Network Configuration Optimization

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1 © 2007 Nokia 13-468259 v1.0

Company Confidential

Network Configuration

Optimization

RANOP / 2007



2 © 2007 Nokia 13-468259 v1.0


Summary

• CM Theory

• BSC Tables

• Default, Specific and Sensitive Parameters

• CM Process• Design default sets

• Consistency Checks

• Review Neighbour Plan

• Review Frequency Plan

• CM Examples

• Examples of wrong parameter set with impact on network

operation/performance

• CM Tools

• Nokia NetActTM Planner, Nokia NetActTM Optimizer and RAC Tools



3 © 2007 Nokia 13-468259 v1.0


CM Theory

BSC Tables

Default, Specific and Sensitive Parameters


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BSC Tables

ADCE POCHOCTRX

BTS

BCF

BSC

RTSL

MA, BA

SEG




Define Default sets

Default Parameters: Almost all parameters areset to default values

Specific Parameters: Are set during planning phase, e.g.frequency, BSIC etc.

Default, Specific, and Sensitive Parameters

Sensitive Parameters:Changes in some default parameters

are quite dangerous as they may

have a critical impact on the network.

Care must be taken.




1. Default parameters

• BSC, BTS, HOC, POC, ADCE, TRX tables

Sensitive parameters

• BTS table: HOP, BAR, PLMN, ACC, RXP, TLC, PMAX, DMAX, TRP, IDLE, ACT, RDIV

• POC table: PMAX, UDR, UUR, LDR, LUD

• HOC table: EPB, HPP, LDWS, LUWS, QDWS, QUWS, QDR, QDP, QDN, QUR, QUP, QUN, LDR, LDP,

LDN, LUR, LUP, LUN,• ADCE table: PMRG, LMRG, QMRG, MRGS

2. Specific parameters

• BTS table: BSC id, BCF id, SEG id, BTS id, BTS NAME, Cell id, MCC, MNC, LAC, RAC, NCC, BCC, MAL,HSN1, HSN2, MO, MS, CDEF, CDED

• ADCE table: BSC id, BTS id, N-LAC, N-Cell id, N-BCCH, N-NCC, N-BCC, synchronised

• TRX table: BSC id, BTS id, TRX id, FREQ, TSC, TSL configuration

Microsoft Excel

Worksheet

Default, Specific and Sensitive Parameters



7 © 2007 Nokia 13-468259 v1.0


CM Process

Design default sets

Consistency Checks

Review Neighbour Plan

Review Frequency Plan



8 © 2007 Nokia 13-468259 v1.0


CM Process - Summary

• Design default sets

• Consistency Checks

1. Compare network design against network configuration

• Default Parameter Check• Specific Parameter Check

2. Database check

• Check inconsistencies between TRX, BTS table with ADCE table:

• Check Adjacencies to non-existing cells

3. Consistency parameter checking

• Neighbour cells with co-BSIC, co-BCCH ...

• Review Neighbour Plan

• Review Frequency Plan



9 © 2007 Nokia 13-468259 v1.0


Design default sets

• Define default parameter sets - sector template

• Macro 850/900

• Macro 1900/1800

• Micro 850/900

• Micro 1900/1800

• Dense-Urban

• Rural

• Define default neighbour sets – adjacency template• Macro 850 – Macro 850

• Macro 850 – Macro 1900

• Macro 850 – Micro 850 ...

• Sector creation through dat or xml file according to:

• Sector template

• Sector specific parameters

D e f a u l t s e t s c o n s i s t o f

M M L d e f a u l t v a l u e s + r e c o m m e n d e d v a l u e s



10 © 2007 Nokia 13-468259 v1.0


Consistency Checks

OSS

CM DatabaseCM Database

E x p o r t

Parameter file

Master configurationdatabase

actual default

planned

default

actual specific

NetAct Planner

Planning

database

Parameter file

export

import

I m p o r t

Consistency

check

Parameter file

I m p o r t E x p o

r t

Mapinfo

ODBC

Consistencycheck

Consistency

check



11 © 2007 Nokia 13-468259 v1.0


CM Process

Compare network design against network configuration

Default Parameter Check

Specific Parameter Check

11 © 2007 Nokia 2. Network Configuration Optimization / 2007-05-31 / Initials




12 © 2007 Nokia 13-468259 v1.0


Compare network design against network

configuration

Configuration

analysis

Real system

configuration

Planned systemconfiguration

"What's in the system is not always what we planned to be there"



13 © 2007 Nokia 13-468259 v1.0


OSS

Operational department

Planning department

Default parameter check

• Databases :

• Responsibilities :

BSC

BSC

BSC

actual default

planned

default

actual specific

Master configuration

database

Consistency

check

N o t e : V e r i f y d e f a u l t s e t t i n g s a r e

O K b e f o r e d o i n g c o n s i s t e n c y

c h e c k i n g i n c a s e p a r a m e t e r

p l a n n i n g w a s d o n e b y o t h e r s ! ! !



