142162167 7 8network doctor reports day7 day8

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Babak Kardel

Mehrdad Sedaghat

April 2008

Network Doctor Reports Course



Topics

4/8/20082

• Introduction : Network Doctor Operation

• Report-196: UL and DL Quality, UL Interference Per TRX

• Report-208: Link Balance Per TRX

• Report-153: Handover Failure Ratio on Adjacency• Report-163: TCH Drop Call Ratio

• Report-166: SDCCH Drop Ratio

• Report-204: NETWORK BENCHMARK STATISTICS

• Report-073: Undefined Adjacent Cells

• Reports Number 154, 156, 139, 187 and so on



Introduction:Network Doctor

Operation



Introduction- ND Operation (1) Network Doctor for BSS

Network Doctor for BSS offers a menu-based user interface

in which you can move up and down the menu hierarchy.

All reports are listed in the submenus.

Self-documented reports, front-page descriptions, and

column headers guarantee that the basic information isalways available in a context-sensitive presentation. The

descriptions of the counter formulas can be displayed on

request.

The Network Doctor reports produce an output file whichopens in the dtpad editor window. You can modify the

report, if necessary, and save it.



Introduction- ND Operation (2)When running the BSS Network Doctor reports, a common

query is made for the time period selected and the scope of

the measurement. You can usually define the followingparameters:

Period of time

Today, Absolute date, Relative date ending on the current

hour, Relative date ending the previous midnight.

Scope of report

Maintenance Region, BSC, LAC, one BTS, all BTSs or all

IUO BTSs, single Segment, single BCF, BSC SW version,Frequency band of dual band, BCF type for Base Station

generation, manual Working Set with BTSs or with BCFs,

MSC, and BTS having GPRS traffic.



Introduction- ND Operation (3)Network performance can be evaluated using KPIs such as

TCH drop call ratio. These indicators are either directly

mapped to a counter or a formula of counters. Drop callratio, for example, is currently a formula of several counters.

KPIs need to be:

monitored on network and area level for seeing the trends.

monitored at cell level across the area to spot the BTSs

potentially having problems. Often they are referred to as

BTS Hit Lists or Top n Lists.

analysed for a specific BTS when the BTS has been found onthe Hit List. At this point, for example, you may be interested

in the behaviour of the cell against a time profile.



Network Doctor for BSS : Main Menu*******************************************

* BSS NETWORK DOCTOR *

* v.3.1.9 *

* for NetAct OSS3.1ED3, BSC S11 *

*******************************************1) Fault Management ...

2) Configuration Management ...

3) Performance Management BSS ...

4) Benchmark and analysis ...

5) NetAct Database Administration ...6) Run a report by identification number

7) Display a model report by identification number

8) Generate auto script by identification number

9) User log

10) Connect as another user

s) Search reports containing given formula or counter.

f) Find description of given formula.

c) Change history.

q) Exit



Network Doctor for BSS : Sub Menu Benchmark and analysisBenchmark and analysis

Benchmark Benchmark

1 ) Performance statistics (heavy benchmark, use small area, 200)

2 ) Network benchmark statistics (heavy, use small area, 204)

3 ) Performance profiles for area, 10 days/24 h (heavy, use small area, 207)

4 ) Quality Survey (800)

5 ) BTS GSM KPI/PI table, dynamic object and time aggregation (205)

6 ) TRX level GSM KPI/PI table, dynamic time aggregation (206)

AnalysisAnalysis

7 ) BSC doctor (212)

8 ) BTS analyser (216)9 ) Base station site check (221)

10) Cell doctor (211)

11) BTS doctor (213)

12) Availability per BSC unit (215)

13) SDCCH, TCH and BSC out HO observation statistics (217)

14) Drop call trace (225)

15) BSC internal HO observation cause statistics (223)

m ) Display a model report by ID number

r ) Run any other report by ID number

q ) Quit



Network Doctor for BSS : Sample

-------------------------------------------------------------------------------------------------

Report Generation Data

-------------------------------------------------------------------------------------------------

Date : Wed Sep 26 16:21:56 BST 2007

Menu Command Path : 6 / 132

User / Host : kardel / nscs2

Version / Report : ND BSS v.3.1.9 / 132

========================================================

= CELLS HAVING SMS ESTABLISHMENT FAILURES

= Network: PLMN

= Area: BSC - 711883

= Period: from 20070926 to 20070926

= Aggregation: Segment

= Threshold : nbr of failures >0= Sorting : SMS fail

========================================================




====================================================

This report shows cells having SMS establishment failuresover a given period.

This report can be run on BTS or segment level.

Nbr of SMS est.attempts

/sms_4 Number of SMS establishment attempts.

SMS flr % on TCH /sms_2 SMS establishment failure ratio on TCH.

