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Radio Network Drive Test Guide

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RADIO NETWORK DRIVE TEST GUIDE

Prepared by

Kathleen Muange Dat e 02 Jun, 2011 Approved by Dat e Version 1.0 Dat e 02 Jun, 2011

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CONTENTS

1.0 INTRODUCTION

1.1

About this document

1.2

Intended users

2.0 PROCESS FLOWCHART

3.0 TYPES OF TESTS

3.1

Optimization & Troubleshooting

3.2

Network Benchmarking

3.3

Service Quality Monitoring(Voice Quality)

4.0 PREPARATION

4.1

Introduction

4.2

Tools checklist

4.3

Network information and maps

4.4

Drive test route

4.5

Drive test schedule

4.6

Vehicle arrangements

4.7

Test methods

4.8

Configurations

5.0 IMPLEMENTATION

5.1

Positioning of test equipment

5.2

Connections

5.3

Vehicle speed during drive test

5.4

Recording of test file information

5.5

Monitored information and signaling

6.0 ANALYSIS OF TEST FILES

1.0 INTRODUCTION

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1.1 ABOUT THIS DOCUMENT

The purpose of a drive/walk test is to analyze the network system as observed by the user so as

optimize the network in problematic areas. It may be done after new installations, optimization,

before and after swaps.

This guide is designed to specify radio network drive test procedures to ensure smooth

processes, accuracy and consistency of the tested data.

For instrument usage of specific products and drive test technologies, please refer to

corresponding instrument usage guide and drive test guide.

1.2

INTENDED USERS

This guide is drafted for radio network planning optimization engineers and drive test

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2.0 PROCESS FLOWCHART

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3.0 TYPE OF TESTS

Testing can be broadly categorized into three types:

Optimization & Troubleshooting

Network Benchmarking

Service Quality Monitoring

3.1

SERVICE QUALITY MONITORING (VOICE QUALITY)

This kind of test is an end to end, subjective, end user indicator used to evaluate the

quality of the entire speech path including all network elements. It involves making test

calls across the network to a fixed test unit to assess the relative quality of various services

using Mean Opinion Score (MOS).

3.2

NETWORK BENCHMARKING

This kind of test is done to evaluate the performance of different technologies, networks or operators and service types within a given area simultaneously. Drive testing to gather networking benchmarking data is the only way mobile network operators can collect accurate competitive data on the true level of their own and their competitors technical performance and quality levels.

3.3 OPTIMIZATION & TROUBLESHOOTING

Optimization and troubleshooting information is more typically used to aid in finding specific problems during the rollout phases of new networks or to

observe specific problems reported by consumers during the operational phase of the network lifecycle.

In this mode drive testing data is used to diagnose the root cause of specific, typically localized, network issues such as dropped calls or missing neighbor cell assignments.

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4.0 PREPARATION

4.1

INTRODUCTION

Based on test objectives and requirements, determine the following:  Drive test methods

 Engineers to carry out the test.  Test area

 Instruments and devices.

For comparison tests on the same network, should adopt the same test devices and methods to

ensure the results consistent.

4.2 TOOLS CHECKLIST

The list below shows a list of tools required for a drive test but it is not limited to these. Additional tools/software may be required depending on the objective or purpose of the test.

Ite m no. Tool Available(Y/N ) Comment/ Status

1

Laptop

2

Laptop power adapter

3

Handset(s)

4

Handset charger(s)

5

Data Cable for handset

6

GPS

7

GPS Charger (if

necessary)

8

SIM Card(s)

9

DC/AC Inverter

10

DT Software installed

11

DT License (if external)

12

External antenna

(optional)

13

Scanner (if necessary)

14

Data Card(s) (if

necessary)

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Soundcard(s) (if

necessary)

4.3 NETWORK INFORMATION AND MAPS

Network information should be collected from the client before the test is started. This

data should include cell information( e.g. Site Code, Site name, BCCH, LAC, BSIC,TCH, longitude,

latitude, Hopping frequencies etc.) and engineering parameters.