14 © 2007 Nokia 13-468259 v1.0


Default parameter check

• Default parameter checking

• Export Actual Default Parameters from the OSS through a xml file, for e.g.

• Import xml file into a Database using for e.g. CM Plan Editor.

• Compare Planned Default Sets with Actual Default Parameters in the network.• Mark exceptions for each default parameter

• Show differences

• Select changes to be done

• Create dat file or xml file for correction

It is very important to verify if any changes to Default Parameters has

been done before any optimization, as this may result in undesired and

unexpected impacts on the network.



15 © 2007 Nokia 13-468259 v1.0


OSS

Planning toole.g. NetAct

Operational department

Planning department

Specific parameter check

• Databases :

• Responsibilities :

BSC

BSC

BSC

actual default

planned

default

actual specific

Consistency

check

Master configuration

database



16 © 2007 Nokia 13-468259 v1.0


Specific parameter check

• Specific sector parameter checking

• Export Actual Specific Parameters from the OSS through a xml file, for e.g. (this

can be done jointly with Default Parameters)

• Import xml file into a Database using for e.g. CM Plan Editor • Import Planned Specific Parameters from NetAct Planner

• Use GSM Cell Id as key

• Compare Planned Specific parameters with Actual Specific parameters from

OSS (mainly LAC, RAC, frequencies, hopping parameters and neighbours)

• Mark exceptions for each default parameter


• Select changes to be done• Create dat file or xml file for correction

It is very important to verify if Specific Parameters have been correctly

implemented before any optimization



17 © 2007 Nokia 13-468259 v1.0


CM Process

Database check





18 © 2007 Nokia 13-468259 v1.0


Database check

OSS

BSC

BSC

BSC

•BTS•HOC•POC

•BTS•HOC•POC

•BTS•HOC•POC

ADCE ADCE

ADCE

Consistency

check



19 © 2007 Nokia 13-468259 v1.0


BSC A BSC B

OSS 1

BSC C

OSS 2

Database check



20 © 2007 Nokia 13-468259 v1.0


• Database check of Actual Parameters

• Export all Parameters from the OSS through a xml file, for e.g.

• Import xml file into a Database using for e.g. CM Plan Editor.

• Check inconsistencies between TRX, BTS table with ADCE table:• N-BCCH in ADCE table against FREQ in TRX table

• N-LAC, N-NCC, N-BCC in ADCE table against LAC, NCC, BCC in BTS table

• Check Adjacencies to non-existing cells


• Select changes to be done

• Create dat file or xml file for correction

Inconsistencies in tables can generate drop calls during HOs, for e.g.

f AB

Database check

Database check



21 © 2007 Nokia 13-468259 v1.0


BSC id BTS id TRX id FREQ

f A

BSC id BTS id N-LAC N-Cell id N-BCCH

f AB

TRX

ADCE

N-Neighbour

Cell A Cell B

f AB

f A

applies also to other cell parameters !!

Database checkN-BCCH in ADCE table against FREQ in TRX table



Database check



23 © 2007 Nokia 13-468259 v1.0


Cell A

Cell C

OMC 1 OMC 2

Cell B

• Cell B is deleted but incoming adjacencieswere not removed

• Cell C is not known in OMC Area 1 database

BSC 2

BSC 1

Database checkAdjacencies to non-existing cells

Database check



24 © 2007 Nokia 13-468259 v1.0


=============================================================================== ADJ ACENCI ES TO NON- EXI STI NG OR FOREI GN CELLS= Net wor k: PLMN= Ar ea: Al l BTCHs sel ect ed= Sor t i ng key: sour ce BSC name, sour ce BTCH I D===============================================================================Nor mal l y ever y adj acency shoul d be t owar ds an exi st i ng cel l .I n t hi s r epor t al l adj acenci es ar e checked so t hat t he adj acent cel l

( c_bTCH: ci , l ac) r eal l y i s f ound i n t he Noki a Net Act dat abase i n t he c_bTCH t abl e.Di scr epanci es ar e r epor t ed.