SMS flr % on SDCCH

/sms_3 SMS establishment failure ratio on SDCCH.

Tot SMS flr %

/sms_1 Total SMS establishment failure ratio.

====================================================




==============================================================

Cells having SMS establishment failures

between 20070926 and 20070926

Nbr of SMS flr SMS flr Tot

SMS est. % % SMS flr

Seg attempts on TCH on SDCCH %

BSC Segment name ID sms_4 sms_2 sms_3 sms_1

--------------- --------------------- -------- ------- -------- --------- ------

B067N N2680B 57 15 11.11 0.00 6.67

B067N NI21021A 85 47 0.00 2.13 2.13

B067N NI21040A 103 155 9.09 0.69 1.29

==============================================================



Web-Based Browser Network Doctor Browser in the Regional Cluster

Network Doctor Browser (ND Browser) is an optional web-based

application that allows you to access the ready-made BSS reports provided

by the HP-UX-based Network Doctor application.



ND Report-196:

UL and DL quality, ULinterference per TRX



Contents

1. SAMPLE OF REPORT

2. DESCRIPTION3. ADVANTAGE

4. ANALYS

5. EXPERIENCES6. INFORMATION



Sample of Report 196 (Part 1)



Sample of Report 196 (Part 3)



This report have three parts:

Part 1: UL, DL Quality and UL Interference per TRX

Part 2: Interference profile

Part 3: Frequency profile

Description of Report 196



Advantage of Report 196

This report can be used to find hardware problems such as

TRX faulty, VSWR, feeder and sector swap. Also this reportcan be used to detect interference and overshooting.



Analyze of Report 196

PART 1: TRX HIT LIST

For each TRX reported:

q0..7 (%) UL /ulq_2 Cumulative % of uplink call samples.

Target value example: q5 over 98 %.

q0..7 (%) DL /dlq_2 Cumulative % of downlink call samples.

Target value example: q5 over 98 %.

Call min /trf_32a Call time in minutes counted from samples.

The max call time for a TRX in a 6 hours period in a day=1 day* 6 hours*60 mins*8 RTSLs*2 (HR)=5760 min

Call dif /trf_21a The ratio of call samples of the most loaded TRXto that of the least loaded TRX in the same BTS.

Sorting the report by using this value may help to

detect abnormal traffic distribution in a cell.

Intrf /itf_4 Average interference band (1-5, 5 being the worst)

Freq Frequency of TRX. 'chgd' = frequency has been

changed during the period. Blank means

that there has been no calls.



Quality classes:The quality classes are as defined in GSM recommendation GSM 05.08 (8.2).

The calls are sampled every 480 ms for the quality class. Quality class info is

used on Abis but BSC converts the quality classes into BER % figures

using the default values. (Power control measurement shows BER figures).

Class BER (GSM 05.08)

***** ******************

qua 0 (BER < 0.2%)

qua 1 (BER 0.2 - 0.4%)

qua 2 (BER 0.4 - 0.8%)

qua 3 (BER 0.8 - 1.6%)

qua 4 (BER 1.6 - 3.2%)

qua 5 (BER 3.2 - 6.4%)

qua 6 (BER 6.4 - 12.8%)

qua 7 (BER >12.8%)

The rule of thumb is that in quality classes 0-5 the MS user does not yet feel

that the quality is bad.




UL Interference:

Band indicates the average interference band of TCH (idle).

If there is no interference (uplink), average band should be 1.

The band limits are defined in cell parameters by setting the boundaries in

the interference averaging parameter set.

------------------ boundary 0 (value fixed: -110dBm)

band 1

------------------ boundary 1 (value eg.: -105dBm)

band 2------------------ boundary 2 (value e.g.: -100dBm)

band 3

------------------ boundary 3 (value e.g.: -95dBm)

band 4

------------------ boundary 4 (value e.g.: -90dBm) band 5

------------------ boundary 5 (value fixed: -47dBm)




PART 2: INTERFERENCE PROFILEFor each TRX exceeding the thresholds and having interference

a 10day/24h breakdown is shown.

- Check the 10-day/24-hour breakdown charts to find out what the pattern is.

- If you suspect that the interference is from the BS itself (constant band 5 interference e.g. in all sectors) you may set

the power to minimum for a while (this means that calls cannot be made!)

and check from the BSC MML with ZERO command if the interference level has

gone down in idle time slots. Then put the power back to the initial level.

- After you have found the cells with obvious external UL interference

you maya) mark the cells having a similar interference pattern on the map with

the same colour and see if the antenna directions point to a certain place

- It is also a good idea to check whether the cell is not reported by report 062,

which could mean interference from an own adjacent cell.

b) use Undefined Adjacent Cell measurement (possibly with the idle state BA

list to define what are the strongest frequencies in the band that are not

adjacent cells.

c) You may also run the report 216 to get more details about the cell.




