GSMGPRSEDGE Planning Overview.pdf

7/27/2019 GSMGPRSEDGE Planning Overview.pdf

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Confidential Do not share without prior permission

GSM/GPRS/EDGE Planning

Overview


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1.Planning Process Overview

2.Introduction to GSM network

3.Mobile radio link

4.Network & Frequency planning

5.Network Modeling

Course Contents

Slide 2 of 2Confidential Do not share without prior permission


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1.Planning Process Overview

Traffic and Coverage AnalysisNominal Cell Plan

Surveys

Detailed Design

Implementation

Tuning

System Growth

Confidential Do not share without prior permission Slide 3 of 2


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2.Introduction to GSM network

Another MSC

HLR/AUC/LR

SMC

PSTN

ISDN

OMC

MS

Um interface

MS

Um

Um

A-bis

interface

BSC

A interface

MAP interface

BTS

MSC



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Communication management (CM)

Radio resources management (RR)

Mobility and security management

(MM)

Integrated management

TCH0 TCH1 TCH2SACCHTCH23 IDL

MultiframePhysical link layer (L1)

Data link layer (L2)

Network application layer (L3)

Hierarchical Structure of Um Interface

RACH BCCH AGCH/PCH SDCCH SACCH TCH FACCH



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GSM Bandwidth

GSM 900 :

Channel spacing 200kHz

GSM 1800 :

Channel spacing 200kHz

1710 1785 1805 1880

Duplex Spacing : 95 MHz

890 915 935 960

Duplex Spacing : 45 MHz



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Difference Between GSM900 and GSM1800

GSM900 and GSM1800 are similar

GSM 900 GSM 1800

Frequency band 890...960 MHz 1710...1880 MHz

Number of channels 124 374

Channel spacing 200 kHz 200 kHz

Access technique TDMA TDMA

Mobile power 0.8 / 2 / 5 W 0.25 / 1 W



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Logical Channels

GSM900/GSM1800 logic channel architecture

Broadcast Control

Channel (BCCH)Control ChannelsCommon Control

Channel (CCCH)

Traffic Channels

(TCH)

FCH SCH BCCH

(Sys Info)

TCH/FAGCH RACH SDCCH FACCH

SACCH

TCH/H

TCH/9.6F

TCH/ 4.8F, H

TCH/ 2.4F, H

PCH

Common Channels

(CCH)

Dedicated Channels

(DCH)

Logical Channels



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Downlink Channels

FCCH

SCH

BCCH

PCH

AGCH

BCCH

CCCH

Common

Channels

SDCCH

SACCH

FACCH

TCH/FTCH/H

DCCH

TCH

Dedicated

Channels



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Uplink Channels

RACH CCCHCommon

Channels

SDCCH

SACCH

FACCH

TCH/F

TCH/H

DCCH

TCH

Dedicated

Channels



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Use of Logical Channels

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

RACH

AGCH

SDCCH

SDCCH

TCHFACCH

idle mode

off state

dedicated

mode

idle mode



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Logical Channels Mapping

Logical channels are mapped to physical channels

Signaling : sequences of 51 frames

Traffic : sequences of 26 frames

For combined BCCH CCCH blocks can be either PCH or AGCH

Some blocks may be configured as SDCCH

R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R

F S B B B B C C C C S C C C C C C C CF S C C C C C C C CF S C C C C C C C CF S C C C C C C C CF -

51 TDMA frames ~ 235,4 msecBCCH + CCCH (uplink)

BCCH + CCCH (downlink)



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Diversity

Time diversity

Coding, interleaving

Frequency diversity

Frequency hopping

Space diversity

Multiple antennasPolarization diversity

Dual-polarized antennas

Multi-path diversity

Equalizer

t

f



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Benefit From Diversity

Diversity gain depends on environment

Antenna diversity

3dB gain

More path loss acceptable in link budget

Higher coverage range

R

R(div) ~ 1,3 R A 1.7 A

70% more coverage per cell

Needs, less cells in total

The above case can be satisfied

only under ideal condition. That

is the environment is infinitely

large and flat



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Interference

Signal quality =

sum of all expected signals carrier (C )

sum of all unexpected signal interference (I)=

Notes: GSM specification : C / I >= 9 dB (Co-Channel)

