HUAWEI - statistics data analysis and optimization V 4.0.ppt

8/10/2019 HUAWEI - statistics data analysis and optimization V 4.0.ppt

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Statistics Data Analysis

and Optimization V4.0

for HUAWEI GSM/GPRS/EDGESystem

Compiled by Jin/Jiangxin

E-mail: [email protected]

2008/5/8


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Chapter 1 GSM system

1. Work items in an optimization project2. Review of the GSM system

3. Based technology in GSM system

4. Drive test and analysis

5. Parameters in common use

6. OMCR statistics data and the formula in common use7. Main methods in the performance analysis procedure

8. Selection and reselection

9. SDCCH congestion

10. TCH congestion and drops

11. Call progress introduction in common use12. Power control algorithm

13. Handover algorithm

14. Cases according to statistics data

course contents


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9. SDCCH congestion






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Work items in optimization

Find the problems Statistics data

DT and CQT Alarm check

Custom complain

Analysis the problems Statistics analysis

DT and analysis

Alarm analysis

Call process analysis

Frequency plan and reuse

Solve the problems Trouble shooting

Improve coverage

Adjust TRX configuration

Adjust antenna system

Edit freq.plan table

Neighbor relations Parameters

Checking and compare results Before and after modify

Different BSC/Cells

Different network

Problems in network Hardware trouble problem

Freq. interfering problem Coverage problem

HO relations problem

busy or idle problem

Traffic balance

Underlay and overlay problem

KPI

Wireless parameter problem

Especial problems

(access,roaming,crossed talk,A-interface .)

Steps for problem Find the problems

Analysis the problems

Resolve the problems

Checking and compare resultsare throughout the optimization process.


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Emphasis of the optimization

System performance

Access

Channel success

Congestion

Drop

Handover

Traffic

Quality

Coverage

Frequency

1. Immediate assignment rate

2. CSSR3. Wireless access rate

4. Sdcch success rate

5. Sdcch congestion rate

6. Sdcch drop call rate

7. Tch success rate

8. Tch congest rate

9. Tch drop call rate(including HO)

10. Tch drop call rate(excluding HO)

11. Ho success rate(from attempt)

12. Ho success rate(from command)

13. SD/TCH traffic14. TCHF and TCHH traffic balance

15. Overlay and underlay traffic balance

16. Coverage rate (DT)

17. BER/MOS


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Output coverage chat,congestion rate,drop

calls,interfering area according to the DT data.

And optimize frequency, adjust channels in the

congestion cells and concentric lay, adj. parameters

Check and optimize the neighbor relation, correct

neighbor data (internal and external neighbors)

Optimize parameters( general)

Put in suggestions and good plan

Optimization summarize and

technology communion

Optimization flowing(2)

Coverage, frequency,

channels, configuration,parameter

Neighbor relations

optimization

Optimize parameters

compare the performance

and put in suggestions

Optimization

summarize


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9. SDCCH congestion






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PSTN Network

Billing Center

GBTS

TE

MT

MS

GBSC

Internet

A

Pb

Um

Gi

GSM network review

HLR/Auc/EIR

SMS-GMSC/IWMSC

MSC/VLR

SS7 Network

GSM Core Network

GGSN

CG

SGSN

DNS

GPRS Backbone

GbGb

Gs

Abis

Um

GPRS Core Network

EDGE PCU

OMC


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FAN BOX

SWITCH BOX

FAN BOX

AIR BOX

AIR BOX

P

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D

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TDU

Common

equipment

TRXCDU

air/fan

Review of BTS312

CDU: Combiner & Divider Unit

TRX: Transceiver Module

PMU: Power Monitoring Unit

TMU: Timing/Transmission & Management

PSU: Power Supply Unit

TES: Transmission Extension power Supply

TEU: Transmission Extension Unit

TDU: Time Distribution Unit


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Function:

Core of site

Timing

Transmission

Management

BSC

External synchronous clock

MMI man-machine

interface

External

Alarmingcontrol

BIU

OMU

EAC MCK

Standby MCK

Extended BIU

DBUS Internal data bus

CBUS Internal control bus

TDU Internal

clock bus

TMU


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Combiner

Distributor

Distributor

Coupler

TX1

TX2TX-COMB

TX-DUPRX1RX2RX3RX4

HL-out

RX2RX3RX4

RX1

HL-in

RXD

TX/RX-ANT

RXD-out

CDU

In common use way:2TRX+1CDU: TX-COMB and TX-DUP ,HL_in and RXD-out connected

2TRX+2CDU: TX-COMB and TX-DUP connected or not connected( less loss)

4TRX+2CDU: TX-COMB and TX-DUP connected

6TRX+1SCU+1/2CDU: TX-COMB and TX-DUP ,HL_in and HL_out connected

8TRX+2SCU+1/2CDU: TX-COMB and TX-DUP ,HL_in and HL_out connected

Especially the TX_out can be connected with TX_DUP and it can decrease 3db of

combination loss.


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Distributor

CouplerTX1

RX1RX2

TX/RX-

ANT1

Distributor

CouplerTX1

RX3RX4

TX/RX-

ANT2

EDU and SCU

SCU: no coupler

Four carriers are combined

output through 2steps of 3dB bridges

plug loss is 6.8dB.

EDU: No combined loss


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Review of BTS3012

DPU: Digital Power Unit

TRU: Transceiver Unit

PMU: Power Monitoring Unit

TMU: Timing/Transmission & Management

Principle for RF send and receive mode:

Send: combining when TRU combined actually

no combining when TRU not combined actually

Receive: dividing receiver when TRU combined

indepandent receiver when TRU no combined


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Access link check

Dual polarization

antenna

TTA

option

Lightning arrester

BTS rack

Jumper

connector(DIN)

DINconnector Lightning arrester/feederconnector(DIN) Jumper/TTA

Connector (DIN)jumper

Jumper/TTA

connector(DIN)

Antenna

Connector(DIN)

FAN BOX

SWITCH BOX

FAN BOX

AIR BOX

AIR BOX

P

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TDU

Inside jumper

TRX jumper

TX and RDX cables


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9. SDCCH congestion






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Um layer

Communicate MNG(CM)

Radio resource (RR)

Mobility MNG(MM)

CPU

RACH BCCH AGCH/PCH SDCCH SACCH TCH FACCH

TCH0 TCH1 TCH2 ..SACCH ..TCH24 IDL

Multi-frame

Phy. link layer(L1)

Data link layer(L2)

Application layer(L3)


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CM

MM

RR

LAPDm

SigL1

L3

L2

L1

MS

RR BTSMLAPDm

SigL1

LAPD

SigL1

LAPD

SigL1

BTSM

RR

SCCP

MTP

BSSMAP

CM

MM

BSSMAP

SCCP

MTP

MSCBSCBTS

Um AAbis

GSM protocol stake


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Speech/channel coding

Speech A/D8KHz, 260bit

Speech codeSection

20ms13kbit/s

Channel code

Interleaving Burst pulseCipher

22.8kbit/s,456 bits,20ms

Modulate33.8kbit/s

transmission

Speech coding :

Coding type: RPE-LTP

sampling 8Khz,and 20ms/frame,in each frame there are 4 sub-frame

then get a rate of 13kbit/s.

260bits/20ms=13kbit/s

Channel coding:

456bit/20ms=22.8kbit/s

From 260 bits to 456 bits in a speech frame

Parity check 3bits Convolution

Coder

50bit*2

132bit

78bit

456bit

Tail 4bits


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Interleave

1 2 3 4 5 6 7 8 ... ...452 453 454 455 456

Block

8

16

.

.

.

456

2

10

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450

6

14

.

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454

1

9

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449

4

12

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452

7

15

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455

3

11

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.

451

5

13

.

.

.

453

.... ....

B0 B1 B2 B3 B4 B5 B6 B7

{A4,B0} {A5,B1} {A6,B2} {A7,B3} {B4,C0} {B5,C1} {B6,C2} {B7,C3}

Rectangular interleave

Diagonal interleave

456bit/8=57bit/frame

Two type of interleave: rectangular type and diagonal type


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Frame structure and burst frame

0 1 2 3 2044 2045 2046 2047

0 1 2 3 48 49 5047

0 1 24 25

0 1 24 25 1 49 500

0 1 4 5 762 3

TB3

TB3

GP8.25

TB: Tail bitTB3

TB3

GP8.25

GP: Guard period

TB3

TB3

GP8.25

TB

3

TB

3GP 68.25

58 information bits 26 TSC 58 info bits

Constant bit 142

Info bit 39 Extended TS 64 Info. bit 39

sequence 41Info bit 36

Normal burst (NB for traffic)

Freq correct burst(FB for

for freq synchronization)

Sync burst (SB for time sync)

Access burst (AB for access)

1 hyper frame(for hopping FN)=2048 super-frames=2715648TDMA frames (3 hours, 28 minutes, 53 seconds and 760 milliseconds)

1 super-frame=1326TDMA frames (6.12 seconds)

1SACCH multiframe=26TDMA frames (120ms) 1 multiframe=51TDMA frames (235.4ms)

1TDMA frame=8 timeslots (120/26=4.615ms)

1 timeslot=156.25 bit duration (4.615/8=0.577ms)(1 bit duration: 0.577/156.25=3.69us)

