Basic Knowledge for Optimiser

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General information1. Normal assignment = MTC and MOC

MOC = Mobile Originating Call : Request for calling

MTC = Mobile Terminating Call : Request for answering call

2. TCH assignment = Normal assignment + Incoming Handover assignment

3. Attempt = Request success with no blocking

4. Blocking = Attempt not success

5. Failure = Attempt success but not occupy

6. Drop = Loss of connection

7. Success = Calculate since request

8. EFR = Calculate since attempt success

Note: EFR = Ef ficiency Rate

9. Handover = Changing to new TCH channel in same cell or other cell which has good radio condition or special case

dB Transformation for Power and Voltage

dB Power dB Voltage Ratio Approximated value

6 12 x 3.98 4

5 10 x 3.16 3.2

4 8 x 2.51 2.5

3 6 x 1.99 2

2 4 x 1.58 1.6

1 2 x 1.26 1.3

0 0 1 1-1 -2 / 1.26 1.3

-2 -4 / 1.58 1.6

-3 -6 / 1.99 2

-4 -8 / 2.51 2.5

-5 -10 / 3.16 3.2

-6 -12 / 3.98 4



dB Power dB Voltage Ratio Approximated value

. . . .

. . . .

1000 2000 1000 1000

100 200 100 100

. . . .

. . . .

20 40 20 20

10 20 10 10

0 0 1 1

-10 -20 -10 -10

-20 -40 -20 -20

. . . .

. . . .

-100 -200 -100 -100

-1000 -2000 -1000 -1000

. . . .

. . . .

Power (dB) = 10 log P P = 10^(Power (dB)/10)

Voltage(dB) = 20 log V V = 10^(Voltage (dB)/20)

dB is the difference of level but dBm is the unit in dB with reference from 1 milliwatt so we cannot use dBm to explain the

difference of level e.g. the different power between TRE 1(40 dBm) and TRE 2 (42 dBm) is 2 dB.

EIRP (Effective Isotropic Radiated Power) = Radiation power from Antenna with reference to Isotropic point source.ERP (Effective Radiated Power) = Radiation power from Antenna with reference to Dipole antenna.

EIRP = ERP + 2.15 dB

(Antenna)Gain = Maximum power in direction of maximum directivity.

Beam width (HPBW) = Width of antenna pattern at - 3 dB power decrease in direction of

maximum gain.



Radio measurement

Rx Quality Rx level

Level Value in OMC-R Average BER Range of BER Power(dBm) FS(dBuV/m) Level number

0 14 0.14 <0.2 -110 27 0

1 28 0.28 0.2-0.4 -109 28 1

2 57 0.57 0.4-0.8 -108 29 23 113 1.13 0.8-1.6 . . .

4 226 2.26 1.6-3.2 . . .

5 453 4.53 3.2-6.4 . . .

6 905 9.05 6.4-12.8 . . .

7 1810 18.1 >12.8 -49 88 61

Color Power (dBm) -48 89 62

Brown -65 to -10 -47 90 63

Red -74 to -65Yellow -82 to -74

Green -92 to -82

Grey -106 to -92

Note:

1. Color bar is reference from drive test criteria (North Region)

2. Worst Rx quality is level 7.

3. Power (dBm) = 10 log (P/1mW)4. BER = Bit Error Rate

5. FS = Full ScaleStandard C/I =

Standard C/A =



Interference band (Noise signal strength effecting to C/I)

Logicalname

HMI name B8 DefaultTAO_Macro

(B8)TAO_Micro

(B8)TAO_Indoor

(B8)Unit

INTFBD1Interferencebands 1-2 limit

-100 -100 -100 -100 dBm


-95 -95 -95 -95 dBm


-90 -90 -90 -90 dBm


-85 -85 -85 -85 dBm

INTFBD5Interferenceband 5 upperlimit

-47 -47 -47 -47 dBm

Interference can be from internal (512-574) or external (e.g. microwave, other PLMN).

Example : Noise level is in interference band 3 and RF signal level from serving cell is -85 dBm then C/I = 15 dB.