expected signal

atmospheric

noise

other signals



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Effects of Interference

Affect signal quality

Cause bit error

Repairable errors : channel coding, error correction

Irreducible errors : phase distortions

Interference situation is

Non- reciprocal : uplink downlink

Unsymmetrical : different situation at MS and BTS

C/I

Co-Channel C/I : 9dB

Adjacent Channel C/I : -12dB



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Signal Quality in GSM

RX Quality

RXQUAL class : 0 ... 7

RXQUAL Mean BER BER range

class (%) from... to

0 0.14 < 0.2%

1 0.28 0.2 ... 0.4 %

2 0.57 0.4 ... 0.8 %

3 1.13 0.8 ... 1.6 %

4 2.26 1.6 ... 3.2 %

5 4.53 3.2 ... 6.4 %6 9.05 6.4 ... 12.8 %

7 18.1 > 12.8 %

usable signal

unusable

signal

good

acceptable



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Interference sources

Multi-path (long echoes)

Frequency reuse

External interference

Note : Interference has the same effect as poor coverage.

Reduce the interference

as possible.



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Methods for reducing Interference

Frequency planning

Suitable site location

Antenna azimuth, downtilt and height

goodlocation

badlocation



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Frequency hopping

A diversity technique, frequency diversity include:

Less fading loss

De-coding gain

Interference averaging

Power control based on quality

Evaluate signal level and quality

DTX

Silent transmission in speech pauses



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Adaptive antennaAccording to subscriber distribution, concentrate signal energy to certain direction.

Adaptive channel allocation

Always assign the best available channel during call setup.



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Frequency Hopping

Diversity techniqueFrequency diversity can reduce fast fading effects

Useful for static or slow-moving mobiles

Cyclic base-band hopping

TRX hops cyclic between its allocated frequencies

Synthesizer hopping

Either cyclic or random hopping

Needs wideband combiner

Can use any frequency included in the MA



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Power Control

Save battery life-time

Minimize interference

GSM : 15 steps and 2 dB for each

Use power control in both uplink and downlink

triggered by level or quality

time

signal

level target level

e.g. -85 dm

Power control isnt allowed

on BCCH



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DTX

DTX (Discontinuous transmission)Switch transmitter off in speech pauses and silence periods, both sides transmit

only silence updates (SID frames) comfort noise generated by transcoder.

VAD: voice activity detection

Transcoder is informed the use of DTX/ VAD

Battery saving and

interference reducing



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Traffic Analysis-Part ofErlangs B-table