BCCHCCCHSDCCH

TCHSACCH/TFACCH

1SACCH super-frame=104TDMA frames (480ms)

TS: training sequence


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26-frame multi-frame24TCH/F+FACCH/F+1SACCH/TF+1idle (full-rate TCH)

1SACCH super-frame=4SACCH multi-frame=4*26=104frames(480ms)

Full (Rxlevel/Rxqual)=(26-1idle) *4=100frame measure average Sub (Rxlevel/Rxqual)= 12 frame measure average( under DTX allowed)

(52-59 frame and 4 SACCH frame)

TCH/H+FACCH/H+SACCH/TH (half-rate TCH)

51-frames multi-frameMain BCCH: 5FCCH+5SCH+20BCCH+20CCCH+1idle=51frame

Combined BCCH: (5FCCH+5SCH+4BCCH+12CCCH+16SDCCH/4+8SACCH/C4 )*2=102frame

Main SDCCH: (32SDCCH/8+16SACCH/C8 +3idle)*2=102 frame

Combinations of frame and TA

TB

3

Information

571

Training sequence

261

TB

3

Information

57

147+8.25=156.25bit(0.577ms)

GB

3

1Bit period=0.577ms/156.25=3.68usTA=63bit/max*3.69us/bit=233us for normal cell

Radius/max twice(ms to BTS to ms): 233us*300000km/s=70km

Max cell radius is 70km/2 35km

1TA=1bit=554m

TA=219bit/max in 2 timeslot extended cell,radius/max=120km


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Channels

Broadcast control channel

(BCCH)

Control channelCommon control channel

(CCCH)

Voice channel

(TCH)

FCH SCH BCCH

(system information)

TCH/FAGCH RACH SDCCH FACCH

SACCH

TCH/H

TCH/9.6F

TCH/ 4.8F, H

TCH/ 2.4F, H

PCH

Common channel

(CCH)Dedicated channel

(DCH)

Logical channel


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FCCH

SCHBCCH

PCHAGCH

BCCH

CCCH

CommonChannel

SDCCHSACCH

FACCHTCH/FTCH/H

DCCH

TCH

DedicatedChannel

PCH AGCH

Downlink CCCH

RACH CCCHCommon

Channel

SDCCHSACCHFACCH

TCH/FTCH/H

DCCH

TCH

Dedicated

ChannelRACH

Uplink CCCH

Downlink and uplink channels


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CCCH configuration

Ccch_conf: ccch blocks in a 51 CCCH-multi-frames

When one no-combined case:bs_ag_blks_res: AGCH reserve blocks : 2

bs_pa_mfrms: paging blocks : 2

Paging sub-frame: (9-2)*(bs_pa_mfrms)=14

Ccch config Ccch blocks

one combined 3

one no-combined 9

two no-combined 18

three no-combined 27

four no-combined 36

Pch blocks=Ccch blocks-(bs_ag_blks_res),if ccch_config=1 non_combined, bs_ag_blks_res=2, then PCH=9-2=7.

each CCCH 51-multi-frames will be lasted 235.4msPch blocks/sec= Pch blocks/0.2354ms=29.7 blocks/sec

2 times in each Pch blocks for IMSI paging type

4 times in each Pch blocks for TMSI paging type

So total paging times/max=Pch blocks/sec*(times in each Pch blocks)


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Search for frequency correction burst

Search for synchronization sequence

Read system information

Listen paging message

Send access burst

Wait for signaling channel allocation

Call setup

Assign traffic channel

Conversation

Call release

FCCH

SCH

BCCH

PCH

RACHAGCH

SDCCH

SDCCH

TCH

FACCH

idle mode

off state

dedicated

mode

idle mode

Functions of Channels


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Rxlevel calculation and transmit model

RxLev=EIRP-Path Loss

2, PATH LOSS (predigest formula, need to corrected in project)

Okumura/Hata transmission model for 900M macro network.

Lp=69.55+26.16lg (f)-13.82lg (hb)+(44.9-6.55hb)lg (d)-A (hm)Lp: path loss (db)

f: frequency (Mhz)

hb: BTS antenna height (m)

hm: MS antenna height (m)

d: distance between MS with BTS

Cost-231/Hata transmission model for 1800 macro network

Lp=69.55+26.16lg(f)-13.82lg(hb)+(44.9-6.55hb)lg(d)-A(hm)-KCost-231/Walfish ikegami model for 900/1800 micro networkKeenan-motley model for 900/1800 indoor distribution system.

Planning software for 900/1800 macro system

Path Loss(dB)=k1+k2log(d)+k3Hms+k4log(Hms)+k5log(Heff)+k6log(Heff)log(d)

+k7(Diffraction Loss)+Clutter Loss

1, EIRP: efficient power of BTS.

EIRP=10log[P_Forward(mW)-P_Reflected(mW)]+Tx_Antenna_Gain+Rx_Antenna_Gain-Rx_Feeder_Loss P_Forward: power of forward direction(mW)

P_Reflected: power of reflected direction(mW)

Tx_Antenna_Gain: TX antenna gain of BTS (dbi)

Rx_Antenna_Gain: RX antenna gain dbi)

Rx_Feeder_Loss: loss of feeder cable


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Path Loss(dB)=k1+k2log(d)+k3Hms+k4log(Hms)+k5log(Heff)+k6log(Heff)log(d)

+k7(Diffraction Loss)+Clutter Loss

Note: the values are only reference to, and need to corrected in planning project.K1: loss constant for freq.

Density urban: K1=69.55+26.16lg(F)

Urban : K1=69.55+26.16lg(F)-2[lg(F/28)]2-5.4)

Country : K1=69.55+26.16lg(F)-4.78[lg(F)]2+18.33lg(F)-40.94)

K2: loss constant for distance:

K3,K4: corrected coefficient for mobile antenna height

K5,K6: corrected coefficient for BTS antenna height

K7: corrected constant for diffractionKclutter: corrected coefficient for clutter.

D: distance between mobile and (km)

Hms: height of mobile antenna (m)

Heff: efficient height of BTS antenna (m)

The case parameters in urban and country cities.

Planning software transmission model


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Down-tilt, height and coverage

tg(B-A/2)=H/RB: down-tiltA: vertical beam width

H: antenna height

R1,2,3: coverage range


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Layers and priorities in dual band network

Background:

Traffic increase rapidly

Limited channels in 900 band

Frequency re-use more difficult

Quality decrease

More free channels in 1800 band

Offer loose frequency re-use in 1800band

Parameters set: 900 cells offer coverage service (Layer 3)

1800 cells offer traffic service (Layer 2)

MS stay in Layer 2 more (high cell priority)

Set much CRO in 1800 cells

Set easy access parameters in 1800 cells

Set easy handover to 1800 cells

Set 1800 TRU as overlay in concentric HO

Set 900 TRU as underlay in concentric HO


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RLT (DL) and SACCH multi-frame (UL)

Radio_link_timeout (DL,S(T100) )S+2 when MS decode a SACCH multi-frame correctly, S


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Measure reports (MR) and SACCH frame

MS measure the uplink and downlink during the dedication mode.

MS/BTS measures and report the uplink/downlink information.

The results are prepare for HO, pwr control

A SACCH super-frames is made of 4 SACCH multi-frames.

Total 26 frames in one SACCH multi-frame.

The MS deals with a full MR in a SACCH super-frames, the period is 480ms(4*120ms),

MS retains the previous MR result of 480ms when it is in the next 480ms

MS decode the neighbor cellss BSIC in idle frame

MS retain MR result for 10s if MS find that a BCCH go out from best 6 neighbor cells

to prevent stopping the MR when HO request is sent to this cell.

Contents in MRActual TA of MS

Actual tx-pwr of MS

The BA changes indicator

DTX used indicator

The rx_lev and rx_qual in uplink and downlink

The rxlev,freq, BSIC of the 6 best neighbors


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Frequency reuse and hopping

Common Reuse 4*3 pattern : 4 sites and 3 sector in one frequency groupLack of channel mode: BCCH 4*3, TCH 1*3 or 1*1 hopping

MRP:(multi-reuse pattern) freq. number of Bcch1 Tch2Tch3 Tch4 ...... Tchn

IUO: intelligence underlay and overlay

Hopping: 4*3, 1*3, 1*1(1*3: MA >=2*TRX, ,1*1: MA >=2*TRX(total))

C/I=(useful signal)/(useless signal)

=carrier/interferenceStandard: C/I=9db project: C/I=12db

Standard: C/A=-9db, project: C/A=-6db

C/I must be comply for the formula as below:D=Distance of frequency re-use

R=Radius of cell

N=No. of frequency re-use (E.g. 4*3=12,1*3=3)


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Frequency hopping (4*3, 1*3, 1*1)

4*3 hopping

Same frequency as 4*3(MA)

1*3 hopping

Each cell have a MA in same siteSame MA and MAIO in same

direct cells in different sites

Be sure no neighbor-MAIO in same

cell or in the same direct cells.

Will get more interfering if the

azimuth of sites is not regular

1*1 hoppingEach cell have the same MA in all cells

Different MAIO in each cell in one site

Same MAIO in same direct cells in different sites


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No co-channel frequency carriers in one BTS.