PART 3: FREQUENCY PROFILE

For all TRXs exceeding the thresholds and having frequency changed during the giventime period a 10day/24h breakdown is shown. The value of zero means that there are no

calls. Frequency changes

must be considered when analysing interference behaviour.




Part 1 more analysis:

If 1 TRX in a cell has low quality :

a- TRX faulty ; There is “ 7607 TRX operation degraded ” or “ 7530 TX output powerlevel decreased “ alarm

b-TX or RX jumper is out of work ; if TRX has no alarms and DL qual is low then TX jumper is out of work and when UL qual is low then RX jumper is out of work.

If 1 TRX has no traffic or low traffic and call diff in cell is high and all RTSLs of thisTRX is idle (ERO command), or TRX is block TRX then TRX is faulty.

When BCCH TRX is faulty, the frequency of TRXs in this cell will change because BTSreplace BCCH to a normal TRX.

In these problems we can replace fault TRX with another TRX and check wiring beforechanging fault TRX. This way sometimes solves problems.




VSWR problem; 2 TRXs of a feeder in a BTS have low qual

Feeder swap; 2 TRXs of a feeder in a BTS and 2 TRXs of a feeder in another BTS in sameBCF have low qual

Sector swap; all TRXs of 2 BTSs in same BCF have low qual without overshoot or

interference Data base swap; it is like feeder or sector swap or cell has no traffic

Overshoot ; all TRXs of a BTS have low qual. We have to check report 232 and site situation.

Interference:

a- interference in all TRXs; cells with same Frequency or same HSN, interference is from theBS itself (Talk family sites or 6+6+6 sites), external UL interference, overshoot

b- interference only in BCCH TRX; check cells with same frequency around this cell andovershooting cells, replace BCCH to another TRX

c- interference only in TCH TRXs; check cells with same frequency around this cell if cell useBB hopping, check HSN in cells with RF hopping, overshoot.




Sample 1 - N255A Call drop



Sample 1 - N255A Tems event

Call drop in

N255A washappened after

an intracell

handover.

N255 has a

6+6+6configuration

and has

interference.



Sample 1 - N255A TCH ass fail



Sample 1 - N255A TA



Sample 1 - N255A report 196

Faulty in TRX 3 of N255A or in RX jumper



Sample 1 - N255A report 208

High DL path loss in TRX 3 of N255A



Sample 1 - N255A Alarm

TRX 3 of N255A is faulty



Sample 2 – N2707C VSWR



Sample 3 – N702B,C feeder swap



Sample 4 – N010 data base swap



Sample 5 – N032B interference and overshoot



ND Report-208:

Link Balance Per TRX



Contents

Sample of Report ND 208

Description of ND 208

Advantage of ND 208

Analyze (Examples) of ND 208

Information



Sample of Report 208



Loss from MS to BTS (UL & DL)

DL Path

Jumper loss between TRX and combiner

Combiner loss

Jumper loss between combiner and feeder

Feeder loss

Jumper loss between feeder and antenna

UL Path

Jumper loss between antenna and feeder

Feeder loss

Jumper between feeder and duplexer

duplexer loss

Jumper between duplexer and TRX (main and diversity)




For having balanced coverage, DL loss should be equal to UL loss Ideally (DL Loss-ULLoss=0). if DL and UL paths be not balanced – for example DL loss be higher than ULloss- then BTS receives good level from MS but MS receives low level from BTS and thequality of call in one direction will be weak, cause dropped call.

DL Path Loss = BS Power – Combiner Loss – DL Signal Strength UL Path Loss = MS Power – UL Signal Strength

Normal Path Loss in DL & UL : 100~115 dbm

Absolute of Normal Balance : < 3~4 dbm

Delta: Deference between lowest and upper link Balance in deferent TRXs

Delta shows if the several TRXs in a cell have the same situation or not. We should detectfaulty path and solve it.

Problems: Rx-Tx BTS Jumper Problem, Combiner Problem, Feeder line Problem, Upperantenna Jumper Problem, loosing connectors and Antenna problem.

Ad t f R t 208




ND Report 208 is a good report for Nokia BTS

troubleshooting. BTS engineers can use this report for

detecting faulty objects and replace them and checkagain if the problem resolved.

R t 208 VSWR P bl



Report 208 – VSWR Problem

Delta > 3 Unbalanced Link

N2007B has VSWR Problem

VSWR S l ti C t L i



VSWR Solution–Connector Loosing

VSWR Problem was solved in N2007B.