n .007 .008 .009 .01 .02 .03 .05 .1 .2 .4 n

1 .00705 .00806 .00908 .01010 .02041 .03093 .05263 .11111 .25000 .66667 1

2 .12600 .13532 .14416 .15259 .22347 .28155 .38132 .59543 1.0000 2.0000 2

3 .39664 .41757 .43711 .45549 .60221 .71513 .89940 1.2708 1.9299 3.4798 3

4 .77729 .81029 .84085 .86942 1.0923 1.2589 1.5246 2.0454 2.9452 5.0210 4

5 1.2362 1.2810 1.3223 1.3608 1.6571 1.8752 2.2185 2.8811 4.0104 6.5955 5

6 1.7531 1.8093 1.8610 1.9090 2.2759 2.5431 2.9603 3.7584 5.1086 8.1907 6

7 2.3149 2.3820 2.4437 2.5009 2.9354 3.2497 3.7378 4.6662 6.2302 9.7998 7

8 2.9125 2.9902 3.0615 3.1276 3.6271 3.9865 4.5430 5.5971 7.3692 11.419 8

9 3.5395 3.6274 3.7080 3.7825 4.3447 4.7479 5.3702 6.5464 8.5217 13.045 9

10 4.1911 4.2889 4.3784 4.4612 5.0840 5.5294 6.2157 7.5106 9.6850 14.677 10

11 4.8637 4.9709 5.0691 5.1599 5.8415 6.3280 7.0764 8.4871 10.857 16.314 11

12 5.5543 5.6708 5.7774 5.8760 6.6147 7.1410 7.9501 9.4740 12.036 17.954 12

13 6.2607 6.3863 6.5011 6.6072 7.4015 7.9667 8.8349 10.470 13.222 19.598 13

14 6.9811 7.1154 7.2382 7.3517 8.2003 8.8035 9.7295 11.473 14.413 21.243 14

15 7.7139 7.8568 7.9874 8.1080 9.0096 9.6500 10.633 12.484 15.608 22.891 15

16 8.4579 8.6092 8.7474 8.8750 9.8284 10.505 11.544 13.500 16.807 24.541 16

17 9.2119 9.3714 9.6171 9.6516 10.656 11.368 12.461 14.522 18.010 26.192 17

18 9.9751 10.143 10.296 10.437 11.491 12.238 13.385 15.548 19.216 27.844 18

19 10.747 10.922 11.082 11.230 12.333 13.115 14.315 16.579 20.424 29.498 19

20 11.526 11.709 11.876 12.031 13.182 13.997 15.249 17.613 21.635 31.152 20

21 12.312 12.503 12.677 12.838 14.036 14.885 16.189 18.651 22.848 32.808 21

22 13.105 13.303 13.484 13.651 14.896 15.778 17.132 19.692 24.064 34.464 22

23 13.904 14.110 14.297 14.470 15.761 16.675 18.080 20.737 25.281 36.121 23

24 14.709 14.922 15.116 15.295 16.631 17.577 19.031 21.784 26.499 37.779 24

25 15.519 15.739 15.939 16.125 17.505 18.483 19.985 22.833 27.720 39.437 25

26 16.334 16.561 16.768 16.959 18.383 19.392 20.943 23.885 28.941 41.096 26

27 17.153 17.387 17.601 17.797 19.265 20.305 21.904 24.939 30.164 42.755 27

28 17.977 18.218 18.438 18.640 20.150 21.221 22.867 25.995 31.388 44.414 28

29 18.805 19.053 19.279 19.487 21.039 22.140 23.833 27.053 32.614 46.074 29

30 19.637 19.891 20.123 20.337 21.932 23.062 24.802 28.113 33.840 47.735 30

31 20.473 20.734 20.972 21.191 22.827 23.987 25.773 29.174 35.067 49.395 31

32 21.312 21.580 21.823 22.048 23.725 24.914 26.746 30.237 36.295 51.056 32



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A call goes through two different devices

(1-GoS1)A

GoS2(1-GoS1)A

(1-GoS1)A (1-GoS2)(1-GoS1)A

GoS1(A+A)+GoS2(1-GoS1)A

GoS1(A+A)

A

A

SDCCH TCH

where GoS1 is the grade of service on the SDCCH and GoS2 is

the grade of service on the TCH. A is the traffic on the SDCCH for normal call

and andA is the traffic that accounts for the rest of the procedures

performed on the SDCCH. The optimum configuration is achieved by

selectinga configuration with as many TCHs as possible, without letting

the GoS1 exceed 1/4 of GoS2Slide 26 of 2Confidential Do not share without prior permission


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Part ofErlangs B-table for 43 channels giving the

offered traffic (E) as a function of the GoS (%)

n .007 .008 .009 .01 .02 .03 .05 .1 .2 .4 n

43 30.734 31.069 31.374 31.656 33.758 35.253 37.565 42.011 49.851 69.342 43

With 43 channels (as in the previous single cell example), the

channel utilization is 33.083/ 43 = 77%, that is, each channel is

used approximately 77% of the time



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What happens when a certain amount of traffic is

distributed over several cells?

Cell Traffic (%) Traffic (E) No. ofchannels

Channelutilization (%)

A 40 13.20 21 62

B 25 8.25 15 54

C 15 4.95 10 49

D 10 3.30 8 40

E 10 3.30 8 40 100 33.00 62

However, by splitting this cell into smaller cells, more traffic channels

are required, hence, the channel utilization decreases.



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3.Mobile radio link

Why we need a link budget?

Which will decide the coverage range?

The coverage range is limited by the weaker one.

Two-way communication needed

link usually limited by mobile transmitting power

Desired result: downlink = uplink

Link budget shouldbe balanced



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Link Budget


Tx

TxReceiver

Divider

Rx

Feeder

Feeder

Feeder

Rx

Combiner

LCBTS

Feeder

LFBTS

LFBTS

PoutMS PinMS

LFMS

GAMS

GABTS

GABTS

GDBTS

Lp

Lp

PinBTSwithout TMA

PinBTSwithTMA

Cabinet

PoutBTS


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Signal Level or Path Loss Calculation