The frequency separation between BCCH and TCH in the same cell should be not less

than 400K.

When frequency hopping is not used, the separation of TCH in the same cell should be

not less than 400K.

In non-1*3 reuse mode, co-channel should be avoided between the immediately neighbor

BTS.

Neighbor BTS should not have co-channels facing each other directly.

Normally, with 1*3 reuse, the number of the hopping frequencies should be not less than

twice of the number of frequency hopping TRX in the same cell.

Pay more attention to co-channel reuse, avoiding the situation that the same BCCH and

BSIC in adjacent area.

Frequency planning principles


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Principle of AMR

AMR (Adaptive Multi Rate) is the set of different speech code rate. BTS and MS select and adjustthe appropriate rate according to RQI, so that to improve the MOS quality of network.

system select and adjust to low AMR when RQI is bad (or interfering is high);

System select and adjust to high AMR when RQI is good (or interfering is low)

AMR-FR set (8):12.2k(GSM EFR)/10.2k/7.95k/7.40k(IS-641)/6.70k/5.90k/5.15k/4.75k

AMR-HR set (5):7.40k(IS-641)/6.70k/5.90k/5.15k/4.75k

Benefits to network:

Offer better speech quality:the speech quality is

better than EFR/HR when system use AMR-FR

and AMR-HR whether the interfering is high or low.

Improvement the re-use rate of frequency:the

performance is better when system use the No. of

frequency re-use=9(3*3) and 12(4*3) than

N=12(4*3) and 18(6*3), It means that the system

can offer higher No. of frequency re-use mode in

the condition of the same speech quality.

Improvement the edge coverage.For C/I, AMR-FR4.75k need 3dB while EFR 8dB to keep the

FER


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Channel assignment of AMR

Channel assignment principle of AMR

adjust AMR supports according to the busyness type, speech version, circuit pool when BSC receive

the assignment command message which sent from MSCBSC.

Prefer to assign AMR channel if system support AMR.

Prefer to assign common channel if system not support AMR

Parameters for AMR: A interface tag: Phase II+

(BSC32)CIC pool:27

Support FR speech version 1~3

Support HR speech version 1~3

(BSC32)Query TC: support FR/HR speech version 3

Support AMR:AMR switch support

active ACS(FR/HR):4 selected rate for AMR-FR, 3 selected rate for AMR-HR

AMR start mode: the original AMR rate

AMR UL/DL coding rate adj.th1: adjust threshold between 0-1, stet: 0.5db



AMR UL/DL coding rate adj.hyst1: adjust hysist between 0-1, stet: 0.5db AMR UL/DL coding rate adj. hyst2: adjust t hysist between 1-2, stet: 0.5db

AMR UL/DL coding rate adj. hyst3: adjust hysist between 2-3, stet: 0.5db

The parameters need to comply for these items:0 < th[i] < th[i+1] < 63; i = 1, 2

0 < th[i] + hyst[i] < th[i+1] + hyst[i+1] < 63; i = 1, 2


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Chapter 1 GSM system1. Work items in an optimization project

2. Review of the GSM system






9. SDCCH congestion






41/154

DT analysis and bad coverage/quality

DT analysis itemsCoverage analysis (over CV, less CV, CV confusion, reflection, antenna connection wrong)

BER analysis and suggestion

Freq.interfering and C/I,C/A analysis HO analysis frequency HO, HO failure, HO drop)Call setup fail analysis

Handover analysis

Drop call analysis and suggestion

Leak of micro cell and suggestion

TA analysis

PWR control analysis

CQT

DT KPIsRxlev(Full&Sub)

Coverage rate

Rxqual(Full&Sub)Call setup success rate

Drop call rate

Handover Success rate

TA

Power control level

Reasons of bad coverageVSWR alarm and loss much in downlink

Down-tilt or azimuth is not in reason

Static power class is too low

Bar of the building and the surrounding

Hardware problem or jump cable problem

Far distance between sites

Wrong neighbor cell relation

Over shooting

Coverage confusion

Wrong Antenna connections

Alone island effect

Incorrect parameters

Reasons of bad quality

C/I,C/A interfering (freq.planning)Bad rx_level coverage

VSWR and reflective freq.interfering (overlap)

Hardware problem

Parameters of HO

TMU and reference clock

RF drop call process

Middle frequency interfering


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Crossed cables and Yuanyang Crossed cables

Wrong crossed cablesPlanning azimuth 0/160/260

DT azimuth 160/0/260

Crossed cables between Cell 16101/16102

Yuanyang crossed cablessame Rxlevel in anywhere along azimuth directionsRxlevel in one direction are better than the other

2 TX/RX are connect to Cell 1091(good signal)

2 RDX are connect to Cell 1093(bad signal)


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Wrong azimuth or Confused coverage

Wrong azimuthPlanning azimuth 85/170/240

DT azimuth 330/220/60

Neighbor relationship and frequency

Confused coverageNeed to check azimuth in cell 3201/3203

Need to confirm in every cablesPending? Reflection?

Neighbor relationship?


44/154

Wrong location and interfering

Wrong Long/Lati

Planning coverageNeighbor relationships

Frequency interfering

Channel interfering

Planning coverage and azimuthBad Frequency plan

Wrong coverage against planning


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Overshooting and low coverage

Overshooting and interfering

12km overshootingAdjacent frequency interfering

Neighbor relationships

Drop call

Low coverage

Down-tilt, antenna heightPWR, VSWR, OOS,

Surrounding


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Spliter and Combiner problems

Spliter problemThere is a Spliter in cell id =GSP3671

Azimuth=40/160

no signal of GSP-1 in direction of 40 degree

No installed Spliter yet

Combiner problemCrossed cables between 3011 and 3012Almost no signal in 3011

Rxlevel loss have 30db via the combiner between

GSM and CDMA


47/154

Jump cables or TRX problem in cabinet

Jump cables problem in cabinetTCH allocation always failure in some TRX

Very less times in TCH seizure successful times

Incoming handover failure

One TRX OOS in cabinetOne of TRX in a cell have low signal suddenly

The other TRXs have no problem

VSWR alarm or OOS


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OOS and no main service cell

Out of service (OOS)

VSWR-2 alarm?LapD or transmission broken?

No power supply?

Locked?

No main service cell

Simulate rxlevelNo cell can offer main service

offer a main service cell

Install a new main service cell or site


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Wrong CGI in MSC

Wrong CGI in MSCMS cant make any calls

All calls are blocked

TCH seizure times for call are 0 times

Support incoming and outgoing handover


50/154

Drop call analysis

Process of RF drop callsRLT+2 and until to the max_RLT if MS decode SACCH frame correctly ,

RLT-1,if MS cant decode SACCH frame ,

RLT is decreased to 0 when MS continue un-decoded SACCH frame, RF drop call occurs.

uplink is as the same as downlink,the counter SACCH multi-frame.Main reason of drop calls

interferingBad rx_lev

hardware problem.

RLT, Sacch-multi-frame not correct.

TRX Pwr class difference in the same cell.

HO drops.

Nei cell relations problem.

Incorrect HO algorithm and parameters

Handover drop callIncorrect PWR control arameter.


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6. OMCR statistics data and the formula in common use

7. Main methods in the performance analysis procedure


9. SDCCH congestion






52/154

BSC level taskBSC measurement performance

Cell level task

Immediate assignmentSDCCH

TCH

Congestion

Drop

Handover

Concentric

Channel capacity and availability

TRX level taskPath balanced

Received Level

Received Quality

Channel allocation

Interfering on idle

Timing Advanced

RQI

Other taskA-interface performance

MTP statistics

GPRS/EGPRS resource

Frequency scan

GSM cell to cell outgoing/incoming handover

Especial abnormal cell tasks (according users need)

Traffic statistics task introduction


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ChannelsCA300J:Channel Requests (Circuit Service)

CA303J:Call Setup Indications (Circuit Service)

CA304:Call Setup Indications Timed Out

RA303G:Success Rate of Call Setup (Immediate Assignment)

K3006:Configured SDCCH

K3004:Traffic Volume on SDCCH

K3000:SDCCH Seizure Requests

K3003:Successful SDCCH Seizures

CM30:Call Drops on SDCCH

K3001:Failed SDCCH Seizures due to Busy SDCCH

K3015:Available TCHs

K3016:Configured TCHs

CR3027:Mean Number of Available Channels (TCHF)

CR3028:Mean Number of Available Channels (TCHH)

K3014:Traffic Volume on TCH (Traffic Channel)K3024:Traffic Volume on TCH (Signaling Channel)

Traffic Volume on TCHH

K3010A:TCH Seizure Requests (Traffic Channel)

K3013A:Successful TCH Seizures (Traffic Channel)

K3011A:Failed TCH Seizures due to Busy TCH (Traffic Channel

Total TCH Call Drops

K3022:Call Drops on TCH (Signaling Channel)

K3012A:Call Drops on TCH in Stable State (Traffic Channel)

K3012B:Call Drops in TCH Handovers (Traffic Channel)

CM330:Call Drops on Radio Interface in Stable State (Traffic Channel)

CM3300:Call Drops on TCH in Stable State (Error Indication)

CM3301:Call Drops on TCH in Stable State (Connection Failure)