Report 208 – Feeder Problem

Feeder Problem in N990B (VSWR in middle of Feeder)

Before Changing Feeder After Changing Feeder

Report 208 Jumper Problem



Report 208 – Jumper Problem

Case1: Jumper from TRX 4 to combiner loose (check connectors at both ends)

Report 208 Jumper Problem



Report 208 – Jumper Problem

Case2: Jumper from Duplexer to TRX 4 (check connectors at both ends)

R t 208 F d P bl



Report 208 – Feeder Problem

Case3: Check common feeder line from

Top of cabinet to Antenna port ( loose

connector’s at either end or High VSWR problem, TRX 2&4 in

this case use the same feeder)

In this case, the Path imbalance (DL-UL) varies

between +1.6 to -4dB which doesn’t tell much

BUT DL pathloss variations between TRX’s is from112.8 to 136dB

& UL pathloss variations between TRX’s is from

111.2 to 140dB

DEFINITELY A PROBLEM!

H t id tif th t ll i t k?



How to identify the worst cells in network?

Import DL & UL pathlosses for all TRX’s ofall cells into separate columns

Use a pivot table to get Min and Max values ofdL and Ul pathlosses in a cell

Identify all cells with DL TRX pathlossvariatons >10dB (for a NW with huge TIquality issues , start with 15dB)

The same can be done for UL also

A combined analyses for DL& UL with >10dBdiff gave a list of 58 cells for UP (West)attached below.

Go back to 208 report for detailed analysis208_HW issues



ND Report-153:Handover Failure Ratio on

Adjacency



REPORT 153 (HANDOVER FAILURE RATIO ON ADJACENCY )

1. SAMPLE OF REPORT

2. DESCRIPTIONS

3. ADVANTAGE

4. ANALYS

5. INFORMATION




Source Target

****** ******

SEGMENT NAME (ID) SEGMENT NAME (ID)

BCF NAME HO=> HO=> HO=> <=HO <=HO <=HO Target BCF NAME

BSC NAME **** **** **** **** **** **** ****** BSC NAME

BAND Att Blck Fail Fail Blck Att LAC BAND

BCF TYPE (%) (%) (%) (%) CI BCF TYPE

------------------ ------ ---- ---- ---- ---- ------ ------ ------------------

N2219C (63) 29 0 7 4 0 23 6210 N603A (7)

N215 12786 N2215

B026N B026N

GSM1800 GSM900

UltraSite UltraSite

N230A (28) 58 0 7 0 0 0 2214 N456C (72)

N217 32268 N456C

B026N B017N

GSM900 GSM900

UltraSite UltraSite




DESCRIPTIONS:

THE ADJACENCIS HAVING HIGH HO FAILURE RATIO , REPORT 153 IS

BASED ON THE OPTIONAL BSC MEASUREMENT HO ADJACENT CELL.

YOU CAN USE THE THRESHOLDS TO FOCUS ON PROBLEMATIC

ADJACENCIES ONLY.

THIS FAMOUS REPORT SPEAKS ABOUT HANDOVER ATTEMPTS

,HANDOVER BLOCKS, HANDOVER FAILS FROM ONE CELL TO THE NEIGHBORS AS TARGET CELLS AND VICE VERSA .




ADVANTAGE:

1. THIS REPORT IS VERY USEFULL TO CHECK HANDOVER

PERFORMANCE FOR A CERTAIN CELL IN BSC

2. WE CAN FIND OUT HANDOVER PROBLEMS (FAILURES) EITHER

INCOMING OR ONCOMING HANDOVER

3.WE CAN FIND OUT WHICH RELATIONS ARE UNNECESSARY AND

WITH CONSIDERING DISTANCE AND DIRECTION OF RELATION WE CAN

DELETE IT SIMPLY.




ANALYS:

1.IF WE HAVE NONE ATTEMPT FROM ONE SIDE WE FIND OUT THERE IS

A PROBLEM FOR THIS RELATION LIKE AS : ONESIDE

DIRECTION , HARDWARE PROBLEM ,…

2. IF WE HAVE NONE ATTEMPT FROM BOTH SIDE WE FIND OUT THAT

THERE IS MAJOR PROBLEM, LIKE AS : ERROR

DEFINITION NEIGHBORING IN BSC OR THE RELATION IS WRONG AND

SHOULD BE REMOVED

3. IF WE HAVE A LOT OF ATTEMPTS BUT WITH HIGH HANDOVER

FAILURES

WE MUST CHCK INTERFERENCE IN RADIO INTERFERENCE OR CHECK

SYNC ALARM FOR TARGET CELL.




4. IF WE HAVE HIGH ATTEMPTS WITH 100% FAILURE WE MUST COMPARE

CELL DEFINITION IN BSC AND MSC.

5. IF WE HAVE ATTEMPTS WITH HIGH NUMBER BLOCKS WE MUST

CHECK TCH CONGESTION IN TARGET CELL.