I nst r ucti ons:Remove t he i ncor r ect adj acenci es by t he Top- l evel User I nt er f ace af t er compar i ng the repor t t o the pl an.Not e t hat i f t he adj acent cel l exi sTCH i n anot her Noki a Net Act , no cor r ect i on i s needed.Not e: Runni ng t hi s r eport t akes a f ew mi nut es. Pat i ence pl ease.===============================================================================

Adj acenci es t o non- exi st i ng cel l sSour ce Sour ce Sour ce ADJ . CELL ADJ . CELLBSC ( BTCH i d) BCF/ BTCH BTCH i nt _i d LAC CI- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -BSC533( 48) BSC533 118112 22871 1022

Ci d 2413BSC552( 24) 102679 22870 3291BSC553( 1) 97461 22870 3301

BSC553( 2) 97769 22870 3301BSC553( 4) 98375 22870 3301BSC553( 10) 99316 22870 3142

Adjacencies to Non-existing or

Foreign Cells (065) - Example

Database checkAdjacencies to non-existing cells



25 © 2007 Nokia 13-468259 v1.0


CM Process

Consistency parameter checking





26 © 2007 Nokia 13-468259 v1.0


• Check cells in MSC vs cells in BSC

• Check external adjacencies in MSC

• Cells with co-channel frequencies

• Cells with adj-channel frequencies• Non symmetrical adjacencies

• Neighbours with co-channel frequencies

• Neighbours with adj-channel frequencies

• Neighbours of a same cell with co-BSIC, co-BCCH

• Check BCCH-BSIC reuse distance

• Check BCCH reuse distance

• Check site with same MA List in different sectors and different HSN

• Check site with same MA List in different sectors and MAIO collision

• Synchronized HO

Consistency parameter checking



27 © 2007 Nokia 13-468259 v1.0


Cell A Cell B

Cells with co-channel and adj-channel frequencies

FREQ=10 FREQ=9,10,11

• Co-channel frequencies: HO is not possible in case of co-BCCH

• Adj-channel frequencies: Ho is possible but might fail due to interference.

A

B

-6dB -9dB

N t i l dj i



28 © 2007 Nokia 13-468259 v1.0


Cell A Cell B

Non symmetrical adjacencies

• Find all non symmetrical adjacencies :

• cell B is neighbour of Cell A

• cell A is not neighbour of Cell B

Neighbours with co-channel and adj-channel



29 © 2007 Nokia 13-468259 v1.0


Neighbours with co channel and adj channel

frequencies or co-BSIC, co-BCCH

Cell A

f=24

Cell B

f=10, BSIC=2,2

f=24f=9,10,11

f=10

• Neighbours with co-BSIC, co-BCCH:

Might generate ghost-access andHO drop calls.

High sdcch abis failure and highhandover failure could be indicators

for this case.

• Neighbours with co-channel or

adjacent channel frequencies:

Will cause interference betweenneighbour cells

Cell C

f=10, BSIC=2,2

Ch k BCCH BSIC d BCCH di t



30 © 2007 Nokia 13-468259 v1.0


Check BCCH-BSIC and BCCH reuse distance

• Small distances may be dangerous!

Reuse 4/12

FREQ = 234

BSIC = 42

FREQ = 234

BSIC = 42

FREQ = 234

S h i d h d



31 © 2007 Nokia 13-468259 v1.0


Synchronised handover

Site BSite A

• Non-synchronised Handover

• MS sends access bursts (HO_ACCESS) (with varying TA) until it receives

PHYSICAL_INFO

• Synchronised Handover

• MS sends a few access bursts (HO_ACCESS) and then starts transmission with

previous TA

• Non-synchronised handover leads to a longer communication interruption than

synchronised handover (200ms vs. 100ms)

• Synchronized HO should be activated between sectors of the same site. If activated

on inter-site adjacencies the handover can fail

Synchronized HONon- Synchronized HO

CM Process



32 © 2007 Nokia 13-468259 v1.0


CM Process

Review Neighbour Plan



Review Neighbour plan



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Review Neighbour plan

• Neighbour planning• According to best server areas

• Neighbour optimisation adding

• Activate double BA List feature in cells to be integrated/optimised

• Analyse Undefined Adjacent Cell Measurements

• Activate channel finder measurements

• Add neighbour cells appearing with high RxLev and many occurences

• Neighbour optimisation deleting

• Activate handover adjacent cell measurements

• Find pair of cells with low number of attempts incoming and outgoing

• Delete corresponding adjacencies• Remark: number of adjacencies should be optimised (minimised) in order to

facilitate the measurement tasks performed by the handsets

Note: Even when Optimizer is used for automatic Neighbour Optimization, Double BA List and Channel Finder features needto be activated in order to collect measurements from the Network.



