HO Process&Optimization

7/23/2019 HO Process&Optimization

1/34

1 NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Process

HO parameters and optimization reated toHO process in !"M net#or$

No$ia Net#or$s


2/34

% NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Process 1/2

Hando'er decisions( made )* ++ Mana,ement in -"( are )ased on temeasurement resuts reported )* te M" / -T"( parameter sets 0or eacce and a,oritms. Tar,et ce e'auation is aso one part o0 teando'er process. Hando'ers are tri,,ered o )* tresod comparisonor )* periodic comparison.

Tar,et ce e'auation is made in ++ Mana,ement in -" and its purposeis to 2nd te )est ce 0or ando'er. Te e'auation on te pre0erred ist o0te tar,et ces is )ased on3

Te radio in$ measurements Tresod comparison

Te priorit* e'es o0 te nei,)ourin, ces

Te oad o0 te nei,)ourin, ces #ic )eon, to te same -" as teser'in, ce.

+4 e'e comparison 5 i0 it is needed

Te -T" sends te ist o0 )est candidates to te -". 6irst te -"de2nes and seects tose ces( #ic meet te re7uirements 0or teradio in$ properties. ++ Mana,ement can ande up to 8% )estcandidates 0or tar,et ce e'auation.


3/34


Handover Process 2/2

-"

Eq. 1or

Eq. 1'

Adj1..Adj2.

Adj3.--------------------------------------------------------Adj32

Adj1Adj3------------------Adjn

Eq.2or

Eq.2'

Target Cell Evaluation

Cell ranked according to priority/load

Adj1Adj3-------Adji.

oad in!or"ation!ro" t#e $$"anage"ent


4/34


HO&PC Diagram

%

1

2

3

&

(

)

-11% -1% -1%% -* -*% -+ -+% -) -)% -( -(% - -%

PcUpperThresholdQualUL/DL

HoThresholdQualUL/DL

Power decrease

Power increase

Noactionneeded

Interference HoQuality Ho

LevHo

PcLevUpperThresholdLevUL/DL

HoThresholdLevD

PcLowerThresholdLevUL/DL

HoThresholdInterferenceUL/DL

PcLowerThresholdQualUL/DL

HoThresholdLevUL (if diversity gain

!"Lev#in$ell(n

!"Lev%cc#in

Power increase


5/34: NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Priority

Hando'er priorit*

1. ;pin$ and do#nin$ Inter0erence%. ;pin$ 7uait*8. Do#nin$ 7uait*

9. ;pin$ e'e:. Do#nin$ e'e. "o# mo'in, M"?. -etter ce i.e. Periodic cec$ @Po#er -ud,et HO or ;m)rea H

1B. P3 Co#er 7uait*/e'e tresods @;C/DC11. P3 ;pper 7uait*/e'e tresods @;C/DC


6/34< NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Types 1/2

Intra e HO

Hando'er in same T+ )et#een dierent timesots ontroed )* -"

Intra "ite HO Hando'er )et#een dierent sectors in same site ontroed )* -"

Inter "ite HO Hando'er )et#een sectors o0 dierent sites ontroed )* -"

Inter -" HO Hando'er )et#een sectors o0 dierent sites and dierent -"s ontroed )* M"

Inter "*stem HO Hando'er )et#een t#o M"s ontroed )* M"


7/34= NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Types 2/2

target

MSC 1

MSC 2

MSC controlled

BSC 1

outgoing

intra

cell inter BSC source

BSC 2incoming

intercell

MSC controlled


8/34> NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Syncroni!ation

Site "

Site B

"*ncronised HO )et#een co-6 ces

Nons*ncronised HO )et#een dierent sites


9/34? NOKIA HO Process&Optimization.PPT/ DATE / MPu

HO "lgorit#ms

$%uation 1AFG+CEFGNECC@n r'(evMinCell)n* Ma4 @B( AA J msT'P+rMa')n* P P J dependin, on M" assmar$

$%uation 2

P-!T #oMarginPB,T)n* #ere

P-!T J ))msT'P+rMa' msT'P+rMa')n**@AFG+CEFGDCGHO

AFG+CEFGNECC@n

@-tsT'P+rMa' -T"GTP+$%uation 2.@I0 ena-leHoMargin(evual J LP-!T #oMargin(ev/ual)n* #ereP-!T J @AFG+CEFGNECC@n AFG+CEFGDCGHO@-tsT'P+rMa'-T"GTP+AFG+CEFGNECC@n3 A'era,ed recei'in, e'es o0 adacent ces

