GPRS Radio Network Planning.ppt

GPRS Radio Network PlanningGPRS Radio Network Planning

GSM Network Planning & Optimization Dept.

Objective

After completing this course, you will be able to ：• Know the principle of the GPRS network planning

• Know how to make capacity planning and coverage planning

• Know how to make GPRS frequency planning and GPRS parameter

planning

Catalog

GPRS Network Planning Overview

GPRS Traffic Distributing

GPRS Coverage Planning

GPRS Capacity Planning

GPRS Frequency Planning

GPRS Parameter Planning

Main Planning Principle

Main Planning Principle

Balance CS and PS traffic and make

development together

Take full use of the existing GSM

resource.

Keep the quality of GSM network, meet the need of GPRS

traffic


Influence of GPRS traffic

New interference from GPRS

Change of the traffic mode and planning

Short of traffic channel

Distribution of the radio resource become more complicated.

Signal load increasing

Influence of GPRS traffic


GPRS Planning Procedures

Create GPRS traffic mode

GPRS coverage Planning


GPRS frequency Planning

GPRS parameter planning

1

2

3

4

5


Catalog







GPRS traffic sort and application

GPRS traffic sort

Unconnected PTP servic

e

Connected PTP service

PTM

others

GPRS traffic application

Information on Demand

SMS based on GPRS

Inertnet explorer and

WAP

E-mail

FTP download and upload

E-trade

others


Key point of GPRS traffic mode

Key points of GPRS traffic mode

Subscriber mode

The whole volume of GPRS

traffic

Percent of different traffic

Traffic distributing by time

Traffic distributing by space

……

Traffic mode

Package length distribut

ion of each traffic

Package interval distrib

ution

…… Radio transmission mode

Distributing of coding scheme

Signaling cost

……


GPRS traffic mode calculation

On the assumption that there is no SN

DCP compression/decompression and segm

entation/reassembly （ one IP block is transf

erred as one LLC block on LLC layer ）

On the assumption that LLC is in Nack

mode

On the assumption that LLC frame is m

ade of ： LLC header(9 bytes) ＋ SNDCP he

ader(4 bytes) ＋ IP data ＋ FCS(3 bytes) ， o

ne RLC length indicator byte for each block

RLC in ack mode and 10% retransmit r

ate

On the assumption that the average le

ngth of IP package is 200 bytes.

On the assumption that IP data is conti

nues for every 10 IP packages.

M ＝「 A1 / B 」T ＝ (M ＋『 M×0.2 』＋『 M×0.1 』 ) ×20

V_IP ＝ A2 / T

V_Gb ＝ V_IP×(200 ＋ 53) / 200 ＝ 1.265V_IP

M is the min RLC blocks for the transmission of N LLC PDU

A1 is the bytes number of N LLC PDU

A2 is the bytes number of N IP packages

B is the bytes number of LLC PDU that one RLC block can bear

T is the time for the transmission of N LLC PDU

V_IP is assumed to be the bearing rate of IP layer for each PDC

H

VGb is assumed to be the bearing rate of GB for each PDCH

「 X 」 means round up (X) , 『 X 』 means round down (X)


CS-1(Kbps) CS-2(Kbps) CS-3(Kbps) CS-4(Kbps)

physical layer rate on Um

interface9.05 13.4 15.6 21.4

Bearing rate of IP layer 5.58 8.31 9.89 13.95

Bearing rate of physical laye

r on Abis interface16 16 32 32

Bearing rate of physical laye

r on Gb interface7.06 10.51 12.51 17.65

Bearing Rate of GPRS traffic


Catalog







Hopping (C/I) Non- hopping (C/I)

CS-1 7.1 10.8

CS-2 11.5 12.8

CS-3 13.6 13.7

CS-4 20.8 17.2

Allowable minimum C/I on different code scheme

Remark:

BELER=10%

GPRS coverage planning

Throughput affected by C/I using different code scheme


Procedure of GPRS coverage planning

Link budget

Calculate the maximum allowable pass loss of CS and PS (on certa

in code scheme) on certain assumption

Coverage radius calculating

According to the maximum allowable pass loss, calculate the cover

age area both of CS and PS traffic.

Coverage planning

Choose the less one as the coverage area to meet the coverage re

quirement both of CS and PS traffic. The assumption of radio environm

ent and transmission model is the same as CS traffic.


GPRS code

scheme

ratio of relative coverage

radius

CS-1 97.02%

CS-2 85.94%

CS-3 71.66%

CS-4 44.13%

PS coverage contrasted with the CS


Catalog







Procedure of GPRS capacity planning

GPRS capacity planning

Assumption of Compbell algorithm

Assumption1

On GPRS/EDGE channels ， service with different average bandwi

dth requirements at the same time are provided.

Assumption2For each request （ Session ）， data is transferred with traffic equi

valent bandwidth continuously.

Assumption3The number of PDCH requested by MS is the minimum number whi

ch can meet the bandwidth requirement.


Method of calculating the bearer bandwidth of channels on IP layer

Bearer bandwidth on IP layer for a single channel (10kbps)

LLC efficiency LLC bearer rate RLC efficiency

LLC efficiency=(signal flow+ data flow– number of data package *4)/(signal flow + data flow+ GMM/SM messages number + number of packages *10)

=LLC throughput * LLC efficiency * RLC efficiency *(1-RLC retransmission rate)

CS-1:8kbps

CS-2:12kbps

CS-3:14.4kbps

CS-4:20kbps

95%

RLC retransmission

rate

1%


Compbell algorithmGPRS capacity

planning

Procedure of GPRS signal channel planning

Calculate

the signal

capacity

according

to the con

figration o

f existing

network

Increased

load of sig

nal chann

el by each

WAP user

Increased

load of sig

nal chann

el by each

internet us

er

Calculate th

e increase

ment of tota

l signal cha

nnel after in

troduction o

f GPRS traff

ic

Determi

ne whet

her CCC

H needs

expansi

on base

d on the

network

Get the

number of

WAP user

and

internet

user from

the result

of

capacity

planning


Examples of GPRS signal channel planning


Examples of GPRS signal channel planning

Note: The above result is got based on vast of data after WAP log-on; The number of paging that needs to be added shall also conclude paging resending in CS domain caused when GPRS users in PDP ACTIVE fail to monitor PCH during data transferring.


Catalog







It’s suggested to set the PDCH on BCCH trx in initiate s

tage of GPRS development. Main advantages are: C/I can satisfy the requirement of GPRS coverage

NO extra interference to GSM traffic

Avoid the extra consideration of DTX, IUO, Hopping and PC etc.

GPRS frequency planning programme for initial network

GPRS frequency planning

Catalog







Important parameters in GPRS Planning

RAC NSEI BVCI

SPCUMUNIT BSIC FREQ

CRH TEO CRO

GPRS Cell Reselection Parameter

NMO T3168 T3192

DRX_TIMER_MAX BS_CV_MAX PAN_DEC

GPRS Cell Parameter

PAN_INC PAN_MAX

ACCESS_CONTROL_CLASS

MAX_RETRANS

GPRS Cell Access Parameter

α T_AVG_W T_AVG_T

GPRS PC Parameter ULPWCTRL DLPWCTRL

GPRS Cell Identifer

TX_INT AG MFR

PT RXLEVACCESSMI

N

Priority Delay Class Reliabilty Class

GPRS SM Parameter Peak Throughput Class Mean Throughput Class


Documents

GPRS Radio Network Planning.ppt