio on TC9* !e must determine t#e formula to ;e usedaccording to t#e actual formula used for t#e net:or5*

!#en comparing our call drop ratio on TC9 :it# t#at of &otorola for t#e net:or5s of mo;ilecommunication companies$ :e can use t#e follo:ing formula for t#e cell-level 1P? Call drops onTC9 A Successful TC9 sei8ures all J Successful TC9 sei8ures in very early assignment*

or t#e BSC-level 1P$ :e can use t#is formula? Call drops on TC9 A Successful TC9 sei8uresall J Successful TC9 sei8ures in very early assignment - Successful internal inter-cell#andovers of t#e BSC*

or t#e net:or5-level 1P$ :e can use t#e recommended formula*

T#e su;stitute formula s#ould ;e consistent :it# t#e formula of &otorola for t#e call drop ratio onTC9 for t#e net:or5s of mo;ile communication companies*

,0 S&estions on KPI 3ptimi4ation

'fter comparing our measurement met#od :it# t#e measurement met#ods of competitors for t#ecall drop ratio on TC9$ :e recommend t#at t#e call drops in t#e incoming BSC #andoverprocedure ;e e and 0*4=t#er%efinition &odes of t#e 1P> for details$ and t#e 1P may vary :it# t#e specific calculationformula* T#erefore$ register as detailed su;-inde


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Note? Because different competitors #ave different measurement met#ods$ t#e call drops on TC9do not necessarily correspond one to one :it# t#e CL') )HST messages* T#is met#odonly provides a :ay for us to ma5e preliminary udgment* T#e difference ;et:een t#e t:o valuesdoes not necessarily mean t#at t#e traffic statistics are falsified*

. KPI Baseline

., Baseline of Call Drop Ratio on TCH of t'e BSC.-

KPI NameClass %Network

Class BNetwork

Class CNetwork

Class DNetwork

Call drop ratio on TC9including #andover

+*24 +*.0 +*/6 +*,,

Call drop ratio on TC9e*

.- Baseline of Call Drop Ratio on TCH of t'e BSC2888

KPI NameClass %Network

Class BNetwork

Class CNetwork

Class DNetwork

Call drop ratio on TC9including #andover

+*24 +*.0 +*/6 +*,,

Call drop ratio on TC9e*

Because at present t#ere are fe: BSC/+++ sites$ t#e ;aseline of t#e BSC32 is used as t#ereference ;aseline* T#e relevant data :ill ;e updated later along :it# t#e increase of sites*

/ Constraint %nal"sis

/, Test Met'o Constraints

/- Test 9n$ironment Constraints

nsure t#at t#e net:or5 optimi8ation #as ;een completed and t#at t#ere is no engineeringconstruction error ;efore t#e test*


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T#e committed ;aseline values cannot ;e guaranteed in t#e follo:ing cases :#en t#e a;oveprereIuisite is satisfied?

Test 9n$ironment Pro!lem Description

Coverage

T#ere are pro;lems suc# as ;lind spots$ lo: coverage level or crosscoverage in t#e test environment$ and suc# pro;lems cannot ;e

solved ;y net:or5 optimi8ation*T#ere is o;vious cross coverage in t#e test environment*

nterference

T#ere is inevita;le interference from ot#er net:or5s or repeaterstations in t#e test environment$ or #ig# freIuency reuse due tofreIuency resource s#ortage$ :#ic# inevita;ly causes severe internalinterference to t#e net:or5*

TransmissionPoor Iuality of transmission lines suc# as ';is interface lin5s and 'interface lin5s or insta;le transmission lin5s due to various reasons int#e test environment*

IuipmentPlenty of terrestrial resources are unavaila;le or a lot of eIuipmentfails during t#e test*

'ntenna and feedersystem

T#e coverage is poor ;ecause of different pitc# angles of t#e t:oantennas :#en single-polari8ed antenna is used*

T#e voltage standing :ave ratio !S!) is #ig# due to factors of t#efeeder itself* T#is :ill lo:er t#e transmit po:er and receivingsensitivity$ and cause poor coverage and call drops*

TrafficT#e actual net:or5 traffic is unevenly distri;uted in t#e testenvironment*

/. KPI Definition Constraints

Because competitors and operators may #ave different reIuirements for t#e calculation formulaof t#e call drop ratio on TC9 from us$ :e s#ould carefully analy8e t#e formula differences duringt#e ;id ans:ering process and give an analysis of t#e possi;le impact of suc# differences on t#ecall drop ratio on TC9* )efer to sections 0*3=)ecommended ormula> and 0*4=t#er %efinition&odes of t#e 1P> for details*

// Parameter Constraints

!#et#er t#e relevant parameter settings of t#e call drop ratio on TC9 are reasona;le :ill directlyinfluence t#e net:or5 inde


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Parameter Confi&ration Re:&irements

System messageparameter ta;le? )adio

lin5 invalidity counter

f t#e set value is too small$ call drops :ill occur :#en t#e )< level oft#e &S suddenly fades a lot due to reasons suc# as geograp#icalconditions* f t#e set value is too large$ t#e net:or5 :ill ;e una;le torelease relevant resources until t#e radio lin5 times out$ even if t#e

speec# Iuality is far more unaccepta;le* 's a result$ t#e freIuencyutili8ation :ill ;e lo:ered* !e can set t#is counter to a larger value fort#e ;order areas :it# little traffic and set it to a smaller value for t#eareas :it# #ig# traffic during t#e parameter setting*

Cell attri;ute ta;le?S'CC9 multiframecount

ts function is t#e same as t#e radio lin5 invalidity counter*

System messageparameter ta;le? &Sminimum )< level$)'C9 minimum )

Documents

1. Baseline Specifications for GSM BSS Network Performance KPIs (Call Drop Ratio on TCH)