AFG+CEFGDCGHO3 A'era,ed recei'in, e'e o0 ser'in, ce)tsT4P#rMa43 Transmittin, po#er e'e o0 ser'in, ce


10/341B NOKIA HO Process&Optimization.PPT/ DATE / MPu

Po+er Budget Handover 1/2 Tri,,er

Periodic ec$ @ #oPeriodPB,T

andidate "eection E7uation 1 &% used Priorit* and Coad onsidered

T*pica* used )et#een ces o0 te same Ca*er

Parameters Faue HOPeriodPB,T 0 3 S"CCH periods ena-leP+rBudgetHandover 4 / 5 r'(evMinCell)n* 110 67 dBm msT'P+rMa')n* 0 30 dBm #oMarginPB,T)n* 0 3 dBm


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Po+er Budget Handovers 2/2

P-!T J @@msT'P+rMa' msT'P+rMa')n @AFG+CEFGDCGHOAFG+CEFGNEC

@-tsT'P+rMa' -T"GTP+

P-!T J @@8Bd-m8Bd-m@?B >B@9%d-m9%d-m J 1B d-

1B d- < d- OK

AFG+CEFGNECC@n r'(evMinCell)n* Ma4 @B( msT'P+rMa')n* msT'P+r

>B d-m ?? d-m @8B d-m 8B d-m J ?? d-m

1.

%.

AFG+CEFGDCGHO J ?B d-mmsT'P+rMa'J 8B d-m @J 1-tsT'P+rMa' J 9% d-m @J 1< -T"GTGP+ J 9% d-m J @1< #oMarginPB,T)n*J < d-

"er'in, e3 -est Adacent e3

AFG+CEFGNECC@n J >B d-mr'(evMinCell)n*J ?? d-mmsT'P+rMa')n*J 8B d-m @J 1-tsT'P+rMa'J 9% d-m @J 1<


12/34

1% NOKIA HO Process&Optimization.PPT/ DATE / MPu

(evel Handover 1/2

Tri,,erTresod omparison @ #oT#res#olds(ev8(/D()p' n'

andidate "eection E7uation 1 used E7uation % used i0 ena-leHoMargin(evual J N E7uation % #it#oMargin(evused i0ena-leHoMargin(evual J L Priorit* and Coad onsidered #itin te same -"

Parameters HOT#res#old(ev8(/D( 110 67 dBm

p' 1 32 n' 1 32

r'(evMinCell)n* 110 67 dBm msT'P+rMa')n* 0 30 dBm

#oMargin(ev)n* 26 26 dB


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(evel Handover 2/2

E7uations 1 and % are used i0 parameter ena-leHoMargin(evual is set QLesR

% d-

#oMargin(evJ 9 d-

Tri,,er 0or Hando'er due to Ce'e

A

-

J e - is not seected as candidate 0orHO due to e'e since %d- S 9 d-

Tresod @Ce'?: d-m


14/34


uality Handover 1/2

Tri,,erTresod omparison @ #oT#res#oldsual8(/D()p' n'

andidate "eection E7uation 1 used E7uation % used i0 ena-leHoMargin(evual J N E7uation % #it#oMarginualused i0ena-leHoMargin(evual J L Priorit* and Coad onsidered

Parameters Faue HOT#res#oldual8(/D( 0 7

p' 1 32 n' 1 32

r'(evMinCell)n* 100 67 dBm msT'P+rMa')n* 0 30 dBm

#oMarginual)n* 26 26 dB


15/34

1: NOKIA HO Process&Optimization.PPT/ DATE / MPu

uality Handover 2/2

E7uations 1 and % are used i0 parameter ena-leHoMargin(evual is set QLesR

% d-

#oMarginualJ B d-

Tri,,er 0or Hando'er HO due to uait*

A

-

J e - is seected as potentia candidate 0or HO due to uait* since % d- B d-


16/34

1< NOKIA HO Process&Optimization.PPT/ DATE / MPu

Signal uality in ,SM

+ uait* @+;AC parameter

+;AC casses B ... =,it error rate beforeall decoding/ correction

$0A ean E$ E$ range

cla 45 !ro"... to

% %61& 7 %6241 %62+ %62 ... %6& 4

2 %6) %6& ... %6+ 4

3 1613 %6+ ... 16( 4

& 262( 16( ... 362 4

&63 362 ... (6& 4

( *6% (6& ... 126+ 4) 1+61 8 126+ 4

ua,le ignal

unua,le

ignal

good

accepta,le


17/34

1= NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Due To 9nter:erence

Tri,,er 3 Tresod omparisonTresod omparison 0or uait* @ #oT#res#oldsual8(/D()p' n'*