CM3302:Call Drops on TCH in Stable State (Release Indication)

CM331:Call Drops on Radio Interface in Handover State (Traffic

Channel)

Cell level statistics items introduction(1)HandoversCH310:Outgoing Internal Inter-Cell Handover Requests

CH311:Outgoing Internal Inter-Cell Handover Commands

CH313:Successful Outgoing Internal Inter-Cell Handover

H312A:Failed Outgoing Internal Inter-Cell Handovers (No Channel Available)

CH312C:Failed Outgoing Internal Inter-Cell Handovers (Timer Expired)

CH330:Outgoing External Inter-Cell Handover Requests

CH331:Outgoing External Inter-Cell Handover Commands

CH333:Successful Outgoing External Inter-Cell Handovers

H332Kc:Failed Outgoing External Inter-Cell Handovers (Handover Request Rejecte

(No Radio Resource Available)

H332Kf:Failed Outgoing External Inter-Cell Handovers (Handover Request Rejected

(Invalid Cell)

CH332C:Failed Outgoing External Inter-Cell Handovers (T8 Expired)

CH342C:Failed Incoming External Inter-Cell Handovers (Timer Expired)

CH300:Internal Intra-Cell Handover RequestsCH301:Internal Intra-Cell Handover Commands

CH303:Successful Internal Intra-Cell Handovers

CH302A:Failed Internal Intra-Cell Handovers (No Channel Available)

CH302C:Failed Internal Intra-Cell Handovers (Timer Expiry)

CH320:Incoming Internal Inter-Cell Handover Requests

CH321:Incoming Internal Inter-Cell Handover Responses

CH323:Successful Incoming Internal Inter-Cell Handovers

H3229A:Failed Incoming Internal Inter-Cell Handovers (No Channel Available) (TCH

H322D:Failed Incoming Internal Inter-Cell Handovers (Reconnection to Old Channel

CH340:Incoming External Inter-Cell Handover Requests

CH341:Incoming External Inter-Cell Handover Responses

CH343:Successful Incoming External Inter-Cell Handovers

H3429A:Failed Incoming External Inter-Cell Handovers (No Channel Available) (TC

H3429Ca:Failed Incoming External Inter-Cell Handovers (Timer Expired) (TCH) (Tr

Channel)


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Cell level statistics items introduction(2)

ConcentricH3001:Internal Intra-Cell Handover Requests (Overlay to Underlay)

CH3031:Successful Internal Intra-Cell Handovers (Overlay to Underlay)

R3225K:Failed Handovers from Overlaid Subcell to Underlaid Subcell due to Busy Channels in Underlaid SubcellH3002:Internal Intra-Cell Handover Requests (Underlay to Overlay)

CH3032:Successful Internal Intra-Cell Handovers (Underlay to Overlay)

R3224K:Failed Handovers from Underlaid Subcell to Overlaid Subcell due to Busy Channels in Overlaid Subcell

R3200:Channel Assignment Requests (Underlaid Subcell Only)

R3202:Channel Assignment Requests (Underlaid Subcell Preferred)

R3202B:TCH Assignment Requests (Underlaid Subcell Preferred)

R3201:Channel Assignment Requests (Overlaid Subcell Only)

R3203:Channel Assignment Requests (Overlaid Subcell Preferred)

R3203B:TCH Assignment Requests (Overlaid Subcell Preferred)

CR3557:Traffic Volume of TCHs (Underlaid Subcell)

CR3558:Traffic Volume of TCHs (Overlaid Subcell)


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Statistics in Trx level

In common useMean Number of SDCCHs in Interference Band 1-5

Mean Number of TCHFs in Interference Band 1-5

Mean Number of TCHHs in Interference Band 1-5

Uplink/Downlink Interference Indication Messages (SDCCH)

Uplink/Downlink Interference Indication Messages (TCH)

Number of MRs (Uplink-and-Downlink Balance Level = 1-11)

Number of MRs (TA = 0-63)

CR440A:Attempted Immediate Assignments

CR440B:Successful Immediate Assignments

R4419A:Attempted Assignments (TCH)

R4419B:Completed Assignments (TCH)

CR443A:Attempted HandoversCR443B:Completed Handovers

S4350D:Radio Link Failures (SDCCH)

S4357D:Radio Link Failures (TCHF)

S4358D:Radio Link Failures (TCHH)

Received qualityquality 0=bit error rate 0.00-0.20% (average 0.14%)

quality 1=bit error rate 0.20-0.40% (average 0.28%)

quality 2=bit error rate 0.40-0.80% (average 0.57%)quality 3=bit error rate 0.80-1.60% (average 1.13%)




quality 7=bit error rate >12.80% (average 18.10%)

Received rxlevelNumber of MRs on uplink/downlink TCHF (receive level

Rank 0-7 receive quality rank 0-7Number of MRs on uplink/downlink TCHH (receive level

Rank 0-7 receive quality rank 0-7


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Formulas in common use-1

TCH drop call rate (excluding HO) (%)=

K3022:Call Drops on TCH (Signaling Channel)+K3012A:Call Drops on TCH in Stable State (Traffic Channel)+K3012B:Call Drops in TCH Handovers (Traffic Channel)K3013A:Successful TCH Seizures (Traffic Channel)

TCH congestion rate (include ho)(%)=

K3011A:Failed TCH Seizures due to Busy TCH (Traffic Channel)+CH302A:Failed Internal Intra-Cell Handovers (No Channel Available)+H3229A:Failed Incoming Internal Inter-Cell Handovers (No Channel Available) (TCH)+

H3429A:Failed Incoming External Inter-Cell Handovers (No Channel Available) (TCH)K3010A:TCH Seizure Requests (Traffic Channel)+CH300:Internal Intra-Cell Handover Requests+CH320:Incoming Internal Inter-Cell Handover Requests+CH340:Incoming External Inter-Cell Handover Requests

CA303J:Call Setup Indications (Circuit Service)CA300J:Channel Requests (Circuit Service)

Imm-assignment success rate(%)=

K3022:Call Drops on TCH (Signaling Channel)+

K3012A:Call Drops on TCH in Stable State (Traffic Channel)+

K3012B:Call Drops in TCH Handovers (Traffic Channel)

K3023:Successful TCH Seizures (Signaling Channel)

K3013A:Successful TCH Seizures (Traffic Channel)

K3013B:Successful TCH Seizures in TCH Handovers (Traffic Channel)

TCH drop call rate (all)(%)=

SDCCH congestion rate(%)= K3001:Failed SDCCH Seizures due to Busy SDCCH

K3000:SDCCH Seizure Requests

SDCCH drop rate (%)= CM30:Call Drops on SDCCHK3003:Successful SDCCH Seizures


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TCH success rate(%)=K3013A:Successful TCH Seizures (Traffic Channel)K3010A:TCH Seizure Requests (Traffic Channel)

Wireless Access success rate(%)= (100%-TCH congesting Rate)X(100%-SDCCH congesting Rate)

Handover outgoing success rate(%)=

CH313:Successful Outgoing Internal Inter-Cell Handover+

CH333:Successful Outgoing External Inter-Cell Handovers+

CH303:Successful Internal Intra-Cell Handovers

CH310:Outgoing Internal Inter-Cell Handover Requests+CH330:Outgoing External Inter-Cell Handover Requests+

CH300:Internal Intra-Cell Handover Requests

Radio outgoing HO success rate(%)=

CH313:Successful Outgoing Internal Inter-Cell Handover+CH333:Successful Outgoing External Inter-Cell Handovers+CH303:Successful Internal Intra-Cell HandoversCH311:Outgoing Internal Inter-Cell Handover Commands+CH331:Outgoing External Inter-Cell Handover Commands+CH300:Internal Intra-Cell Handover Requests

CSSR(%)=RA303G:Success Rate of Call Setup (Immediate Assignment) *(100%-CM30:Call Drops on SDCCH/K3003:Successful SDCCH Seizures)*(K3013A:Successful TCH Seizures (Traffic Channel)K3010A:TCH Seizure Requests (Traffic Channel)

Formulas in common use-2


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9. SDCCH congestion






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Top 20 worst cells from statistics dataCompositor according to the cell level KPIs

Select the top bad 20(or 10)cells in the main items according to times or rate

Analysis the relative bad KPI itemsSolved the bad cells that affect the BSS level performance result

Worst cells

TOP 20 worst cells and DT method

BSC level

Cell level

TRX level

We can resolve the problems from

easy to difficult step by step.

DT methodAnalysis the coverage rationality

Bad coverage area and bettermentAnalysis the abnormal layer 3 message

Interfering analysis

Call setup failure analysis

HO parameters

PWR control parameters


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Signal analysis method:Signaling analysis method requires engineer master every step and statistic counter.

Trace the calls and analysis the signaling information

Analysis problems in the call-process step

Compare the counters in the call process step and find out the max lost count point.

Analysis the every detail call-process step

Find out the problem result

Signalling analysis and compare method

Parameter compare method:Compare the same parameters in different BSC

Compare the different results in different parameter value

Get the best parameter results


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9. SDCCH congestion






62/154

Boundary model of cells and BA table

HO outgoing

boundary,HO_out

Select boundary,

Reselect

HO Incoming

boundary,HO_in

BCCH neighbor listTransmit insystem information message type 2 in BCCH

In use of select and reselect cells

64 cells max

SACCH neighbor listTransmit insystem information message type 5 in SACCH

In use of handover

32 cells max

The two tables can be different,but they are almost the same in common use.