Double BA List



35 © 2007 Nokia 13-468259 v1.0


Double BA List

Parameter Value

bCCHAllocation-ID 1 ... 255

bCCHAllocationList 1 ... 124 in GSM (max. 32 freq. for all bands)

idleStateBCCHAllocation 0 (BCCH list is taken from the adjacent cell)

1 ... 255 (number of the BCCH list used)

measurementBCCHAllocation ADJ (BCCH frequency list taken from adj. cell)IDLE (active MS uses same list as MS in IDLE mode)

initialFrequency 1..124 & 975..1023, 0; 512..885 GSM900;1800 (FREQ TRX)

Undefined Adjacent Cell Measurement



36 © 2007 Nokia 13-468259 v1.0



• Registers statistics on cells, which have not been defined as adjacent cells butwhich are among those six neighbouring cells, that the MS receives best

Source BTS

Defined Adjacencies in source BTS

Among the best measured Adjacencies by the Mobile but not

defined as adjacencies in the SourceBTS. These Adjacencies to bereported in the Undefined AdjacentCell Measurement

Both defined as Adjacencies in thesource BTSand among the 6 bestmeasured Adjacencies in the Mobile.These are the only one to make thehandover to if necessary.




37 © 2007 Nokia 13-468259 v1.0



Average strength of the downlink signalreceived from an undefined adjacentcell

Number of samples for calculating the average DLsignal strength

BCCH, NCC, BCC of adjacent cell

Network Doctor 073



Channel finder measurement



39 © 2007 Nokia 13-468259 v1.0


Measreport

Undefined Adjacent Cell dBm - Serving Cell dBm

(update current counter)

Counter 1

(dBm value below 0)

Counter 2

( 0 < dBm value < 6)

Counter 3

(dBm value >6)

500 5000 2000

Values after 1hour measurementperiod

Dominating Good candidate for a defined cell

3600 sec / 0.48 sec = 7500 samplings during one hour

Channel finder measurement

Decision mechanism

Adjacent cell measurements



40 © 2007 Nokia 13-468259 v1.0


Adjacent cell measurements

Nbr of HO Attemptsoutgoing and incoming

In case Number of HO Attemptsis very low to a certain cell,consider removing this cell from

Adjacency list.

Network Doctor 153

CM Process



41 © 2007 Nokia 13-468259 v1.0


CM Process

Review Frequency plan






42 © 2007 Nokia 13-468259 v1.0



• Optimise BCCH-BSIC reuse in cities ( no repetitions)

• Optimise BCCH reuse

• Implement new frequency plan with Optimizer using existing band splitting

strategy• Implement new frequency plan with Optimizer using existing band strategy

• Simulate new band strategies in simulation tool (1/1, 1/3, 3/3, heuristic RF

hopping with different number of frequencies)

• Implement the strategy that gives the best simulation result




43 © 2007 Nokia 13-468259 v1.0


BCCH-850

0

10

20

30

40

50

60

70

80

90

1 28 1 29 1 30 1 31 1 32 1 33 1 34 1 35 1 36 1 37 1 38 1 39 1 40 1 41 1 42 1 43 1 44 1 45 1 46 1 47 1 48 1 50 1 51 1 52 1 53 1 56 1 57

BCCH 850

#

q y p

BCCH-BSIC 850

0

2

4

6

8

10

12

14

16

18

20

1 2 8 - 0 0

1 2 8 - 4 7

1 2 9 - 1 6

1 2 9 - 6 3

1 3 0 - 3 2

1 3 1 - 0 1

1 3 1 - 4 8

1 3 2 - 1 7

1 3 2 - 6 4

1 3 3 - 3 3

1 3 4 - 0 2

1 3 4 - 4 9

1 3 5 - 1 8

1 3 5 - 6 5

1 3 6 - 3 4

1 3 7 - 0 3

1 3 7 - 5 0

1 3 8 - 1 9

1 3 8 - 6 6

1 3 9 - 3 5

1 4 0 - 0 4

1 4 0 - 5 1

1 4 1 - 2 0

1 4 1 - 6 7

1 4 2 - 3 6

1 4 3 - 0 5

1 4 3 - 5 2

1 4 4 - 2 1

1 4 4 - 6 8

1 4 5 - 3 7

1 4 6 - 0 6

1 4 6 - 5 3

1 4 7 - 2 2

1 4 7 - 6 9

1 4 8 - 3 8

1 5 0 - 0 7

1 5 0 - 5 4

1 5 1 - 2 3

1 5 1 - 7 0

1 5 2 - 3 9

1 5 3 - 0 8

1 5 3 - 5 5

1 5 6 - 2 4

1 5 6 - 7 1

1 5 7 - 4 0

BCCH-BSIC

#

Optimize BCCH-BSIC reuse in

cities (no repetitions)