ND Report-163:TCH Drop Call Ratio

Contents



Contents

Sample of Report

Explanation Notes

Definitions in Report

CDR Formulas

Example: TR Problem and Solution

Report 163 – TCH Drop - Sample



Report 163 TCH Drop Sample

Explanation Notes



p

ND-Report 163 gives the TCH drop call ratio and the reasons per cell.

With this report we can find the most reasons of drop call in TCH

channel such as RF , ABIS, Transcoder parts.

There is several ways for occupying TCH in a cell: Normal Call Setup,

Directed Retry, FAACH Call Setup and incoming Handover.

Bids means the sum of total TCH occupation in a cell. It depends on the

formula that is using for dcr.

Explanation Notes



p

There is two type of dropped call (call and old):

Dropped call on RF call means that the call on existing TCH will be

dropped because of bad radio condition for example bad Rx-Qual or

Low Rx-Level. This is considered as RF dropped call.

Dropped call on RF old means that the MS wants to take handover

from existing TCH channel to a new TCH channel but it can not take

handover because of bad condition on radio condition. This is

considered as RF old dropped call.

and is same for TR, ABIS and Aif parts.

Report 163 - Definitions



Report 163 – DCR Formulas



p

_ 3 100( & & )

Number of TCH Call Dropped dcr i

Total Number of TCH Channel Setup becauseof Normal Call Setup DRCall Setup FAACH Call Setup= ×

Example: N2990c:Bids= 1008 +130 + 0 = 1138

Dcr_3i= (Total Dropped Call in Bids)/1138= 75.9%

There is 4 formulas for dcr in Report 163. The dcr_3i shows dropped call only

on call setup TCH and my experience shows that dcr_3i should not greater

than 2-3. dcr_4e includes the handover dropped calls too.

Transcoder Fail Problem – Before AMR



B T S N a m e

C a l l

T - T H O

R E - E S S D C C H

R F C A L L

T R C A L L

D R O P R A T I O

N603A 15317 19715 0 1.2 0 2

N2101B 991 18296 0 1.1 0 2

N2229A 1030 12386 0 1.4 0 2

N2230C 292 6967 0 0.8 0 2

N230C 5937 9358 0 1.3 0 2

N2223C 541 9858 0 0.9 0 2

N229B 2794 4068 0 1.2 0 2

N717C 9121 10003 0 1.4 0 2

N603B 12817 21361 0 1.5 0 2

N2603A 985 20005 0 0.6 0 2N230B 1015 503 0 0.7 0 2

N2007B 1156 19658 0 0.7 0 2

N3047A 933 11067 0 1.4 0 2

N455C 7767 8195 0 1.4 0 2

N2101C 842 13801 0 0.6 0 2

N2990A 1729 24778 0 0.5 0 2

N216C 9234 10335 0 1.2 0 2

N2676B 548 0 0 0.2 0 2

N2455A 1401 12920 0 1 0 2

N990B 6483 10675 0 0.9 0 2

N3047B 699 8484 0 0.7 0 2

We haven’t

Transcoder

dropped call

before the AMRactivation.

Transcoder Fail Problem – Before AMR



N219B 11947 15434 0 0.8 0 1

N1047B 5656 4483 0 1 0 1

N101B 5806 5746 0 0.9 0 1

N455A 8623 5745 0 0.7 0 1N990A 16643 22568 0 1 0 1

N2990B 807 0 0 0.4 0 1

N2990C 1129 15365 0 0.7 0 1

N2705A 476 9560 0 1 0 1

N223C 4472 5638 0 0.6 0 1

N223A 3789 5469 0 0.6 0 1

NM113A 226 23 0 0 0 1

N2705B 1784 18701 0 0.5 0 1

N676B 5490 6270 0 0.5 0 1

N717A 8683 7322 0 0.6 0 1

N219C 10681 0 0 0.7 0 1

N2705C 751 8018 0 0.4 0 1

N101A 5843 4729 0 0.4 0 1N223B 4463 10067 0 0.5 0 1

N2603C 416 15694 0 0.7 0 1

Transcoder Fail Problem- After AMR



B T S N a m e

C a l l

T - T H O

R E - E S S D C C H

R E - E S T C H

R F C A L L

R F O L D

T R

C A L L

D R O P R A T I O

N 2216B 1375 23951 0 0 5.8 2 .4 22 .6 31

N 2455A 1764 14135 0 0 0.4 0 .7 21 .6 23N 2603C 2245 19857 0 0 0.2 0 .5 13 .3 14

N 2219C 880 13798 0 0 1 1 .4 11 .4 14

N 717B 14898 17235 0 0 2.1 0 .9 11 .3 15

N 2603B 1521 23705 0 0 0.4 0 .2 10 .7 11

N 2990A 1747 20819 0 0 0.4 1 .4 10 .5 12

N 2216C 744 13451 0 0 1.1 1 10 .1 12

N 2705B 1099 15566 0 0 0.8 1 .2 7 .6 9N 2717A 991 12306 0 0 1 1 7 .2 10

N 2990B 570 17485 0 0 0.9 1 .4 6 .4 8

N 2717B 1375 15281 0 0 3.1 1 .3 6 .3 11

N 229A 12611 19020 0 0 1.8 0 .5 4 .9 7

N 2219A 838 19179 0 0 1 2 .4 4 .6 9

TCSM 112 was SE-NH but it's ET was working. We

change the state of ET to SE-NH.