Downlink

Uplink

System Balance

Balancing the system for GSM 900 class 4 mobile stations, that is, PoutMS=2W or 33 dBm, using GdBTS=3.5 dB, and using cell planning values for the

sensitivities as MSsens=-104 dBm and BTSsens=-110 dBm, an output power of

the BTS of 42.5 dBm is obtained


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Log Normal Fading


75% 85% 90% 95% 98%

LNFmarg(o)

for Dense urbanenvironment

-3.1 dB 0.7 dB 3.2 dB 6.8 dB 10.7 dB

LNFmarg(o)

for Urban

environment

-3.4 dB -0.2 dB 1.8 dB 4.9 dB 8.1 dB

LNFmarg(o)

for Suburban &

rural environment

-3.7 dB -1.2 dB 0.5 dB 3.0 dB 5.5 dB


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Rayleigh fading and Interference Margin


Rayleigh fading margin (RFmarg):Rayleigh fading is due to multi path

propagation and occurs especially in urban environments where there is high

probability of blocked line-of-sight between transmitter and receiver.

Typical RF Margin = 3dB

Interference margin (IFmarg):The plain receiver sensitivity depends on the

required carrier to noise ratio (C/N). When frequencies are reused, the

received carrier power must be large enough to combat both noise and

interference, that means C/(N+I) must exceed the receiver threshold. In order

to get an accurate coverage prediction in a busy system, an interferencemargin (IFmarg) is defined.

Typical Interference Margin = 2dB

Body Lo ss: 5dB(900)/3dB (1800)


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Propagation Model

Okumura- HataEmpirical model

Measure and estimate additional attenuations

Applied for larger distance estimation (range: 5 .. 20km)

Not suitable for small distance ( < 1km)



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Hata Model

Model used for 900 MHz

L A B f h a h

h d L

b m

b morpho

log . log ( )

( . . log ) log

1382

44 9 6 55

withf frequency in MHz

h BS antenna height [m]

a(h) function of MS antenna height

d distance between BS and MS [km] and

A= 69.55, B = 26.16 (for 150 .. 1000 MHz)

A= 46.3 , B = 33.9 (for 1000 ..2000MHz)

additional attenuation due

to land usage classes



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Land Usage Types

Urban small cells, 40..50 dB/Dec attenuation

Forest heavy absorption; 30..40 dB/Dec; differs with

season (foliage loss)

Open, farmland easy, smooth propagation conditions

Water propagates very easily ==> dangerous !

Mountain surface strong reflection, long echoes

Glaciers very strong reflection; extreme delay , strong

interferences over long distance

Hilltops can be used as barriers between cells, do not

use as antenna or site location



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Indoor Coverage -Building Penetration Loss

Signal level in building is estimated by using a building penetration lossmargin

Big differences between rooms with window and without window(10~15 dB)

rear side :

-18 ...-30 dB

Pref= 0 dB

Pindoor= -3 ...-15 dB

Pindoor= -7 ...-18 dB

-15 ...-25 dB no coverage

signal level increases with floor

number :~1.5 dB/floor (for 1st

..10th floor)



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Building Penetration Loss

Signal loss for penetration varies between different building materials, e.g.:

mean value

reinforced concrete wall, windows 17 dB

concrete wall, no windows 30 dB

concrete wall within building 10 dB

brick wall 9 dBarmed glass 8 dB

wood or plaster wall 6 dB

window glass 2 dB

Total building loss = median values +superimpose standard deviations +

(lognormal) margin for higher probabilities



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4.Network & Frequency planning



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4.Network Topology

Umbrella cell

Macro cellMicro cell

Pico cell



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Macro Cell Network

Cost performance solutionSuitable for covering large area

Large cell range

High antenna position

Cell ranges 2 ..20km

Used with low traffic volume

Typically rural area

Road coverage

Normally Use omnidirectional antenna

Exception: Use beamed antenna for road coverage



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Micro Cell Network

Capacity oriented networkSuitable for high traffic area

Mostly used with beamed cell

Cost performance solution

Usage of available sites equipment

Typical application

Medium town

Suburb

Typical coverage range: 0.5 .. 2km

0,5 .. 2km



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Layered Network

High layer station

Middle layer stationMiddle layer station

Indoors stationIndoor station

Indoors station

Low layer stationLow layer station

Low layer stationLow layer station

Indoors station



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Bad Site Location

Avoid hill-top location for siteUncontrollable interference

Cross coverage

Bad handover behavior

wanted cell

boundary

uncontrolled, strong

interferences

cross coverage areas:



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Good Site Location

Prefer site off the hill-topUse hill to separate cell

Contiguous coverage area

Need only low antenna height if site are slightly elevated above valley bottom

wanted cell

boundary



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Frequency Planning

Why we reuse the frequency?8 MHz = 40 channels * 8 timeslots = 320 users

==> max. 320 simultaneous calls!!!