Optimize BCCH reuse



44 © 2007 Nokia 13-468259 v1.0


CM Examples

Examples of wrong parameter set with impact on network

operation/performance

Examples of wrong parameter set with impact onnetwork operation/performance – call setup qual



45 © 2007 Nokia 13-468259 v1.0


network operation/performance call setup, qual,

bands1. No calls happening in a cell

• Cell Barred

• Non existent (LAC, Cell ID) in MSC

• DMAX = 0

2. Very few calls happening in a cell

• RxLevAccesMin

• Wrong MNC, MCC, LAC declaration

3. Very low traffic in a cell

• msTxPwrMax = 0, bsTxPwrMax = 30

4. Bad quality in UL after rehoming

5. Few traffic in 1800 layer of a dual band 900/1800 network

Example 1a



46 © 2007 Nokia 13-468259 v1.0


p

9

8

Handover

Call Setup

S Y S I N F O

3 ( B C C H )

( C e l l B a

r r A c c e s s = y e s )

• No calls happening in a cell:The cell has been barred

Example 1b



47 © 2007 Nokia 13-468259 v1.0

Company ConfidentialMSC does not find

(LAC, CI) in its

database

• No calls happening in a cell:

CI different between MSC and BSC or non existent (LAC, Cell ID) in MSC

Example 1c



48 © 2007 Nokia 13-468259 v1.0


• No calls happening in a cell:MsMaxDistanceInCallSetup (DMAX) = 0

DMAX = 0

RxLevel =-70 dBm

8

Call Setup

Despite the coverageof the cell, no calls will

be established!

Example 2a



49 © 2007 Nokia 13-468259 v1.0


• Very few calls happening in a cell:

RxLevAccesMin

Cell coverage

RxLevAccessMin = -47 dBm

Mapping OSS database BSS MML

Lowest range 0 -110 dBm

1 -109 dBm

... ...

62 -48 dBm

Highest range 63 -47 dBm

Be careful when setting

parameter through xml or datfile! OSS database unit should

be used to specify parameter

value!

Example 2b



50 © 2007 Nokia 13-468259 v1.0


• Very few calls happening in a cell:Wrong MNC, MCC, LAC declaration in network - MNC: 01 ≠ 1 !!! (In OSS correct

value)

Example 3



51 © 2007 Nokia 13-468259 v1.0


bsTxPwrMax 0 … 30 dB 0 dB

bsTxPwrMin 0 … 30 dB 30 dB

minMsTxPower 0 … 36 dBm 0 dB

msTxPwrMax 0 … 36 dBm

Parameter Value_______Default

value

BTS Max Power = BTS Power – (bsTxPwrMax = 0 dB)

BTS Min Power = BTS Power – (bsTxPwrMin = 30 dB)

Attenuation Values (dB)

Power Values (dBm)

MS Max Power = (msTxPwrMax = 33 dB)

MS Min Power = (minMsTxPower = 13 dB)

A b s o l u t

e

∆ D e l t a

• Very low traffic in a cell:msTxPwrMax = 0, bsTxPwrMax = 30

Example 4



52 © 2007 Nokia 13-468259 v1.0


• Bad quality in UL after rehoming:DiversityUsed parameter not set to yes anymore

RDIV = Y

Uplink Diversityimproves quality of

signal received.

After rehoming

RDIV

parameter wasset to default

value (No) and

UL quality was

affected.

Example 5



53 © 2007 Nokia 13-468259 v1.0


• Few traffic in 1800 layer of a dual band 900/1800 network:Idle Mode: C2 parameters not set properly (temporaryOffset, penaltyTime)

BCCHBCCH

fast moving mobileslow moving mobile

1800: micro-Layer 900: macro-layer

Examples of wrong parameter set with impact on

network operation/performance upgrade



54 © 2007 Nokia 13-468259 v1.0


network operation/performance – upgrade

1. High drop call rate after upgrading a cell from 4 to 6 TRXs

• Update MAL, no update of MAIO offset

• TRXs with different power without ICE activated

Example 1a



55 © 2007 Nokia 13-468259 v1.0


• High drop call rate after upgrading a cell from 4 to 6 TRXs:Update of the MAL with no update of the MAIO offset

Example 1b



56 © 2007 Nokia 13-468259 v1.0


• High drop call rate after upgrading a cell from 4 to 6 TRXs:TRXs with different power without ICE activated

Coverage

BCCH - TRX

Capacity

MS in a region covered only by Coverage-TRX, ICE not activated.