The most

dropped call isbecause of

Transcoder

problem after

the AMR

activation.

Transcoder Fail Problem-After Solution



Transcoder

dropped call

resolved withblocking the

faulty TCSM. It

affected normal

Half-Rate so

much. (Rep-204)

Transcoder Fail Problem-After Solution



Contents





Advantage of ND 166


Information




With this report we can analyze the sdcch drop ratio in

details and understand which part has the most effect

in drop of sdcch channels in network. Abis and RF are the most common reason for sdcch

dropped call.

In a optimised network, sdcch dropped call must be below 10% in nokia system.




Reasons for sdcch dropped call:

TRX problem: whole TRX or Time Slot that SD channel is placed on it may be has faulty. We can check with MML command ZEOL to check the

TRXs. We can change the location of sdcch channel and change the faultyTRX.

Abis link problem: We can check with MML command ZYMO. O&M teamshould solve the link problem.

Interference: We should check frequency plan of network and check Report-

196 for interference.

A-Link Problem: sometimes bad connectors on BSC or MSC side or somemismatches maybe cause A-Interface fail on SDCCH. O&M and MSCteams should solve the problem.

Report 166 – High SD Drop and Solution



• N990B had high Sdcch drop ratio

• 1 Sdcch/8 was on TRX-8 and TRX-8 had alarm

We changed the position of Sdcch/8 from TRX-8 to TRX-2



ND Report-204:

NETWORK BENCHMARK

STATISTICS

Contents





Advantage of ND 204


Information

Description



This Report shows BSC wise KPI’s and PI’s.

SDCCH Failure, TCH Failure, SDCCH Drop, TCH Drop, TCH

Traffic, TCH Codecs, HO Causes, HO Success and Failure, RX-Quality , …

We can find in a look that which part has problem: for Example

if A-interface or ABIS interface has problem, we can see

immediately in this report.

SDCCH Channel



TCH Channel



TCH Codec Versions



Handover Causes



UL, DL QUALITY/LEVEL DISTRIBUTION



UL, DL QUALITY DISTRIBUTION PER CODEC



Expeirence: Transcoder Fail in B026N



UL, DL QUALITY DISTRIBUTION PER CODEC



Expeirence: CSSR Problem in B067N



ND Report-073:Undefined Adjacent

Cells

Contents



1. SAMPLE OF REPORT

2. DESCRIPTION

3. ADVANTAGE

4. ANALYS

5. EXPERIENCES

6. INFORMATION




NCC Nework Colour Code of UAC.

BCC Base Sation Colour Code of UAC.

BCCH BCCH carrier number (ARFN) of UAC.

Per dura Average period duration.

Nbr of per Number of periods.

Nbr of samples Nbr of samples for calculating the average

DL signal strength (*100).

Avg DL sig str Average DL signal strength received from UAC. Sort factor Sorting factor (average level)/1000




This report can be used to check the network plan for

adjacencies,complete analyzation rep 153 and checkinterference.


hi i ll d fi d dj ll AC ( ll d b S



This report gives all undefined adjacent cells UAC (cells measured by MS but not defined as neighbour of the serving cell) for all BTSs in the selectedarea.

If "Active BA list = adjacent cell definitions) or If "Active BA list = idle

BA list = 0" (active BA list = adj. cell definitions), BSC uses adj. celldefinitions when it matches the BA indexes and the BCCH. If "Active BAlist = idle BA list = list 1", BSC uses "list 1" when it matches the BAindexes and the BCCH.

Undefined cells measurement is an optional feature in the BSC.

UACs with good signal strength and large number of samples are important.

Other reports that can be used to check the network plan for adjacencies are070,071,072,074,075.