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Process of mobile turn on (selection)

MS have not save the present BCCH info. (initial turn on)Scan all the channel and assess the rx_lev in each ARFCN

MS tune to the max rx-levand judge if it is the BCCH

If it is the BCCH ,then MS try to decode the BCCH info.MS select the cell as flowing

Decode info.correctly,and the cell is among the PLMN

The cell is not BARED;

C1>0

MS saved the present BCCH info. (When turn off)MS scan the saved BCCH when turn on the next time

MS select the cell as flowing

The cell is not bared

C1>0

Else MS check if there is correct cells in the neighbor list.

If there is one,then select the cell as service cell

If there are more,then select the C1/max cell

If there is no,then scan as the case of no BCCH info.


64/154

Cell reselection(C1&C2)

C1= (A - Max. (B, 0))

predigest=(Rxlev Average-rxlev_access_min )

thereinto:A=Rxlev Average - rxlev_access_min

B= ms_txpwr_max_cch - ms Max allowed power

ms Max allowed power(ms pwr class)

ms_txpwr_max_cch(ms pwr class when access)

Reselect principle: (1)C1>0;(2)select C1/max cell

Ms occurs reselect cell in case of any one as below:Downlink failure (DSC=90/bs_pa_mfrms timeout)The cell is bared in BCCH

The C1 of the service cell is < 0 last 5s

Ms hasnt reselect the cells in the past 15s:

To the same LAC, C1 of neis >present cells 5s

To the different LAC,C1 of neis >present cells value (C1+cell_reselect_hysteresis)

Ms not reselection if has reselected in 15s

PT-T=0, H(pt-t)=1

T: time from set 6 best

candidate cell to out of 6 cells

C2=C1+CRO-TO*H(pt-t)+CRH(for PT< 31)

C2=C1-CRO+CRH (for PT= 31)MS assess C2 of nei cell and service cell at least 5s

If C2of best nei cell>C2of service cell for 5s,then Ms select cell

If nei cell and service cell are in different LAC,should add CRH


65/154

Other parameters about reselect(1)

CBA:

No: normal, Yes: barred

PI:

No: C2 not usedYes: C2 used

PHASE2 MS reselection according to C2

PHASE1 MS reselection according to C1

CBQ:

No: normalYes: low

CRO: =2*n dBTO: =10*n dB

PT: =20*(n+1)s

CRH=2*n dB

Cases:PI=0,C2 has no affect (suppose to the same layer)

micro A: C1=35,macro B: C1=45,

so micro A: C1 macro B: C2=45, thus MS prefer to reselect A


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9. SDCCH congestion


11. Call progress introduction in common use

12. Power control algorithm




67/154

SDCCH and Location updateMs will occur location update as follows:

Choose a new LAC cell as the service

T3212 timeout

ATT(IMSI attach and detach)

Roaming location update (inter mobile operators)

Choose reasonable parameter with SD congestion cell

Partition LAC in reason

Choose correct parameter about T3212

Add SDCCH channels

Active SDCCH dynamic configuration

Choose correct C1,CRO,CRH

SDCCH process died (reset BCCH TRX)

MS BTS BSC MSC

Channel_req Channel_Required(2)

Channel_Active(3)

Channel_Active_Ack(4)

IMMEDIATE ASSIGN COMMAND (5)

Establish_IND(Location Updating Req) (6)

CR(Complete_L3)

Location Updating Accepted (10)

TMSI Reallocation Complete (11)

CC

(NOTE 3) Clear_CMD

Clear_CMP

First SABM

SDCCH traffic includes:Call setup (MOC,MTC)

Location update

SMSATT

CDB (cell database broadcast)

SDCCH dynamic configuration parameters

SDCCH dynamic allocation allowed

switch-yes/no

Idle SD thrth.

TCH change to SD(for TCH>4 or TRXs)

Cell SD maximum

=SD configured +8Tch minimum recovery times

minimum time from TCH to SDCCH and back to TCH

Idle TCH thrth N1

When TCH change to SD,it is set a count as ResTIME.

And during the period of SD return to TCH,

if idle SD>N1+8, then count-3->0,SD return to TCH

If idle SD


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9. SDCCH congestion






R f ti


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Reasons of congestion

Reasons of TCH congestionTraffic not balanced between service and neighbors

Traffic not balanced between underlay and overlay in concentric

Hardware problem and some TRX OOS.Traffic is more than the capacity.

Incorrect coverage area

Incorrect C1,C2 parameters

Incorrect HO parameters

Transmission problem

SDCCH congestion but TCH traffic low

Ways to resolve TCH congestionResolve the hardware and transmission problem

Traffic balanced to neighbors or lay with low traffic usage

Adjust azimuth and downtilt so that adjust the coverage and traffic

Adjust handover hysteresis,C1,C2,control the traffic direction

Adjust min DL level on candidate cell in busy cell

Active Half-Rate function

Lower TCH traffic busy threshold%Active direct retry

Layer and priority

-PBGT handover

Allow load handover function

Add more TCH channels or more TRX

Balance the traffic between underlay and overlay


70/154

Abnormal bo ndar ( PBGT and pingpong HO)


71/154

Abnormal boundary (-PBGT and pingpong HO)

2-HO to nei cells1-setup

Rselect

HO_out.

Reselect>RHO_outreselect

C1= (A - Max. (B, 0))

predigest=(Rxlev Average-rxlev_access_min )Thereinto :

A=Rxlev Average - rxlev_access_min

B= ms_txpwr_max_cch - ms Max allowed power(ms pwr class)1, C1(cell A)-C1(cell B)=RXLEV_BCCH-RXLEV_ACCESS_MIN>0

2, PBGT(N)=-RXLEV_BCCH >HO_MARGIN , so C1(cell B)-C1(cell A)HO_MARGIN+RXLEV_ACCESS_MIN HO_out

HO_MARGIN AB= -5, RXLEV_ACCESS_MIN=5(-105dbm)

HO_MARGIN BA=8, RXLEV_ACCESS_MIN=5(-105dbm)

To cell A: RXLEV_ACCESS_MIN+HO_MARGIN(5-5)-5-5


72/154

Direct retry and load HO

Cell B

Cell ADR to the nei cells

RHO_outRselect

Sharing the traffic by DR

(suggest not allowed)

MS2

MS1

RHO_out

MS1 ho to B

RHO_outload ho thrsh

Load HO

MS1

MS1

Load ho bandLoad HO parameters:

Load ho allowed (original cell and direct cell)System flux thrsh. For load ho

Load ho thrsh.

Load req. on candidate cell

Load ho bandwidth

Load ho step period

Load ho step level

Conditions of Direct Retry functionMS setup in cell A,

No more free TCH channels in cell A

Active DR in cell A and B

There is free TCH channels in cell B

TCH d


73/154

TCH drops

Reasons of drop callsInterfering

Bad rx_lev

Bad rx_qual

Coverage confused

Hardware problem and VSWR

HO drops

Neighbor cell relations and data problem.

Antenna physical parameter wrong

Crossed feeder cables

Wrong jump connect cables wrong in cabinet

RLT, Sacch-multi-frame not correct.Incorrect HO algorithm and parameters

TRX PWR class difference in the same cell.

Incorrect PWR control parameter.

Wrong configuration data

Transmission not in stable

TMU version process problem

Radio link not balanced

Drop statistics items for BSC32 (9 items)Unsuccessful TCH seizure (connection failure)

Unsuccessful TCH seizure (error indicator)

Unsuccessful TCH seizure (internal clear)

Unsuccessful TCH seizure (release indicator)Unsuccessful TCH seizure (EMLPP)

Unsuccessful cell internal handover with unsuccessful reversion

Unsuccessful BSC internal handover with unsuccessful reversion

Unsuccessful outgoing BSC handover with unsuccessful reversion

Unsuccessful incoming BSC handover (timeout)

Drop items for BSC6000 (3 summary items)K3022: Call Drops on TCH (Signaling Channel)

K3012A: Call Drops on TCH in Stable State (Traffic Channel)

K3012B: Call Drops in TCH Handovers (Traffic Channel)

K3022: Call Drops on TCH (Signaling Channel)=[Call Drops on Radio Interface in Stable State (Signaling Channel)] +

[Call Drops on Radio Interface in Handover State (Signaling Channel)] +

[Call Drops due to No MRs from MS for a Long Time (Signaling Channel)] +[Call Drops due to Abis Terrestrial Link Failure (Signaling Channel)] +

[Call Drops due to Equipment Failure (Signaling Channel)] +

[Call Drops due to Forced Handover (Signaling Channel)]

K3012A: Call Drops on TCH in Stable State (Traffic Channel)=[Call Drops on Radio Interface in Stable State (TCH)] +

[Call Drops due to No MRs from MS for a Long Time (TCH)] +

[Call Drops due to Abis Terrestrial Link Failure (TCH)] +

[Call Drops due to Equipment Failure (TCH)] +

[Call Drops due to Forced Handover (TCH)]