Tresod omparison 0or Ce'e @ #oT#res#olds9nter:erence8(/D()p' n'* andidate "eection

Priorit* 0or Intere / Intrace HO seected at -" independent* 0or ;C / DC Priorit* Intere HO

uait* HO i0 an* candidate I0 not Intrae HO

Priorit* Intrae HO

Parameters Faue #oT#res#old9nter:erence8(/D( 110 67 dBm

p' 1 32 n' 1 32

ena-le9ntraHo9nter:8(/D( 4 / 5 #oPre:erenceOrder9nter:8(/D( 95T$; / 95T;"


18/34

1> NOKIA HO Process&Optimization.PPT/ DATE / MPu

9mperative Handovers

Imperati'e Hando'ers Hando'er due to Distance Order to empt* ce( 0rom NM" Directed +etr* or ID+ +apid 6ied Drop


19/34

1? NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Due To Distance

Distance Process msDistanceBe#aviour@B(1..


20/34

%B NOKIA HO Process&Optimization.PPT/ DATE / MPu

Directed ;etry

Directed +etr* Directed retr* is ando'er 0rom ser'in, ce "DH to an

adacent ce TH durin, ca setup ;sed #en TH con,estion is disa)in, TH assi,nment Ena)ed )* parameter dr9n8se

Parameters Faue dr9n8se 4 / 5

DrT#res#old 110 67 dBm

Handover Due To ;apid >ield


21/34

%1 NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover Due To ;apid >ieldDrop

Tri,,erTresod omparison @ HoT#res#old;apid(ev8l@p'

+4GCe'G;C @Not a'era,ed / On* ;C andidate "eection

On* ained adacent ce E7uation 1 on* / no priorit*

MutiCa*ered Net#or$

Parameters Faue

HOT#res#old(ev8(:or;apid>ieldDrop 110 67 HOT#res#old;apid(ev815 0 32 c#ained"d?acentCell 4 / 5


22/34

%% NOKIA HO Process&Optimization.PPT/ DATE / MPu

HO Parameters 1/

9ntervalsmin9ntBet+eenHo;eg

Pre'ents repetiti'e ando'ers 0or te same M" #it a timer tat setste minimum inter'a )et#een ando'ers

Min9ntBet+een8nsuccHo"ttemptIndicates te minimum time tat M" must #ait a0ter ando'erattempt 0ais and )e0ore it can tr* a ando'er attempt a,ain


23/34


HO Parameters 2/

;adio ;esource Parameters

-ts(oadT#res#oldec$s te oad tresod ratio o0 candidate ces

#o(evPriority

De2nes te priorit* e'e o0 an adacent ce to account 0or ocation

#o(oad>actor

De2nes o# muc te priorit* e'e #i )e decreased #en te oad

tresod is e4ceeded

msSpeedt#res#old5'/P'

ompares speed tresod 'aues


24/34


HO Parameters 3/

Po+er Budget Parameters

Po+er -udget #andover procedure ensures t#at t#e MS is al+ays#anded over to t#e cell +it# t#e minimum pat# loss

e'en tou, te 7uait* and te e'e tresods ma* not a'e )eene4ceeded

$na-lePo+erBudgetHO

Indicates i0 po#er )ud,et is used as a criterion 0or a ando'er

HoPeriodPB,T

-" e'auates adacent ces tar,et ce 0or te ando'er at e'er*de2ned "AH inter'a


25/34

%: NOKIA HO Process&Optimization.PPT/ DATE / MPu

HO Parameters 6/

uality (evel Parameters

HoT#res#oldsual8(/D(compares te a'era,ed 'aues o0 "@;A8"( or"@;A($@

;'ual is te tresod e'e 0or ando'er.

The range is 12.8% bit error rate

5'is te tota num)er o0 a'era,es to )e ta$en into account )e0oredecision is possi)e.

The range varies from 1 to 32P'is te num)er o0 a'era,es out o0 tota a'era,es tat a'e to )e,reater tan or e7ua to te tresod )e0ore a ando'er is possi)e.