Undefined adj cells (UAC)



BCCH=BCCH of DAC

BSIC<>aa

Undefined adj cells (UAC)

Serving cell BA List=A

BCCH<>one freq of A

Rep 073 cangive this UAC

Defined adj cell (DAC)BCCH=one freq of A

BSIC=aa

BCCH=BCCH of DAC

BSIC=aa

Rep 073 cannot give this

UAC butRep 153 canshow HO failin this BCCH

MS can notmeasure this cellRep 073 can notgive this UAC

Experiences



1)N2254C - sample that indicates problem in neighbour definition and

interference in BCCH frequency

2)NM861B - sample that indicates sector swap

3)N2255A - sample that is not important

Sample 1: problem in neighbour definition and interference in

BCCH frequency




BCCH frequency



UAC: N254A

BCCH=124,BSIC=10

Serving cell:

N2254C

DAC: N097C

BCCH=124,BSIC=16

Sample 1: Neighbours of N2254C (EAO)

BCCNCCFREQNeighbourSource BTSBSC



41107 N694BBTS-168 N2254CB023N

01119 N694ABTS-168 N2254CB023N

41123 N261CBTS-168 N2254CB023N

72113 N254CBTS-168 N2254CB023N

62117 N254BBTS-168 N2254CB023N

61607 N2460BBTS-168 N2254CB023N

31608 N2261CBTS-168 N2254CB023N

61599 N2254BBTS-168 N2254CB023N

11603 N2254ABTS-168 N2254CB023N

21590 N2124BBTS-168 N2254CB023N

21605 N2124ABTS-168 N2254CB023N

41587 N2097CBTS-168 N2254CB023N

77606 N2048CBTS-168 N2254CB023N

11613 N2048BBTS-168 N2254CB023N

32116 N124BBTS-168 N2254CB023N

62108 N124ABTS-168 N2254CB023N

72110 N1161CBTS-168 N2254CB023N

61124 N097CBTS-168 N2254CB023N

Sample 1: Find BCCH=124,BSIC=10 from parameter general cell



10124BTS-030 N435BB021N

10124BTS-024 N254AB023N

BSICBCCHBTSBSC


BCCH frequency



N097C Defined adj cell

BCCH=124 BSIC=16

N254A Undefined adj cell

BCCH=124 BSIC=10

Serving cell

N2254C

Sample 2 : problem in hardware (sector swap) but not in neighbour

definition




definition



GC site


definition

BCCNCCFREQNeighbourSource BTSBSC



26112BTS-010 N1082CBCF-004B075N

26112BTS-034 N419BBCF-012B066N

26112BTS-115 N033ABCF-011B023N

BSICBCCHBTSBCFBSC

42100BTS-194 NM861BB023N

7295 NM861ABTS-194 NM861BB023N

32105 NM094BBTS-194 NM861BB023N

31103 NM017ABTS-194 NM861BB023N

52109 N255CBTS-194 NM861BB023N

02607 N2205CBTS-194 NM861BB023N

02597 N2205ABTS-194 NM861BB023N

51124 N205CBTS-194 NM861BB023N

32112 N205BBTS-194 NM861BB023N

31118 N205ABTS-194 NM861BB023N

41610 N2033BBTS-194 NM861BB023N

21122 N033BBTS-194 NM861BB023N

NM861B

Neighbours

All cells withBCCH=112,BSIC=26

Sample 2 : problem in hardware (sector swap) but not in neighbour definition



()00000000 NM861BB023N

BSC(####140705213000000 NM861BB023N

B023 NM094B227275215000000 NM861BB023N

B023 N205B230975215000000 NM861BB023N

B023 N2205A4309752152500000 NM861BB023N

B023 N205A13097521530335002 NM861BB023N

B023 N2205C63097521562152320141 NM861BB023N

B023 N205C3309752157752390143 NM861BB023N

B023 NM017A166735215219724339360 NM861BB023N

B023 N033B2215352151139192101826 NM861BB023N

B023 N2033B5215352157358341102692 NM861BB023N

B023 NM861A16092521519321471716536 NM861BB023N

Target BSCTarget CellCILACATTBLK FAILFAILBLK ATTSource CellBSC ID


definition



Sector swapin NM861A,B

Sample 3 : There is no problem in neighbour definition



N2255A

Neighbours

Target BSCTarget CellCILACATTBLK FAILFAILBLK ATTSource CellBSC ID




B023 N234C32147521500010001 N2255AB023N

B023 N694A1280952150002005 N2255AB023N

B023 N254C35207521524171511018 N2255AB023N

B023 N2694A42809521500011358 N2255AB023N

B023 N254A1520752155390460109 N2255AB023N

B021 N560B22726521000050254 N2255AB023N

B021 N2560B527265210000224479 N2255AB023N

B023 N1161B230335215132721310751 N2255AB023N

B023 N255B252105215298115430883 N2255AB023N

B023 N255C3521052152293165901082 N2255AB023N

B023 N1161A1303352152892203101303 N2255AB023N

B023 N124C3215952152325152301847 N2255AB023N

B023 N124B2215952153772173102612 N2255AB023N

B021 N2422B5522752100003553026 N2255AB023N

B023 N2255C65210521565157411683583 N2255AB023N

B023 N2255B552105215143818613787434 N2255AB023N

B023 N2124B52159521559707621758882 N2255AB023N

B023 N255A1521052152254422213013884 N2255AB023N



Call Setup Scenario:

ND Reports & Formulas

Contents



1. Call Setup Scenario in MOC

2. ND formulas for Call Success

3. ND Reports for Call Success

4. MCI Formulas in KPI

5. Information



Signalling in MOC Call Setup - General

1. Immediate assignment (RACH & AGCH)



g ( )

2. Service Request (SDCCH)

3. Authentication (SDCCH)

4. Ciphering mode setting (SDCCH)

5. Call initiation (SDCCH)

6. Assignment of traffic channel (SDCCH & FACCH)

7. Call confirmation (FACCH)

8. Call accepted (FACCH)

Signalling in MOC Call Setup - 1



Traffic channel access and success

The overall call success is the product of the following

f



factors:

SDCCH access

SDCCH success

TCH access

TCH success

Network Doctor Reports shows the situation at each part

in BTS or Area level.

ND Formulas for Call Success

csf_1 (SDCCH access probability, before FCS)

csf_1a (SDCCH access probability, after FCS)



csf_2a (SDCCH success ratio)

csf_2e (SDCCH success ratio)

csf_2j (SDCCH success ratio)

csf_2m (SDCCH success ratio)

csf_2n (SDCCH success ratio)

csf_3i (TCH access probability without DR)

csf_3l (TCH access probability, real)

csf_3m (TCH access probability without DR and Q)

csf_4u (TCH success ratio, area, before call re-establishment)

csf_4x (TCH success ratio, BTS, after call re-establishment)

SDCCH access probability

Gives the probability to access SDCCH. Applicable for area

and BTS level..A low value means high traffic on SDCCH and



lack of SDCCH resources, that is SDCCH blocking.

Before FACCH Call Setup:

After FACCH Call Setup:

SDCCH success ratio

The formula does not separate the SDCCH call seizures from otherseizures (such as LU). The failure rate in the case of a call or LU can greatly

differ from one another, wherefore you cannot use this formula for SDCCH



call success ratio calculation.

It is not exactly known how large a share of sum (sdcch_abis_fail_call +sdcch_abis_fail_old) really are setup failures. Most of them are because of

Ghosts.

The best values seen are around 98%.

SDCCH success ratio

Includes A interface blocking.

Suitable for BTS level



Suitable for BTS level.

TCH access probability

This PI indicates what would be the TCH blocking if DR was not used.

Does not contain the congestion of the A interface circuit pool



Does not contain the congestion of the A interface circuit pool.

TCH success ratio

Before Re-Establishment:



After Re-Establishment:

ND Reports for Call Setup

ND Report 250




ND Report 251



We can use different formulas for Reports 250 &251(csf_1, csf_1a and so on)


ND Report 207This report provides 10-day profiles of the indicators listed below.



- SDCCH availability

- SDCCH usage

- TCH availability

- TCH usage

- TCH traffic

- SDCCH access probability

- SDCCH success ratio

- TCH access probability

- TCH success ratio


ND Report 207




ND Report 204



ND Report 130 – SDCCH Congestion



ND Report 135 – TCH Congestion



ND Report 181- TCH Traffic Profile



Formula



SDCCH Congestion formula in MCI KPI



100*(SDCCH_BUSY_ATT - TCH_SEIZ_DUE_SDCCH_CONG) / SDCCH_SEIZ_ATTSDCCH cong

SDCCH Congestion = (1 – SDCCH access probability)*100 =100- csf_1a

CSSR formula in MCI KPI

(100-SDCCH Cong) *(TCH NEW CALL ASSIGN+TCH RE EST ASSIGN-BSC I SDCCH TCH-



(100 SDCCH Cong) (TCH_NEW_CALL_ASSIGN TCH_RE_EST_ASSIGN BSC_I_SDCCH_TCH

MSC_I_SDCCH_TCH+MSC_O_SDCCH_TCH+BSC_O_SDCCH_TCH) /

(SDCCH_RE_EST_ASSIGN+SDCCH_NEW_CALL_ASSIGN-SDCCH_SMS_ASSIGN)

CSSR

CSSR= (SDCCH Access Probability) * (SDCCH Success Probability) *

(TCH Access Probability) = csf_1a * csf_2a * csf_3

ND formulas for performance evaluation

Nokia defined several formulas for Call Success

factors (SDCCH & TCH). So Optimisation engineers

i i f f l k



can investigate performance of several network

elements and features. For example, we can see the

effect of Directed Retry or Queuing features on Call

Setup Success Rate.

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