K3012B: Call Drops in TCH Handovers (Traffic Channel)=[Failed Internal Intra-Cell Handovers (Timer Expired) (TCHF) (Traffic Channel)] +

[Failed Internal Intra-Cell Handovers (Timer Expired) (TCHH) (Traffic Channel)] +

[Failed Outgoing Internal Inter-Cell Handovers (Timer Expired) (TCHF) (Traff ic Chann

[Failed Outgoing Internal Inter-Cell Handovers (Timer Expired) (TCHH) (Traff ic Chann

[Failed Outgoing External Inter-Cell Handovers (T8 Expired) (TCHF) (Traff ic Channel)]

[Failed Outgoing External Inter-Cell Handovers (T8 Expired) (TCHH) (Traffic Channel)]

[Failed Incoming External Inter-Cell Handovers (Timer Expired) (TCH) (Traffic Channe


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9. SDCCH congestion







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Circuit Paging (BSC level)


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3. PAGING REQUEST 2. PAGING COMMAND

MS BTS BSC PCU SGSN MSC/VLR

11'. PAGING12'. PAGING

REQUEST13'. PAGING

REQUEST

A2

4.CHANNEL REQUEST5.CHANNEL REQUIRED

6.CHANNEL ACTIVATION

7. CHANNEL ACKTIVATION

ACKNOWLEDGE

8.IMMEDIATE ASSIGN

CMMAND9. IMMEDIATE

ASSIGNMENT

10. PAGING

RESPONSE

11. EST IND(PAGINGRESPONSE)

C1

A1

B1

1. PAGING

Circuit paging call flowing

A1: received circuit paging messages from MSC

A2: received circuit paging messages from MSC via G-s interface

B1: circuit paging command to BTS

Circuit Paging (BSC level)

BTS BSC MSC/VLR

CCCH LOAD INDICATION

A1

OVERLOADB1

CCCH overload call flowing

A1: circuit paging PCH overloads of Abis interface

B1: circuit paging CCCH overloads of Abis interface

Assignment (BSC level)


78/154

MS BTS BSC

.ASSIGN CMMAND

A1

MSC

ASSIGNMENT REQUEST

SABM

UA

ESTABLISH INDICATION

ASSIGNMENT COMPLETE

(directly retry)HANDOVER REQIRED

MODE (MODIFY)

MODE (MODIFY) ACKNOLEDGE

(NEGATIVE ACKNOWLEDGE,REJECT)

(directly retry)HANDOVER FAILURE(REQUEST ACKNOWLEDGE)

CHANNEL ACKTIVATION

CHANNEL ACKTIVATION ACKNOWLEDGE

(NACK)

ASSIGNMENT COMPLETE

In Immediate Assignment orIntraBSC Handover

ASS FAILURE

H 4

B 2

B 3B 4B 5

C1

C 2

D1E1

F1

F1

F2

F3

F3

F3

G1

G 2G 3

G4

G6

G5

G5

B6

H 2

H 3

H 3

ASS FAILURE

ASS FAILURE

Assignment (BSC level)

Assignment call processA1: assignment requests

C1-C2: unsuccessful assignments(requested terrestrial resource unavailable

E1: unsuccessful assignments(invalid message content)

G1-G6: unsuccessful assignments(no radio resource available)

B2-B6: unsuccessful assignments(equipment failure)

D1: unsuccessful assignments(terrestrial circuit already allocation

F1-F3: unsuccessful assignments(radio interface fail,reversion to the previous channel)H2-H4: unsuccessful assignments(other causes)

Outgoing BSC handover (BSC level)


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MS BSC2BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMAND

MS

HANDOVER ACCESSHANDOVER DETECT

HANDOVER COMPLETEHANDOVER COMPLETE

CLEAR COMMAND

CLEAR COMPLETE

A1

B1

C1

D1 , E1, F1

Outgoing BSC handover (BSC level)

Attempt outgoing BSC handoversA1: attempt outgoing BSC handovers

B1: attempt outgoing BSC handovers (from 900)

C1: attempt outgoing BSC handovers (from 1800)

D1: outgoing BSC handovers

E1: outgoing BSC handovers (900->1800)

F1: outgoing BSC handovers (1800->900)

MS BSC2BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMAND

HANDOVER DETECT

HANDOVER COMPLETE

CLEAR COMPLETE

A1, B1, C1 , D1, E1

CLEAR COMMAND

Successful outgoing BSC handovers

A1: successful outgoing BSC handovers

B1: successful outgoing BSC handovers (from 900 to 900)

C1: successful outgoing BSC handovers (from 1800 to 1800)

D1: successful outgoing BSC handovers (900->1800)

E1: successful outgoing BSC handovers (1800->900)

BTS BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER COMMAND

CLEAR COMMAND

CLEAR COMPLETE

A1

HANDOVER FAILURE

HANDOVER FAILURE

CLEAR COMMAND

CONN FAIL IND

ERROR INDICATION

HANDOVER COMMAND

B1

B2

B3

Unsuccessful outgoing BSC handovers

A1: unsuccessful outgoing BSC handovers with successful reversion

B1-B3: unsuccessful outgoing BSC handovers with unsuccessful reversion

Incoming BSC HO (BSC level)


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Incoming BSC HO (BSC level)

Unsuccessful incoming BSC handovers

A1-A5 : unsuccessful incoming BSC handovers

B1-B2: unsuccessful incoming BSC handovers(equipment failure)

C1-C3: unsuccessful incoming BSC handovers (other causes)

D1 : unsuccessful channel activation in incoming BSC handovers(NACK)

Successful Incoming BSC handovers

A1: successful incoming BSC handovers

B1: successful incoming BSC handovers(900->1800)

C1: successful incoming BSC handovers(1800-900)

D1: successful incoming BSC handovers(900 to 900)

E1: successful incoming BSC handovers 1800to 1800)

F1: attempt incoming BSC handovers

Immediate assignment (cell level)


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MS BTS BSC

CHANNEL REQUEST

CHANNEL REQUIRED

CHANNEL ACTIVATION

CHANNEL ACTIVATION ACKNOWLEDGE

IMMEDIATE ASSIGN CMMAND

SD-ATT-C1TCH-ATT-C1TCH-ATT-BSC1SD-ATT-BSC1TCH-ATT-C 6

TCH-ATT-C 7

TCH-SUCC-C 6TCH-SUCC-C 1

TCH-ATT-C 62TCH-ATT-C 61

SD-SUCC-C 1

EST_IND

SD-SUCC-C4Immediate assignment process

SD-ATT-C1: attempted SDCCH seizures(all)

TCH -ATT-C1: attempted TCH seizures(all)TCH -ATT-C6: attempted TCH seizures for very early assignment

TCH -ATT-C7: attempted TCH seizures for SDCCH overflow

SD-SUCC-C1: successful SDCCH seizures(all)

SD-SUCC-C4: successful SDCCH seizures for immediate assignment

TCH -SUCC-C6: successful TCH seizures for very early assignment

TCH -SUCC-C1: successful TCH seizures(all)

TCH -SUCC-C61: successful TCH allocation for very early assignment

TCH -SUCC-C62: successful TCH allocation for SDCCH overflow

Immediate assignment (cell level)

Assignment (cell level)


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MS BTS BSC

.ASSIGN CMMAND

MSC

ASSIGNMENT REQUEST

SABM

UA


ASSIGNMENT COMPLETE

(directly retry)HANDOVER REQIRED

(directly retry)HANDOVER REQUEST ACK

CHANNEL ACTIVATION

CHANNEL ACTIVATION ACK

TCH-ATT-C 2TCH-ATT-C 8TCH-ATT-C 9TCH-ATT-C 10TCH-ATT-C 5

TCH-ATT-C13

TCH-ATT-C14QUEUEING INDICATION

TCH-ATT-C16

TCH-ATT-BSC 2

TCH-SUCC-C23

TCH-SUCC-C21,22

TCH-SUCC-C51,54,55,56

TCH-SUCC-C52,53,54,55,56TCH-SUCC-C82,83

TCH-SUCC-C81TCH-SUCC-C91TCH-SUCC-C101

TCH-SUCC-C92,93TCH-SUCC-C102,103

TCH-SUCC-C13

TCH -ATT-C2: attempted TCH seizures(all)

TCH -ATT-C5: attempted TCH seizures for callTCH -ATT-C8: attempted TCH seizures for MOC

TCH -ATT-C9: attempted TCH seizures for MTC

TCH -ATT-C10: attempted TCH seizures for call-reestablish

TCH -ATT-C13: attempted TCH seizures for directed retry

TCH -ATT-C14: TCH queue requests

TCH -ATT-C16: TCH preemption

TCH -SUCC-C21--23: successful TCH seizures(all)

TCH -SUCC-C51--53: successful TCH seizures for callTCH -SUCC-C81--83: successful TCH seizures for MOC

TCH -SUCC-C91--93: successful TCH seizures for MTC

TCH -SUCC-C101--103: successful TCH seizures for call-reestablish

TCH -SUCC-C13: successful TCH for directed retry

TCH -SUCC-C54: successful assignments of speech v1 TCH



Assignment (cell level)

TCH call drop (cell level)