Microwave modulation

DXR 16 QAM

XP-4 QPSK

Eclipse 16 QAM

Note: QAM can check constellation to confirm Power distribution in each phase



Upgrade work

UATRX Simple TRX upgrade

UASC Add second cabinet upgrade

UADO Double antenna upgrade

UADA Double antenna upgrade with second cabinet

UBAT Battery upgrade

UREC Rectifier module upgrade

UCANT Change antenna upgrade

UDON FSR upgrade phase SP11

Address mapping between OMC-R and BTS terminal program

Address of hardware in BTS cabinet=>Trad/Tadh uses 3 slots 1(81) 4(84) 7(87) 10(90) TREs Shelf 5 80

=>ANCD uses 4 slots 3(67) 7(71) ANCDs Shelf 4 64

=>SUMA uses 2 slots 1(49) 4(51) 7(55) 10(58) TREs Shelf 3 48

=>Trdh uses 4 slots 3(35) 7(39) ANCDs/SUMA Shelf 2 32

1(17) 4(20) 7(23) 10(26) TREs Shelf 1 16

See in Note

1 4 7 10

Address 1,2,7,10 For TRE

Address 3,11 For ANCAddress 7,11 For SUMA

Standard

Note: Add to default address as below to find real address in BTS terminal program



MOC (No failure)

TEMS Comment GSM Standard Comment

1.Call AttemptChannel RequestNote: MS1

1.Radio LinkEstablishmentPhase

RACH for SDCCHNote : MS2 attempt to response Paging message

2.Dedicated Mode BCCH & BSIC 2.Since SDCCHphase

Use SDCCH for TCH assignment request

3.Call Setup Alerting3.Alert andConnecting phase

After TCH assignment complete sent from BSC toMSC in TCH assignment phase or TCH assignmentcompleted (No blocking or failure)

4.Call Establishment Connect Acknowledge4.Alert andConnecting phase

After received Alerting signal and connecting signalfrom MSC,MS will send connected acknowledge back to MSCthen the conversation begin



Call Complete/No drop:CCRRequest (RACH) for Traffic channel(Mobile Originating Call :MOC)

Sdcch blocking( No available SDCCHresources )

Immediate Assignment(AGCH)

Assignment fail SDCCH

Attempt(Assignment success)

SDCCH PhaseDrop SDCCH

No TCH resources TCH assignment blocking

TCH assignment TCH assignment failure

TCH assignment success

C S S R

Using TCH channel

Request new channel(Same cell/Other cells)

Drop by radio condition or BSS problem

Changing to next TCH channel(Handover)

1-Drop between handover2.Handover failure

3.Handover blocking4.HO drop

Occuply new channel(No blocking, failure and drop)

Drop by radio condition or BSS problem

H

O S R

C

D R

( R L T / H O / B S S )

Call end by normal release CSR/CCR: No call drop



During call:CDR

After TCH assignment success

Radio condition

Drop due to radio link failureTCH drop radio

Hardware Problem

Radio conditionDuring handover

(Cannot Retune to old channel) TCH drop HO

Hardware Problem

TCH drop BSS internalSome HW problem in BSS part

(Excluding Transcoder)

TCH drop BSS RTC

1.Faulty MT120 card (RTC)2.Transmission network problem3.Faulty TRE4.RSL error5.Faulty TCU

Call handle on Traffic channel

T y p e o f C a l l D r o p

BSS problem(Connection lossafter Air interface)

Call Completed/No drop call: Normal release

Radio condition: 1. Coverage (Downlink) 2. Frequency (Interference) 3.Unbalance PBGT (Uplink)



Assignment call:CSSRNo Sdcch resource due to HW

failure

No Sdcch trafficCannot allocate SDCCH

Congestion on sdcch channel

Sdcch immediate assign block

Sdcch assign fail radioDue to radio conditon(Include

HW

problem for Motorola)