Limited bandwidth

Interference are unavoidable

Minimize total interference in network

Use calculated propagation prediction for frequency allocation



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Frequency Planning

Frequency planning always consider the following caseActual situation is different.

Power control, actual traffic and distribution of subscribers.

Average frequency reuse rate is a criteria for good allocation scheme:

practical

limit

safe, butuneconomical

physical

limit

0 10 20



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Frequency Reuse

Reuse frequency as often as possibleIncrease network capacity

But maybe cause some interference

Consideration for frequency reuse

Interference matrix calculation

Propagation model tuning

Minimize total interference in network

R

D

f2

f3

f4f5

f6

f7

f3

f4f5

f6

f2

f3

f4f5

f6f2

f3

f4f5

f6

f7

f2

f3

f4f5

f7

f2

f3

f4

f5

f2

f3

f4f5

f6

f7



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Multiple Reuse Rate

Frequency reuse ratemeasurement criteria for effectiveness of frequency plan

Co-relationship : effectiveness interferences

Interaction with coverage planning

Multiple reuse rate increase effectiveness of freq. plan

1 3 6 9 12 15 18 21

safe planning

(BCCH layer)normal planning

(TCH macro layer)

tight reuse planning

(tight layer)

same frequency

in every cell

(spread spectrum)



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Multiple reuse rate

Capacity increase with multiple reuse rate

e.g. network with 300 cells

bandwidth : 8 MHz (40 radio channels)

Single reuse (4X3)

Network capacity = 40/12 * 300 = 1000 TRX

Multiple reuse:

BCCH layer: reuse =14, (14 freq.)

normal TCH: reuse =10, (20 freq.)

tight TCH layer: reuse = 6, (6 freq.)

==> Network capacity = (1 +2 +1)* 300 = 1200 TRX

cap N BW

re use

i

i

.



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The inner circle covers a smaller area, and the

frequency can be reused more tightly.

Underlaid/Overlaid Frequency Allocation

Overlaid-cellUnderlaid-cell



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Super fn

Regular fm Regular fm

Regular fm

Super fn

BCCH 15f Regular 24f Super 12f

BCCH Reuse density: 15

R TCH TRX reuse density: 12

S TCH TRX reuse density: 6

Overlaid/Underlaid Frequency Configuration

Super fn



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BCCH14+TCH36

1BCCH+3TCH

1BCCH+3TCH 1BCCH+3TCH

1BCCH+12TCH

1BCCH+12TCH 1BCCH+12TCH

1*3 1*1

1*3 and 1*1 Reuse Patterns

Fract ional Load:



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TRX1 TRX2 ... TRX7

TRX8TRX9... TRX14 TRX15TRX16...TRX21

TRX1 TRX2 ... TRX7

TRX8TRX9... TRX14 TRX15TRX16...TRX21

The red items are BCCH RCs

Illustration of 1*3 TCH Frequency Allocation


E l f 1*3 F R


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Example of 1*3 Frequency Reuse

Suppose 900 band: 96124BTS configuration: S3/3/3

BCCH layer: 96109 reuse pattern: 4*3

TCH layer: 110124 reuse pattern: 1*3


TCH C ti All ti S h


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Group 1 (MA1): 110 111 112 113 114 Cell1

Group 2 (MA2): 115 116 117 118 119 Cell2

Group 3 (MA3): 120 121 122 123 124 Cell3

TCH Consecutive Allocation Scheme


TCH I t l All ti S h


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TCH Interval Allocation Scheme

Group 1 (MA1): 110 113 116 119 122 Cell1

Group 2 (MA2): 111 114 117 120 123 Cell2

Group 3 (MA3): 112 115 118 121 124 Cell3


Relative gain for different capacity options for a 7,5


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Relative gain for different capacity options for a 7,5

MHz operator scenario.