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MS BTS BSC

.ASSIGN CMMAND

MSC

ASSIGNMENT REQUEST

SABM

UA


CHANNEL ACTICATION

CHANNEL ACTIVATION ACK

A1

ERROR INDICATION

CONNECTION FAILURE INDICATION

A2

TCH call drop (cell level)

Call drop process

A1: TCH call drop (error indication)

A2: TCH call drop (connection failure)

Internal inter cell HO


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MS BTS' BSC Ori-Cell

HANDOVER ACCESS

UA

Intercell Handover Request

TCH-ATT-C11

BSC Des-Cell BTS''

MRHandover algorithm

HANDOVER COMMAND

Intercell Handover Response

HANDOVER DETECT

CH ACT

CH ACT ACK

HANDOVER COMPLETE

Inter Clear Request

(Handover Success)

TCH-ATT-BSC3SD-ATT-BSC2TCH-ATT-C17TCH-ATT-C3

TCH-SUCC-C17TCH-SUCC-C3

SD-SUCC-C2

SD-ATT-C2

SABMTCH-SUCC-C11

Internal inter cell HO

Internal inter cell handovers

SD-ATT-C2: attempted SDCCH seizures(all)TCH -ATT-C3: attempted TCH seizures(all)

TCH -ATT-C11: attempted TCH seizures for intraBSC incoming cell handover

TCH -ATT-C17: attempted TCH seizures for intracell handover

TCH -SUCC-C17 : successful TCH seizures for intracell handover


TCH -SUCC-C11: successful TCH seizures for intraBSC incoming cell handover

SD-SUCC-C2: successful SDCCH seizures for handover,

successful SDCCH seizures(all)

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1, B1, C1, D1, E1

ASSIGNMENT REQUEST

ASSIGNMENT COMPLETE

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

HANDOVER PERFORMED

A1, B1 , C1, D1, E1, F1

Non_DR incoming inter cell HO in BSC(simulate with SDCCH handoverA1: successful intracell handovers

B1: successful incoming internal intercell handovers

C1: successful incoming internal intercell handovers (from900)

D1: successful incoming internal intercell handovers (from1800)

E1: successful dual-band intercell handovers

F1: successful incoming internal intercell handovers

successful incoming interBSC intercell handovers

DR incoming inter cell HO in BSC(simulate with SDCCH handover)

A1: successful TCH seizures for intraBSC incoming cell handover

B1: successful incoming internal intercell handovers (from900)

C1: successful incoming internal intercell handovers (from1800)

D1: successful dual-band intercell handovers

E1: successful incoming internal intercell handovers

Internal inter cell HO failure


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MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

HANDOVER PERFORMED

CONN FAIL IND

A1 , B1

New Channel

ERROR IND

Old Channel

CHANNEL ACT

CHAN ACT ACK

HANDOVER DETECTIOIN

CHAN ACT NACKA4

CONN FAIL IND

A2, B2

CONN FAIL INDA3 , B3

A5, B4

ERROR INDA6 , B5

ERROR INDA7 , B6

New Channel

incoming internal inter cell HO failure

A1-A7: unsuccessful incoming internal inter cell handoversB1-B6: unsuccessful incoming internal inter cell handovers(other causes)

Internal inter cell HO failure

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

HANDOVER PERFORMED

CONN FAIL IND

New Channel

ERROR IND

Old Channel

CHANNEL ACT

A1 , F2

CONN FAIL INDA2, F3, H1,J1

A4, F4

ERROR INDA5, F5, H2, J2

.HANDOVER FAILURE

A3, B1, C1, D1, E1, F1, G1, I1

CLEAR COMMAND

A6, F6

CLEAR COMMAND

A7, F7Old Channel

Outgoing internal inter cell HO failure

A1-A7: unsuccessful outgoing internal intercell handovers

B1: unsuccessful outgoing internal intercell handovers (channel mode unacceptable)

C1: unsuccessful outgoing internal intercell handovers (TA out of rage)

D1: unsuccessful outgoing internal intercell handovers (freq. not implemented)

E1: unsuccessful outgoing internal intercell handovers (timer expired)

F1-F7: unsuccessful outgoing internal intercell handovers (other causes)G1: unsuccessful internal intercell handovers with successful reversion

H1-H2: unsuccessful internal intercell handovers with unsuccessful reversionI1: unsuccessful outging cell handovers with successful reversion

J1-J2: unsuccessful outging cell handovers with unsuccessful reversion

Outgoing interBSC inter cell HO


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MS BSC2BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMAND

MS

HANDOVER ACCESSHANDOVER DETECT

HANDOVER COMPLETEHANDOVER COMPLETE

CLEAR COMMAND

CLEAR COMPLETE

A1

B1 , C1, D1, E1, F1

HANDOVER REQUIRED

HANDOVER REQUEST

HANDOVER REQ ACK

Outgoing interBSC inter cell HO

outgoing Inter bss inter cell HO attemptedA1: attempt outgoing interBSC intercell handovers

B1: inter BSC outgoing cell handovers

C1: outgoing interBSC inter cell handovers(to900cell)

D1: outgoing interBSC inter cell handovers(to900cell)

E1: successful dual-band intercell handovers

F1: attempted outgoing intercell handovers(12 causes)

MS BSC2BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER REQUEST

HANDOVER REQ ACK

HANDOVER COMMAND

HANDOVER COMMAND

HANDOVER DETECT

HANDOVER COMPLETE

CLEAR COMPLETE

A1, B1, C1, D1, E1

CLEAR COMMAND

outgoing Inter bss inter cell HO successfulA1: successful outgoing interBSC intercell handovers

B1: successful outgoing interBSC inter cell handovers(to900cell)

C1: successful outgoing interBSC inter cell handovers(to900cell)

D1: successful dual-band intercell handovers

E1: successful outgoing intercell handovers(12 causes)

BTS BSC1 MSC/VLR

HANDOVER REQUIRED

HANDOVER COMMAND

CLEAR COMMAND

CLEAR COMPLETE

A1, C1

HANDOVER FAILURE

HANDOVER FAILURE

CLEAR COMMAND

CONN FAIL IND

ERROR INDICATION

HANDOVER COMMAND

B1 , D1

B2 , D2

B3 , D3

inter bss outgling handover failure

A1: unsuccessful outgoing BSC handovers with successful reversionB1-B3: unsuccessful outgoing BSC handovers with successful reversion

C1: unsuccessful outgoing cell handovers with successful reversion

D1-D3: unsuccessful outgoing cell handovers with unsuccessful reversion

Incoming interBSS inter cell HO


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MS Other BSC

HANDOVER ACCESS

UA

HANDOVER REQUIRED

TCH-ATT-C12

HUAWEI BSC HUAWEI BTS

HANDOVER COMMAND

HANDOVER REQUEST ACK

HANDOVER DETECT

CH ACT

CH ACT ACK

HANDOVER COMPLETE

TCH-ATT-BSC4SD-ATT-BSC3

MSC

TCH-ATT-C15 QUEUEING INDICATION

TCH-ATT-C4

TCH-SUCC-C4TCH-SUCC-C12

SD-SUCC-C3

SD-ATT-C3

SABM

HANDOVER REQUEST

Incoming interbsc inter cell HO

SD-ATT-C3: attempted SDCCH seizures(all)

TCH -ATT-C4: attempted TCH seizures(all)

TCH -ATT-C12: attempted TCH seizures for inter bsc incoming handovers


TCH -SUCC-C12: successful TCH seizures for inter bsc incoming handover

SD -SUCC-C3: successful SDCCH seizures for handover

successful SDCCH seizures for(all)

Incoming interBSS inter cell HOMS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER DETECTION

A1, B1, C1

CHANNEL ACT

CHAN ACT ACK

HANDOVER COMPLETE

HANDOVER REQ ACK

HANDOVER REQUESTT

incoming inter bss HO Success

A1: successful incoming inter bsc inter cell handover

B1: successful dual-band intercell handovers

C1: successful incoming intercell handovers

MS BTS New BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

HANDOVER COMPLETE

Old Channel

CONN FAIL IND

HANDOVER DETECTION

A1

New Channel

HANDOVER REQUEST

Old BSC

HANDOVER REQUIRED

CHAN ACT

CHAN ACT ACK

CHAN ACT NACK

New Channel

A2

CLEAR COMMAND

CLEAR COMMAND

CLEAR COMMAND

A3

A4

A5

A3

HANDOVER REQ ACKHANDOVER COMMAND

inter bss incoming handover failure

A1-A5 : inter bsc incoming cell handovers

Intracell HO


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MS BTS BSC MSC/VLR

HANDOVER COMPLETE

HANDOVER COMMAND

A1

(Intracell handover)

HANDOVER PERFORMED

Intracell ho success

A1: successful intracell handovers

MS BTS BSC MSC/VLR

HANDOVER COMPLETE

.HANDOVER COMMAND

A2

(Intracell handover)

HANDOVER PERFORMED

CONN FAIL IND

Old Channel

CONN FAIL IND

HANDOVER FAILURE

A3

A1

Old Channel

New Channel

A5

CLEAR COMMAND

CLEAR COMMAND

A4

ERROR INDA6

ERROR IND

A7

Intracell ho failure

A1-A7: unsuccessful intracell handovers

Intracell HO


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9. SDCCH congestion






MR pre-processing and voting


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MR pre-processing Each MR has a serial number. the network will fill up MR according to interpolation algorithm. When

the serial numbers are discontinuous (some MRs missing).

