E1E1--E2 CM E2 CM

RF Planning and Drive Test RF Planning and Drive Test

for BSNL internal circulation only

RF Planning and Drive Test RF Planning and Drive Test

for BSNL internal circulation only

A cell can be defined

as the area covered

by one sector

Main Elements of Radio

for BSNL internal circulation only

Main Elements of Radio

Network•Mobile station

•Base Transceiver Station

RF DESIGN REQUIREMENTS

• The RF design inputs can be divided into

– Capacity requirements

• Erlang per subscriber during the busy hour–

for BSNL internal circulation only

• Quality of service for the air interface, in terms GoS

– Coverage requirements

• Target coverage areas.

• Coverage area probability

• Penetration Loss of buildings and in-cars

• Determine number of cells required for capacity

by using Erlang formula.

CAPACITY AND COVERAGE

for BSNL internal circulation only

by using Erlang formula.

• Determine number of cells required for coverage

by using propagation model.

ERLANG

• One erlang ( Erl) is defined as the amount of

traffic generated by the user when he or she

uses one traffic channel for one hour.

for BSNL internal circulation only

ERLANG TABLES

• Commonly used Erlang tables are

– Erlang B

– Erlang C

• Erlang B assumes that if calls cannot go through

for BSNL internal circulation only

then they get dropped (i.e. no queuing possible).

• Erlang C considers that if a call does not get

through then it will wait in a queue.

ERLANG TABLES

• These tables give information about the traffic

generated by X No. of TRXs for different Grades

of Service.

for BSNL internal circulation only

for BSNL internal circulation only

POSSIBLE CHANNEL COMBINATIONS

RT 0

Timeslots

RT 1

BCCH CCCH TCHSDCCH TCH

0 1 2 3 4 5 6 7

TCH TCHTCH

for BSNL internal circulation only

CM

CC SMS SS

RT 1

RT 2

RT 3

TCH

SDCCH

TCH TCH TCH TCH TCH TCH TCH

TCH TCH TCH TCH TCH TCH TCH TCH

TCH TCH TCH TCH TCH TCH TCH

FREQUENCY RE-USE

• Frequency re-use factor depends on

– the average number of the transceivers

– the total number of frequencies.

for BSNL internal circulation only

FREQUENCY RE-USE FACTOR

• If there are 3 TRX that are used per base station

and the total number of frequencies available is

27.The total number of frequencies available for

for BSNL internal circulation only

re-use is 27/3 = 9

• There are few theoretical models and many

empirical models to predict the propagation path

loss.

PROPOGATION MODELS

for BSNL internal circulation only

loss.

• Propagation models should be applied with

caution .

• Network planning tools will combine these

models with terrain data.

PROPOGATION MODELS

• For Macro Cell

– Okumura-Hata model

• For Micro Cell

– Walfisch-ikegami model

for BSNL internal circulation only

– Walfisch-ikegami model

PROCESS OF RADIO NETWORK

PLANNING

• Collection of the input parameters

• Pre planning

• Site survey

• Frequency allocation

for BSNL internal circulation only

• Frequency allocation

• Parameter planning

• The final radio network plan involves rest of the

parameters like power budget calculations and

considering path loss calculations.

OPTIMISATION

• Optimization involves monitoring, verifying and

improving the performance of the radio network.

for BSNL internal circulation only

WHAT IS OPTIMIZATION

for BSNL internal circulation only

OPTIMISATION

• Power amplifiers are located near the

transmission antennas.

• The boosters are located near the base station.

for BSNL internal circulation only

DIVERSITY

• Diversity is the most common way to improve

the reception power of the receiving antenna.

• Major diversity techniques are

– space diversity

– frequency diversity

for BSNL internal circulation only

– frequency diversity

– polarization diversity

(In our field polarisation diversity is being used)

RADIO NETWORK PLANNING

AND OPTIMIZATION

o Study of methods required for optimization:

o Traffic estimation in terms of erlangs

o Configuration of Time slots of TRX

o Calculation of frequency re use factor

o Application of suitable propagation model

for BSNL internal circulation only

o Application of suitable propagation model

o Methods to improve signal received by MS

o Study of RRM ( Radio resource management)

o Study of KPI’s( Key performance parameters)