0

12

3

4

5

6

7

8

1 2 3 4 5 6 7

1 Reference Networ k- 12 reuse, 700m site-to-site

2 Tight Macro Cel ls- 12 reuse, 500m site-to-site

3 Tighter Frequency Reuse

- MRP: 12 BCCH reuse, 6 TCH reuse- FLP : 14 BCCH reuse, 20% HW load

4 Dual Band, (10 MHz 1800)- 12 reuse and co-siting 900/1800- 25% and 100%DB MS penetration

5 Macro - Micro cel l- Micro - 200m site-to-site- 2 and 4 TRX / micro cell

6 Half Rate- 25% and 100% MS penetration

7 Adapt iveMul t i Beam Antennas- 1/1 reuse with 60% HW load- 20% and 100% of sites use AMBA

Relative Capacity Gain


S t R F i


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Spectrum Re-Farming


A spectrum re-farming is common nowadays to prepare a GSM network to

support an implementation of a new WCDMA network, this is possible to

be implemented in most common GSM frequency bands

IMSI TMSI b d P i


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Confidential Do not share without prior permission Figure 3 - 62

A paging block can fit two IMSI pages or four TMSIpages or a combination of one IMSI and two TMSI

IMSI IMSI

IMSI

T T TT

T T

T = TMSI

IMSI or TMSI based Paging

N f ll i LA d P i C d


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No of cell in LA and Paging Command

Codec Modes Circuit Quality


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Codec Modes- Circuit Quality


Support FR, HR, EFR, and AMR codec modes.A codec configuration contains codec mode adaptation thresholds and

quality graphs for circuit quality indicators

FER or Frame Erasure Rate: The number of frames in error divided by the

total number of frames

BER or Bit Error Rate: BER is a measurement of the raw bit error rate in

reception before the decoding process

.

MOS or Mean Opinion Score: Voice quality can be quantified using mean

opinion score (MOS). MOS values can only be measured in a test laboratory

environment. MOS values range from 1 (bad) to 5 (excellent).

Different voice codecs have slightly different FER to MOS correlation since the

smaller the voice codec bit rate is, the more sensitive it becomes to frame

erasures.

Adaptive Multi Rate


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Adaptive Multi Rate


Channel Source codec bit-rate

AMR-FR

12.2 kbps (GSM EFR)

10.2 kbps

7.95 kbps

7.40 kbps

6.70 kbps

5.90 kbps

5.15 kbps

4.75 kbps

AMR-HR

7.40 kbps (IS136 EFR -

TDMA)

6.70 kbps

5.90 kbps

5.15 kbps

4.75 kbps

AMR-WB

12.65 kbps

8.85 kbps

6.60 kbps

The multi-rate speech coder is a single

integrated speech codec with eight source

rates from 4.75 Kbps to 12.2 Kbps, and a

low rate background noise encoding

mode. The speech coder is capable of

switching its bit-rate every 20 ms speech

frame upon command. Unlike previousGSM speech codec (FR, EFR, and HR)

which operate at a fixed rate and constant

error protection level, the AMR speech

codec offers the possibility to adapt the

error protection level to the local radio

channel and traffic conditions

GPRS/EDGE


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GPRS/EDGE

Confidential Do not share without prior permission

Packet service based on Multiple TS shared between usersGPRS ( Based on CS- Coding Scheme )

EDGE ( Based on MCS Modulation and Coding Scheme )

EDGE2 EDGE Evolution ( Based on DBS-DAS )

Link Adaptation is used to change user throughput according to radio conditions

Different GPRS/EDGE configurations may be defined for transmitter andterminals. ( Packet Call supported on Common Configuration)

Slide 66 of 2


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Common Resource Pool


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BTS BSC

PDCH TCH


TS

TS - Time Slot, BTS - Base Transc eiver Station, BSC - Base Station Con troll er

BCCH - Broadcast c hannel, CCCH - Comm on c ontrol ch annel, PDCH - Packed d ata

channel, PCCCH - Packet comm on co ntrol channel

0 1 2 3 4 5 6 7

CarrierFrequencies

BCCH- PDCH not carrying PCCCH

- PDCH carryin g PCCCH

-CCCH, TCH or free tim e slot

Channel Reservation


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Channel Reservation

MS1 MS1

TBF

PSET1 PSET2

PDCHs

TBFlimit

to GPRS idle list

TBF

PDCHs

MS1MS1

MS5

MS5MS3MS4 MS3

MS3MS2MS2MS2

MS6 MS6MS6

Codec Selection & Link Adaptation


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Codec Selection & Link Adaptation

Codec Selection is according to CQI ( Channel Quality Indicator )CQI Can be calculated based on C/I by Receiver and sent to system as

feedback.

Documents

GSMGPRSEDGE Planning Overview.pdf