Result: BTS may allocate a TSL in Capacity TRX. Call will drop.

Traffic - TRX

Example 1b



57 © 2007 Nokia 13-468259 v1.0


• TRXs with different power

Dual Duplex UnitTRX RF Units

Antennas

TX

RXmaindiv

WBC

Receive Multicouplers& Wideband Combiners

TX/RX ant TX/RX-div

ant

XX

X

XX

X

TX

RXmaindiv

TX

RXmaindiv

TX

RXmaindiv

TX

RXmaindiv

TX

RX maindiv

WBC

D u pl ex er LNA

D u pl ex e

r LNA

D u

pl ex er LNA

D u pl ex er LNA

+3dB


network operation/performance – frequencies



58 © 2007 Nokia 13-468259 v1.0


network operation/performance frequencies

1. Drop call rate increase after new frequency plan implementation

• Double BA List activated

2. Impossibility to unlock some BTS after a RF-frequency hopping

implementation

3. Impossibility to unlock some BTS after a frequency retune

• NON-EDGE TRX, with GTRX = Y

• TRX, with GTRX = Y, not attached to any EDAP pool

4. No handover happening after frequency retune between 2 cells from

different BSCs

• ADCE table has not been updated for other BSC

Example 1



59 © 2007 Nokia 13-468259 v1.0


• Drop call rate increase after new frequency plan implementation:In the meantime, measurementBcchAllocation has been changed to idle and MA list

defined with old BCCH frequency band

BCCH TCH OLD FREQUENCY PLAN

BCCH TCH NEW FREQUENCY PLANTCH

OLD MA List

These BCCH frequencies will not be measured by old MA List

These TCH frequencies will be wrongly measured

Example 2



60 © 2007 Nokia 13-468259 v1.0


• Impossibility to unlock some BTS after a RF-frequency hopping implementation: After frequency hopping retune, some BCCH frequency equal to TRX frequency

of non-BCCH TRXs

After changing TRX frequency, verify BSIC and TSC (Training Sequence Code)

is changed accordingly.

Example 3a



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• Impossibility to unlock some BTS after a frequency retune:NON-EDGE TRX, with GTRX = Y, in a cell with EGENA set to yes

B

BTS

NON-EDGETRX(s)

(E)GPRS territory

EGENA = Y

SEG

GTRX = Y

EDGE TRX(s)

BTS

NON-EDGETRX(s)

EGENA = Y

SEG

GTRX = N

EDGE TRX(s)

B

(E)GPRS territory

GTRX = Y GTRX = Y

Example 3b



62 © 2007 Nokia 13-468259 v1.0


• Impossibility to unlock some BTS after a frequency retune:TRX, with GTRX = Y, not attached to any EDAP pool in a cell with EGENA set

to yes

BTS

NON-EDGE

TRX(s)

EGENA = Y

SEG

GTRX = N

EDGE TRX(s)B(E)GPRS territory

GTRX = Y

EDAP pool

1

2

Add TRX-1 to EDAP pool

Example 4



63 © 2007 Nokia 13-468259 v1.0


• No handover happening after frequency retune between 2 cells from differentBSCs:

Frequency retune has been done with MML command. ADCE table has not been

updated for incoming adjacencies belonging to other BSCs

BSC id BTS id TRX id FREQ

f A

BSC id BTS id N-LAC N-Cell id N-BCCH

f AB

TRX

ADCE

N-Neighbour

Cell A Cell B

f AB

f A


network operation/performance – Handover



64 © 2007 Nokia 13-468259 v1.0


p p

1. No handover from a cell towards all its neighbours• PLMN permitted = No

2. High Handover failures after implementation of new adjacency plan

• SYNC = YES

3. No handover happening from an interfered cell

• hoMarginQual set to 0

4. 100% of handover failures in an adjacency relation

• Co-BSIC co-BCCH declaration

5. High number of handovers

• hoThresholdsLevUL = hoThresholdsLevDL

6. Handover not happening when DL signal level of neighbour much greater thanserving cell

• POC DL activated

Example 1



65 © 2007 Nokia 13-468259 v1.0


• No handover from a cell towards all its neighbours:PLMN permitted not set properly. MML Default value is the NCC of the BTS. So HOs will

not happen towards neighbours with different NCC.