The range varies from 1 to 32

O


26/34

%< NOKIA HO Process&Optimization.PPT/ DATE / MPu

HO Parametrs =/

MS to BTS Distance

en distance is te reason 0or te ando'er re7uestmsDistanceBe#aviour contros te )ea'iour o0 te M"

Tere are tree aternati'es in #ic te Mo)ie #i act in te case o0 tisImperati'e Hando'er3

It #i reease te ca immediate*

Tr* a 1 to


27/34

%= NOKIA HO Process&Optimization.PPT/ DATE / MPu

HO Parametrs /

S#aring t#e (oadT#e MSC may re%uest t#e BSC to per:orm a specied num-er o:

#andovers :rom one specied cell :or load s#aringIt is possi)e to ando'er to U#orse ces

T#e eld strengt# in t#e ad?acent cell #as to -e a-ove t+o parameterr'(evMinCelltr#oTarget(evel

The target cells are only ranked according to radio link roerties

riority levels are not !sedThe feat!re is disabled by setting the val!e to "not !sed"

5 t D t ; t


28/34

%> NOKIA HO Process&Optimization.PPT/ DATE / MPu

5et+or Doctor ;eports

;se0u Hando'er Net#or$ Doctor reports 0or HO optimization andana*sis

1:B( es a'in, i, HO 0aiure ratio 1:8( Adacencies a'in, i, HO 0aiure ratio 1:9( Hando'er cause distri)ution 1:=( es a'in, i, HO att./ca ratio 1:>( Intra -"" ando'er o)ser'ation statistics

Oter ND reports 0or HO ana*sis&studies B


29/34

%? NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover >lo+c#arts

Handover >ailure

New Channel, New Cell

H"5DO@$; CMD

"CT9@$ C"((

MS 5$TDO;E

H"5DO@$; >"9(

"CT9@$ C"((

Old C#annel< Old Cell


Timer T3126 e'piry or;adio (in >ailure

S i d H d


30/34

8B NOKIA HO Process&Optimization.PPT/ DATE / MPu

Syncroni!ed Handover

5e+ C#annel< 5e+ Cell

"CT9@$ C"((

H"5DO CMD

H"5DO "CCH"5DO "CC

H"5DO "CC

H"5DO "CC

H"5DO COM

"CT9@$ C"((

MS5$TO;E


Serving BTS 5eig#-or BTS

)>"CCH*

)>"CCH*

)>"CCH*

)>"CCH*

)>"CCH*

)>"CCH*

5on S ncroni ed Hando er


31/34


5onSyncroni!ed Handover

5e+ C#annel< 5e+ Cell

MS5$TO;E

"CT9@$ C"((

H"5DO CMD

H"5DO "CC F

H"5DO "CC

PH4S 95>O

PH4S 95>O

H"5DO COM

"CT9@$ C"((


N*1

Serving BTS Serving BTS

T3126)in MS*

Handover "nalysis


32/34

8% NOKIA HO Process&Optimization.PPT/ DATE / MPu

Handover "nalysis

ic$ ere to ,o HO ana*sis Vo#cart

ompare Net#or$ on2,uration a,ainst Net#or$ Desi,n

Adacencies to None4istin, es

Nons*mmetrica Adacencies

Adacent e #it same or adacent 6re7uenc*

"*ncronised HO Adacenc* Discrepancies

-T" De0aut Parameter Audit

Drive Test "nalysis 1/2
http://ho%20analysis%20chart.ppt/#Handover%20Priorityhttp://ho%20analysis%20chart.ppt/#Handover%20Priority


33/34



I0 dri'e test data a'aia)e 6ind a te HO6 0aiures usin, ana*sis toos "tud* reason 0or HO 0aiure usin,

!rapica data pro'ided )* ana*sis too Ca*er 8 messa,es pro'ided )* ana*sis too NM" data @ND reports

ommon reasons 0or HO 0aiures Hando'er e4ecuted too ate @source ce 7uait* or inter0erence aread* too

)ad

HOP-!T mar,in( HOCe'e( HO #indo# a'era,in, size Tar,et ce 7uait* )ad( cant ma$e HO sta*s at od canne 6re7uenc* pannin,( co'era,e/dominance area pannin,

No ,ood ce to ma$e HO o'era,e pannin,( ac$ o0 sites or azimut/tit/antenna optimization

Hard#are 0aiure HO timer e4pires -T"/T1 s*ncronization pro)em

Discrepancies in -T"/-" parameters ec$ a -T" parameters @I( -"I( CA( -"( 6re7.( Adacencies(

HO parameters #it ND reports/NM" comparin, to rea dri'e data.



34/34



A0ter dri'e test data and NM" report ana*sis pan neededparameter can,es.

E4ecute can,e re7uests impementin, ne# parameter 'auesusin, NM".

Ma$e ne# dri'e test at same area a0ter parameter can,es or i0not possi)e stud* NM" data #it ND reports @needs rea traWc.

"tart ana*sis and stud* i0 more can,es are re7uired.

Hando'er 0aiure does not necessari* mean drop ca it can stista* at od canne and ma$e ne# HO attempt ater eiter tosame adacent ce or some oter adacent ce.

HO Process&Optimization

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HO Process&Optimization