Sdcch assign fail BSS Due to BSS problem

Request for SDCCH

Sdcch immediate assignment failure

Sdcch drop radio Due to radio condition

Sdcch drop HO: not activate now

Sdcch drop BSS Due to BSS problem

SDCCH assignment success Sdcch drop



Cannot allocate TCHSector locked or hardware

locked

TCH assign blocking(Congestion on TCH channel) No TCH resource available

TCH assign fail radio Due to radio condition

TCH assign fail BSSPreparation phase

TCH assign fail BSS_internal

TCH assign fail BSS_RTC

TCH assign failure

TCH assignment success =>Call Setup Success (No any failure)<=



Handover Process: HOSR

Relate withincoming HOblocking

No new TCHchannel

at target cell

High traffic at targetcell

Cannot allocate new TCH channelRequest for new TCH channel



Hardware problem

at target cell

Co BSIC&BCCHRelate with

incoming handoverfail radio

Interferenceat target cell

Handover failure Reverse toold

channel

HOdrop radio

RF lossbetween handover

Handover drop(HO cmd sent but no HO accesss)

HOdrop BSS

BSS problembetween HO

Handover notsuccess

(Only outgoing)

Request success/Handover is inprogress

Handover notsuccess both inand out in every

sectors

Handover failure both incoming andoutgoing beween source and target

(two ways)

Incoming handover fail andoutgoing handover ROC at the

same time

in every sectors

Hardware problem(Processer unit)

Occupied new TCH at target cell Handover success



Minor KPI Comment KPI

SDCCH(Signalling channel in Idle mode) From idle mode to dedicated mode

SDCCH Assignment request

SDCCH (immediate) assignment blocking Cannot assign/no SDCCH resource

SDCCH (immediate) assignment failure (Radio) Assignment is in progress but radio problem occur

SDCCH (immediate) assignment failure (BSS) Assignment is in progress but BSS problem occur

SDCCH Assignment completed Remains in SDCCH channel.

SDCCH drop (Radio) Assigned SDCCH but radio problem occur

SDCCH drop (BSS) Assigned SDCCH but BSS problem occur

SDCCH drop (HO) Not activate now

TCH(Traffic Channel) From SDCCH to TCH with no SDCCH drop

TCH Assignment is in progress

TCH assignment blocking Cannot assign/no TCH resource

TCH assignment fail (Radio) Assignment is in progress but radio problem occur

TCH assignment fail (BSS) Assignment is in progress but BSS problem occur

TCH assignment fail (PREP BSS) Not include BSS problem and congestion problem

C a l l S e t u p

S u c c e s s R a t e ( C S S R

)

TCH Assignment completed Occupied TCH channelTCH drop (Radio) Radio problem occur while handle call in dedicated mode

TCH drop (BSS_INT) BSS(internal BSS part) problem occur while handle call in dedicated mode

TCH drop (BSS_RTC) BSS (Transcoder) problem occur while handle call in dedicated mode

TCH drop (HO) Drop while handover from source to target cell C a l l D r o p R a t e ( C D R )

Changing TCH channel/HandoverReselect new traffic channel due to better or conditionfrom handover cause split

Outgoing handover fail ROC(Reverse to Old Channel)Cannot occupy new traffic channel due to failure at target cellbut no drop (can return to old source cell)

Outgoing handover drop Cannot occupy new traffic channel and drop, radio is the main cause

Outgoing handover fail no alloc(not allocate new TCH)Cannot occupy new traffic channel due to no TCH resource at target cell

Outgoing handover fail BSS Cannot occupy new traffic channel due to BSS problem H a n d o v e r

S u c c e s s R a t e ( H O S R )



Main KPI Counter

1.Traffic channelTCH assign failure

TCH assign fail radio =>MC746B

TCH assign blocking =>MC812

TCH assign fail prep BSS =>MC140A-MC140B-MC812

TCH_HO_Succ => MC642+MC652 (Ext HO+INT HO): Incoming HO success

TCH_Ass_Succ => MC718: Normal assign success per TRX (MOC)