Cell ANCC 3

Cell BNCC 4

Plmn permitted 0 = No

….

Plmn permitted 3 = Yes

Plmn permitted 4 = No…

Plmn permitted 7 = No

Set Plmn permitted 4 = Yes

PLMN permitted parameter consists actually of 8 parameters (0 …7) related to the NCCpart of the BSICs of neighbour cells. MS only reports measurements of cells with NCCpermitted (plmn permitted = YES).

No Measurement reports of CellB are sent to BSC. So no HOs

occur from Cell A to Cell B

Example 2



66 © 2007 Nokia 13-468259 v1.0


• High Handover failures after implementation of new adjacency plan All adjacencies have been implemented with synchronised parameter set

to yes. HOs between cells of different sites will probably fail.

SYNC = YE

SYNC = NONew Channel, New Cell

ACTIVE CALL

HANDO CMD

HANDO ACC

HANDO COM

ACTIVE CALL

MS NETWORK

Old Channel, Old Cell

PHYS INFOx

Synchronized Handover Set SYNC = YES

only between

sectors of the

same site.

Recommendation is to have Sync HO within BTSs in the

same BCF and Non Sync HO between BTSs in differentBCFs.

Example 3



67 © 2007 Nokia 13-468259 v1.0


• No handover happening from an interfered cellhoMarginQual set to 0

• In an interfered cell, despite high signal strength, quality is not good. So HO Margin Qual

should permit HO to a cell that despite it’s lower signal strength, may have a better quality.

A

B

PBGT margin = 6dBHo Margin Qual = -4

Ho Margin Qual = 0

(MML Default)

Example 4



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• 100% of handover failures in an adjacency relationCo-BSIC co-BCCH declaration

Cell A Cell B

FREQ=10BSIC = 33

FREQ=10BSIC = 33

8

Example 5

Hi h b f h d h Th h ld L UL h Th h ld L DL



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0

1

2

3

4

5

6

7

- 1 1 0

- 1 0 8

- 1 0 6

- 1 0 4

- 1 0 2

- 1 0 0

- 9 8

- 9 6

- 9 4

- 9 2

- 9 0

- 8 8

- 8 6

- 8 4

- 8 2

- 8 0

- 7 8

- 7 6

- 7 4

- 7 2

- 7 0

- 6 8

- 6 6

- 6 4

- 6 2

- 6 0

- 5 8

- 5 6

- 5 4

- 5 2

- 5 0

dBmdBm

QualityQuality

HoThresholdLevUL/DL

HoThresholdInterferenceUL/DL

Interference HoInterference Ho

No Action NeededNo Action Needed

Quality HoQuality Ho

Level HoLevel Ho

HoThresholdLevDLHoThresholdLevUL

• High number of handovers. hoThresholdsLevUL = hoThresholdsLevDL

hoThresholdsLevUL,

high thresholds will

anticipate HOs:

-95 -> -100

hoThresholdsLevDL:

-95 -> -90

Example 6



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• Handover not happening when DL signal level of neighbour much greater thanserving cell

Power control DL activated

A

B

-6dB

-3dB

Power Control

-9dB


network operation/performance – Background Plan



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OSS

BSC

BSC

BSC

Plan

8

8

Background Loading of

Radio Network Plan


network operation/performance – Background Plan



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1. Few handovers after implementation of new adjacency plan

• Only half of the plan has been downloaded. Half of the adjacencies missing.

2. High drop call rate in some sites after frequency hopping activation• Some sites did not hop as some frequencies were not correctly set!

Important to verify network parameters through MML command!

In case not all parameters were changed correctly, use MML to

implement the changes!

Examples of wrong parameter set with impact onnetwork operation/performance – PRFILE, MSC,

SGSN



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BTS BSC

MSC

SGSN GGSN Internet

PSTN

GPRSBackboneIP Network

GPRS Core

PARAMETERS

PRFILE+

PARAMETERS

PARAMETERS

SGS

Examples of wrong parameter set with impact onnetwork operation/performance – PRFILE, MSC,

SGSN



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1. No queuing happening after activating it with BTS parameters.

• Queuing should be activated also in BSC PRFILE (PREEMPT_USAGE parameter set

to FF) and in MSC!

2. No rejection due to distance when activating the parameter

msMaxDistanceInCallSetup.