The simple interpolation algorithm is linearity interpolation according the previous and the later MRs

when missing MRs occur.

Calculate average results of several consecutive MRs to obtain current information, reduce the

influence of some abnormal MR for judgment of PWC or HO.

The relation parameters: allowed MR numbers lost, filter length

p p g g

MR MR MRMR MR MR

Consecutive MR flow

Filter length

MR MRMR MR

N

Consecutive MR flow

Interpolation m missing MR

N+1 N+m+1 N+m+2

MR

MR voting (N/P) for GSM0508 protocolN(N1-N8): MR numbers used to voting process in PC and HO

P(P1-P8): MR numbers exceeded voting threshold in PC and HO,

The process will be performed when the numbers of P over the threshold in N.

Parameters relation to PWR control: P1-4/N1-4

Parameters relation to HO: P5-8/N5-8

P/N5-8 >P/N1-4

When the rxqual or rxlev is not good ,the system try to adjust PWC before HO

Power Control Overview


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Process of power control commands

It takes 3 measurement report periods(3*480ms) from command

sending to execution.

SA SA1A SAA1A1 SA2A2A2 SA3A3A3

BTS sends the command

for power control and TA

in SACCH header.

MS obtains

SACCH block

MS begins to send the

measurement report of the

last multi-frame.

In the 26 multi-

frames, frame 12

sends SACCH.

BTS receives the

measurement report

SACCCH report period:

26X4=104 frames (480ms)

MS adopts the new

power level and TA

MS begins to set up a new SACCH

header to report the new TA andpower control message.

PWC algorithm overview


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Huawei PC algorithm: HW I and HW II power control

Measurement reportpre-processing

Power control algorithm

selection

Yes

HW I power control

algorithm

HW II power control

algorithm

GSM0508 power control

Algorithm (ordinary)

g

Parameters of ordinary PWR control window


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y

MS: uplinkUL PC allowed

Rx-lev thrsh.for UL increase=20(-90)

N1/P1

Rx_lev thrsh.for UL decrease=40(-70)

N2/P2

Rx_qual thrsh.for UL increase=5

N3/P3

Rx_qual thrsh.for UL decrease=1

N4/P4

BTS: downlinkDL PC allowed

Rx-lev thrsh.for DL increase=20(-90)

Rx_lev thrsh.for DL decrease=40(-70)Rx_qual thrsh.for DL increase=5

Rx_qual thrsh.for DL decrease=1

PC period

MS(uplink) are independence correspondingly and the PWC is rapidGoal: adjust MS tx pwr to let BTS receive stable signal, reduce the uplink

interference, reduce power of MS.

BTS(downlink) is relations all the MS in this cell and the PWC is slow.Goal: adjust BTS tx pwr to let MS receive stable signal, reduce the downlink

interference, reduce power of BTS

So it mainly means UL PWC in the Power Control process on this hand.

Ordinary PWC window


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-110 -110

MS(UL):Rx_lev thrsh.for UL decrease=40(-70)

Rx-lev thrsh.for UL increase=20(-90)

BTS(DL):Rx_lev thrsh.for DL decrease=40(-70)

Rx_lev thrsh.for DL increase=20(-80)

-80

-100

-70

-90

-80

-100

-70

-90

Rx_qual thrsh.for UL decrease=1

Rx_qual thrsh.for DL decrease=1

Rx_qual thrsh.for UL increase=5

Rx_qual thrsh.for DL increase=5

0

BER

2

4

6

7

0.14%(0-0.2%)

0.57%(0.4-0.8%)

2.26%(1.6-3.2%)

9.05%(6.4-12.8%)

18.10%(>12.8%)

grade

1 0.28%(0.2-0.4%)

3 1.13%(0.8-1.6%)

5 4.53%(3.2-6.4%)

y

Huawei I PWC algorithm (average PWC)


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The adjust value

=(DL/ul rx_lev expectedcurrent dl/ul rx_lev) * DL /ul rx_lev compensation

+[current dl/ul rx_qualDL/ul rx_qual expected]*10* DL/ul rx_qual compensation

The adjust value UL edge ho

UL RX_LEV Compensation

UL Qual. Expected

UL Qual. Compensation

MAX PWC Step

PWC Interval

MS PWC Period

Filter Length for Initial RX_LEVFilter Length for Stable RX_LEV

Filter Length for Qual.

Power Increment after HO Fail.

BTS: downlinkDL RX_LEV Expected

DL RX_LEV Compensation

DL Qual. ExpectedDL Qual. Compensation

MAX PWC Step

BTS PWC Period

Filter Length for DL RX_LEV

Filter Length for DL Qual.

Huawei II PWC algorithm (self-adapt PWC)


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Lack of huawei I PWC algorithm:Average PWC algorithm has a delay when system analysis the MRs ,so system cant adjust rapidly.

System only analysis the past MR results and cant expected the PC direct well.

Exit the oscillate cases when the PWC process is near to the expected value.

Huawei II PWC algorithm:Adjust the LEV PWC direct in vary LEV value by comparing expected and current value.

Adjust the QUAL PWC direct in fixed QUAL value by comparing expected and current value

Assess the final PWC direct and PWC value by calculating LEV PWC and QUAL PWC synthetically.

When the PWC direction is the same ,the PWC value take the more value

When the PWC direction is opposition , the PWC is preferred to the value of PWC by LEV.

PC by lev PC by qual PC by lev and qual

AdjStep_Lev AdjStep_Qul max(AdjStep_Lev,AdjStep_Qul)

AdjStep_Lev AdjStep_Qul No action

AdjStep_Lev No action AdjStep_Lev

AdjStep_Lev AdjStep_Qul AdjStep_LevAdjStep_Lev AdjStep_Qul max(AdjStep_Lev,AdjStep_Qul)

AdjStep_Lev No action AdjStep_Lev

No action AdjStep_Qul AdjStep_Qul

No action AdjStep_Qul AdjStep_Qul

No action No action No action

Huawei II PWC algorithm (PWC direct and value)


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Adj. step_lev in UL: UL rx_levUL rx_lev upper thrsh., MS decrease pwr.

adj. step_lev=ul rx_lev - (UL rx_lev lower thrsh. +UL rx_lev upper thrsh.)/2

UL rx_lev lower thrsh < UL rx_lev


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Summary and classification of HO


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Summary of HOHO can decrease drop calls and relief congestion when MS is moving

Ms report best 6 neighbor cells in MR and BSS votes whether HO occurs and direct nei cell

System sends handover command message ,and start HO process.

inside shows AFRCN,TS,BCCH,BSIC,PC level,TSC,HO cause, sync/Async about the direct cell.

MS send handover complete in the direct cell if MS handovers to direct cell successfully.

When MS HO to direct cell unsuccessfully,

if ms reverse to the source cell successfully,ms sent HO failure message to system

else if reverse unsuccessfully when the timer is timeout, HO call drop occurs in this case.

The message assignment command/complete is used in intra-cell HOs.

Classification of HO Emergency HO

Timing Advance (TA) Emergency HO

Bad quality (BQ) Emergency HO

Rx_Level_Drop Emergency HO

Interference Emergency HO

Load HO

Normal HO Edge HO

Layer HO

Power Budget (PBGT) HO

Speed-sensitive HO (Fast moving MS HO)

Concentric Cell HO

Priority level of HO


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M.R.

preprocessing

Penaltyprocessing

Basic ranking

Secondaryranking

HO voting

emergency HO

TA

bad quality(BQ)rapid lev decrease

interfering

Load Sharing HO

normal HOEdge

layer

PBGT

Processingprogram

OMC forced HO

Directed retry

Overlaid/

underlaid HO

Fast moving MSHO

HO penalty and ranking rules


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HO penalty process (second step of HO algorithm process ) Penalty on the target cell when a HO fails.

avoid to the ms select this cell again in the next HO voting process.

Penalty on the original serving cell when an emergency HO ( base on BQ and TA ) is performed.avoid MS to be handed back to the BQ&TA cell again within penalty time.

Penalty on other high priority layer cells after a fast moving HO is performed.

avoid MS to be handed back to the high priority layer again within certain time(layer priority grade is 4).

A new HO attempt is prohibited within the penalty time after an overlaid/underlaid HO fails.

Ranking rules

M rule for ranking neighbor cellsit can be put into the candidate cell list only if the cells comply for following conditions.

To service cell: Rx_lev(s)rxlev access min(s)-MAX(0,Pa(s)) > 0

Pa(0) =ms_txpwr_max_ccch(s)ms_max_allowed_pwr(s)

To nei cell: Rx_lev(n)rxlev access min(n)-max(0,Pa(n))min_access_level_offset(n)>0

K rule for ranking neighbor cells

Sort the result cells in descending order by rxlev according to M rule cells.

16bits rule for ranking cells:Both the serving cell and the neighbor cells have their own 16bits value.

The smaller the value is, the higher the priority and position the cell is in the cell list.

Basic/Secondary Ranking(16 bit rule)


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HUAWEI - statistics data analysis and optimization V 4.0.ppt