Call drop

Call drop radio (RLT) =>MC736

Call drop BSS_RTC =>MC739

Call drop BSS_INT =>MC14C

Call drop HO =>MC621

2.SDCCH channel

SDCCH assign failureSDCCH assign fail radio =>MC149

SDCCH assign blocking => MC04

SDCCH drop

SDCCH drop radio => MC138

SDCCH drop HO => MC07

SDCCH drop BSS => MC137



Basic concept



SDCCH Template

#TRX STD(Normal) ADD(Extended) STDDYN(Normal Dynamic) ADDDYN(Extended dynamic)

1 8 Static 8 Static 8 Static 8 Static1 TRX can have only 1 SDCCH

timeslot

2 8 Static 16 Static 16(Standard+new 8 dynamic) 16 Static Normal Dynamic

3 16 Static 24 Static 24(Standard+new 8 dynamic) 24 Static Normal Dynamic

4 16 Static 24 Static 24(Standard+new 8 dynamic)32(Normal dynamic/static+new 8

dynamic)Extended dynamic









Same number of SDCCH but difference

functional

Condition for SDCCH configuration.

SDStatic SDCCH (Config with odd TRX e.g. TRX 1, 2,3etc.)

SDExtended SDCCH : Add more due to not enoughSDCCH

Dyn SD Standard dynamic SDCCH (Normal dynamic)Dyn SD Extended dynamic SDCCH



SDCCHconfiguration

Number of TRX TS definition for micro and macro cell

TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7 TRX_PREF_MARK

1 TRX TRX 1 BCC TCH TCH TCH TCH TCH TCH SD 0

TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7


TRX 2 Dyn SD /SD TCH TCH TCH TCH TCH TCH TCH 0




TRX 3 SD TCH TCH TCH TCH TCH TCH TCH 0





TRX 4 TCH/ Dyn SD TCH TCHTCH TCH TCH TCH TCH 0

TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7 5 TRX TRX 1 BCC TCH TCH TCH TCH TCH TCH SD 0








6 TRX TRX 1 BCC TCH TCH TCH TCH TCH TCH SD 0TRX 2 Dyn SD /SD TCH TCH TCH TCH TCH TCH TCH 0




TRX 6 TCH TCH TCH TCH TCH TCH TCH TCH 0


7 TRX TRX 1 BCC TCH TCH TCH TCH TCH TCH SD 0TRX 2 Dyn SD /SD TCH TCH TCH TCH TCH TCH TCH 0






TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7 8 TRX TRX 1 BCC TCH TCH TCH TCH TCH TCH SD 0










TMA concept

TMA is using for amplifier Rx level from mobile (MS) in uplink path.

TMA help to improve call drop due to radio condition (low UL level) and also improve TCH assignment both normal

assignment (MOC/MTC) and incoming handover.

However TMA not help for cell which has no uplink level problem, by the way the downlink level will be decreased from

TMA.



BTS cabinet for Indoor

MBI 3 => 8 TRXsMBI 5 => 12 TRXs



BTS cabinet for Outdoor

MBO 1 => 8 TRXs

MBO 2 => 12 TRXs



There are 2 modes for TRX configuration with ANC, one is Non-combining mode or Low loss mode and another one is

Combining mode.The first one is using for configuration up to 2 TRXs and another one is using for configuration up to 4 TRXs (Per 1 ANC).

1. Configuration for low loss mode.

2. Configuration for combining mode.



1. Low loss configuration loss 1.8 dB.

Note: For 1 ANCD and TRE up to 2

2. Combining configuration loss 5.1 dB.

Note: For 1 ANCD and TRE up to 4



Data from Site Inspection work.

EDGE type TREs which are Tadhe and Trade help improve TX power in DL.



Micro BTS configuration



Basic knowledge to analyze BTS hardware problem.



BSS Abbreviation



Reference: 1.GSM_Trouble_Shooting.xls 2.Alcatel BSS Description.pdf 3.PM Counters.pdf 4.B8Clist.pdf 5.BSS Telecom Parameters.pdf

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