MS BTS MSCBSC

RIL3 - CM

RIL3 - MM

RIL3 - RRSCCP

BSSMAP

DTAP

MM

TCAP

DTAP

CM

U

PSCCP

MAPI

S

SCCP

BSSMAP

BTSM

RIL 3-RR

BTSMRR

for BSNL internal circulation only

LAPD m

Layer 1 Layer 1

LAPD m LAPD

Um A bis A link BCDEFG

MTP

Layer 1Layer 1

GSM Signaling Protocols Overview

LAPD MTP

RADIO RESOURCE MANAGEMENT

• The radio resource management (RRM) is the

functions related to

– mobile location updation

– communication management issues such as

for BSNL internal circulation only

– communication management issues such as

handover and roaming procedure handling

LINK PROTOCOLS

• To execute these management functions,

information flow (traffic and signalling) takes

place via three protocols, known as link

for BSNL internal circulation only

protocols .

LINK PROTOCOLS

• LAPDm is present over the MS-BTS connection

• LAPD over the BTS-BSC connection.

• MTP is used for signalling transport over the

for BSNL internal circulation only

SS7 network.

STUDY OF KPIs

• Once a radio network is designed and

operational, its performance is monitored.

• The performance is compared against chosen

key performance indicators (KPIs).

for BSNL internal circulation only

• After fine-tuning, the results are then applied to

the network to get the desired performance.

STUDY OF KPIs

• KPls can be subdivided according to the areas of functioning, such as – area level

– cell level

– TRX level.

• Area-level KPls can include

for BSNL internal circulation only

• Area-level KPls can include – SDCCH requests

– dropped SDCCH total

– dropped SDCCH Abis failures

– outgoing MSC control handover (HO) attempts

– outgoing BSC control HO attempts

– intra-cell HO attempts, etc.

DRIVE TEST PROCESS

• Selection of the 'live' region of the network

• Selection of the drive testing path.

• To have the appropriate kits including

for BSNL internal circulation only

– Mobile equipment (usually three mobiles)

– Drive testing software (on a laptop)

– A GPS (global positioning system) unit.

USB2 USB1

Short call Long Call

USB3

Idle

Drive Test Equipments for Voice & PS callTools

1. Scanner

2. Drive Test

Software

3.UE

4.PC

5.GPS

DRIVE TEST TOOL PHYSICAL SET UP

for BSNL internal circulation only

Com 1

scanner

USB3

GPS

Data Card

PS

DRIVE TEST PROCESS

• Two mobiles are used to generate calls with a

gap of few seconds (usually 15-20 s).

• The third mobile is usually used for testing the

for BSNL internal circulation only

coverage.

• It makes one continuous call, and if this call

drops it will attempt another call.

DRIVE TEST PROCESS

• To collect enough samples at a reasonable

speed and in a reasonable time.

• If there are lots of dropped calls, the problem is

for BSNL internal circulation only

analysed to find a solution for it and to propose

changes.

OPTIMISATION SOLUTION

• Moving antenna locations

• Altering antenna heights

• Changing ARFCNs

for BSNL internal circulation only

• Antenna orientation adjustment

• Rectifying the faults in the steps followed before

finalisation of Radio network planning.

DRIVE TEST TOOL

• TEMS offers solutions for

– Planning

– Development

– Optimizing

for BSNL internal circulation only

– Optimizing

– Troubleshooting

– Expanding mobile networks

• Optimized networks mean lower operational

costs.

DRIVE TEST TOOL

• TEMS products allow efficient monitoring,

diagnosing and benchmarking in order to make

best use of available resources.

for BSNL internal circulation only

• They also enable engineers to troubleshoot

problems quickly.

TEMS CELLPLANNER UNIVERSAL

• TEMS Cell Planner Universal is Ericsson´s tool

for mobile radio network planning.

• It is a

– highly graphical

for BSNL internal circulation only

– highly graphical

– easy-to-use

– PC-based tool for design

– Realization

– Optimization of mobile radio networks.

TEMS CELLPLANNER UNIVERSAL

• It assists the user in a number of complex tasks,

including

– network dimensioning

– traffic planning

for BSNL internal circulation only

– traffic planning

– site configuration

– frequency planning.

TEMS CELLPLANNER UNIVERSAL

• It supports for

– WCDMA

– GSM 850,GSM 900,GSM 1800,GSM 1900

– iDEN

for BSNL internal circulation only

– CDMA,CDMA2000 1xRTT

– TDMA/AMPS

– NMT 450, NMT 900

– TACS, and E-TACS.

– GPRS and EGPRS (EDGE) in GSM system.

for BSNL internal circulation only