• The parameter DISTANCE_VERIFYING should be set to FF in BSC PRFILE

3. Tremendous amount of GPRS attaches.

• The detach timer set to 01h00 in the SGSN! Verify parameters in SGSN related to

implicit detach.

4. Mal functioning MS and Bad RxQual DL.

• DL DTX is activated in BSC level and by MSC parameters in cell level. It is not

recommended to activate DL DTX, specially when BB Hopping is being used.


network operation/performance – PRFILE, MSC, SGSN



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5. Paging request decrease after msPeriodicLocationUpdate settingDEREGISTRATION TIMER < msPeriodicLocationUpdate!

Verify the parameters in BSC and MSC are correctly set.

E.g. of values

BSC: msPeriodicLocationUpdate (BTS) 4-6hrsMSC: Implicit IMSI Detach Time Limit (VLR) 12 hrs

Loitering time (VLR) 24hrs


network operation/performance – BSC



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6. Tremendous amount of Location updatemsPeriodicLocationUpdate = 30 minutes

Too many

Location Updates

will causeSDCCH

congestion!

Conclusion



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• Do consistency checks: verify network parameters are as planned.

• Check configuration!

• Verify differences between OSS template and BSC default parameters!• In some cases recommended values should be used instead of default values (e.g.

msPeriodicLocationUpdate: 0.5 -> 6)

• Verify value of sensitive parameters (e.g. DMAX, RxLevAccessMin)

• Adjust parameters to balance traffic (e.g. C2 in idle mode)

• Inter-related parameters (e.g. New Frequency Plan + BA List)

• Activate parameters in PRFILE, MSC and SGSN (e.g. queuing)

• When downloading background database, verify parameters through MML command(e.g. new frequency plan)

Before suspecting anything, check the parameters active in the network!!!



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CM Tools (Optional)

Nokia NetActTM

Planner Nokia NetActTM Optimizer

RAC Tools

PLANNING & ROLLOUT OPTIMIZATIONOPERATIONS NetActSQM

Nokia NetAct™



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NetActMultiRadio

Planner

NetActOptimal Planner

NetActTransmission

Planner

NetActOptimal Planner

NetActOptimizer

NetActService Optimizer

NetActRAC

FieldMeasurements C

MD

B

NetActMonitor (FM)

NetActInspector

NetActReporter

NetActTraffica

F M

C D R

P a s s i v e P M

A c t i v e P M

P

MDB

Nokia NetActTM Planner



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• MultiRadio Planner

• Support GSM, GPRS, WCDMA Technology

• 2G-2.5G Radio network planning

• General Planning Support : coverage, capacity and frequency planning

• Microcellular network planning

• Dual-band planning• Frequency Hopping planning

• Data service planning

• AMR and HR support

• 3G Radio network planning

• Monte Carlo simulations

Nokia NetActTM Optimizer



81 © 2007 Nokia 13-468259 v1.0


• Perform Frequency allocation

• BCCH and TCH allocation

• RF Hopping allocation: MA-lists MAIOparameters, HSN

• Other necessary parameters: TSC,

BSIC, all IDs

• Perform adjacency optimisation

• Automated adjacency creation based on measurements

• Automated adjacency deletion based on KPIs

RAC Tools - CM Plan Manager



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CM

Analyser

Radio Access Configurator Application Layer

CM

Provisioner

CM

Editor

CM Plan

Manager

Provided functionality:

• Plan import / export (XML file format)• Actual network data export

• Plan identification and browsing

• User-defined plan status visualization and control

• Plan deletion

RAC Tools - CM Editor



83 © 2007 Nokia 13-468259 v1.0


CM

Analyser


CM

Provisioner

CM

Editor

CM Plan

Manager


• Plan creation

• Plan content browsing

• Actual data visualization

• User configurable parameter views

• Parameter mass modification

• Template management

• Integrated GSM and 3G object/parameter editing

RAC Tools - CM Analyser



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CM

Analyser


CM

Provisioner

CM

Editor

CM Plan

Manager


• Predefined rules for consistency checks

• Rule result status information

• Defined action property in rules - automated correction, automated

inconsistency reporting

• Integration with other Radio Access Configurator functionality• Support of simultaneous consistency check operations

RAC Tools - CM Provisioner



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CM

Analyser


CM

Provisioner

CM

Editor

CM Plan

Manager


•User Requested / Scheduled Plan download to network

•Maintaining the timestamp and originator of the last download

•Download progress tracking and status feedback

•Support of simultaneous download operations• Access control and authorization

Network Configuration Optimization

Documents

Transcript of Network Configuration Optimization