Maps containing vectors such as main roads, streets, airports, lakes, rivers etc. should also be obtained (not from the client).

This data should then be imported into the drive test devices before starting the test.

4.4 DRIVE TEST ROUTE

Select drive test routes based on test scope, objectives and the client’s requirements.

Cluster drive tests should include the coverage areas of each cell and all the major roads and

streets as well as any other important locations.

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Drive test routes for single sites should include a network of roads close to the site as well as

roads far from the site ( up to extent of planned coverage distance of that sector/site). This will

ensure that there is extensive data for coverage analysis.

4.5 DRIVE TEST SCHEDULE

The schedule will be dependent on the scope of work, number of teams , test methods, targets and

other conditions and requirements from the client/operator.

4.6

VEHICLE & TIME ARRANGEMENTS

Arranging appropriate vehicles and test time based on drive test requirements

and

objectives. Specific time requirements from operator should be satisfied. For coverage comparison tests, should use the same test vehicles and select consistent test time

period.

Ensure that ports for plugging in test equipment in the car are functional before commencing the

test.

4.7 TEST METHODS

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Testing methods vary and should be determined according to operator’s specifications.

Testing methods include but are not limited to:  Long call

 Short call

 Dual mode ( e.g. If testing a GSM Network with GSM 900 & DCS 1800)  Locked on a certain technology or band (WCDMA/GSM etc.)

Long calls are dedicated mobile originating calls(MOC) that are usually 120sec long (varies

according to operators specifications). It is used to test retainability of a voice call in a

network.

Short calls are dedicated mobile originating calls (MOC) that are usually 15-30 sec long

(varies according to operators specifications). It is used to test accessibility of a voice call in a

network.

4.8 CONFIGURATION OF DT DEVICES/SOFTWARE

The following configurations should be carried out before commencing the test:

Install DT software and necessary drivers and ensure it is operating properly.

• Connect the GPS to the USB COM port and configure it using device manager

• Connect the test phone through the USB COM port and configure it as well.

• Open the drive test tool (already installed), import the maps (vector form).

Create cellfiles(site info) using network information and import into the DT devices.

Ensure all necessary configurations i.e. Frequency bands, technology, time

measurements, number of call repetitions or sequences to be used etc. are done.

Configure the parameters that you have to be notified about during the drive test e.g. handover failure, call drop, blocked calls, GPS failure, Attach,

Detach etc.

Set legends for the particular measurements required e.g. Rx Level, Rx Qual, C/I etc.

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5.1 POSITIONING OF TEST EQUIPMENT

Handset is placed in front of the drive tester for clear visibility.

GPS is placed at the front of the car or on the roof of the car if the base is magnetic.

If handset external antenna is used, it is placed on the roof of the car. Care should be taken that the antenna does not break when passing through bushy areas.

6.2 VEHICLE SPEED

DT should be carried out at speeds of 40km/h to 55km/h. In towns a speed of 40km/h is

used.

6.3 RECORDING TEST FILE INFORMATION

Save logfiles in predefined or selected folder. Each software has its own format of naming

the file and the file name may be changed to include the site name/code_sector_date if

desired.

6.4 CONNECTIONS

Connect the inverter to the car DC port. The car should be on during this time.

Connect the laptop to the power source to facilitate reliability when taking data.

Connect the GPS to the USB COM. Configuration already done.

Connect the test phone through the USB COM port.

Open the drive test tool (already installed).Imported maps and sites should already be there.

 Ensure all configurations are done.  Start recording.

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7.0 MONITORING INFORMATION AND

SIGNALLING

Various information elements and events are monitored during the test depending on the

technology being tested and the type of drive test being carried out. Signaling messages

obtained from analyzing layer 2 and/or 3 messages.

The common information elements and events monitored are shown below:

7.1 Voice call

Rx Level

Rx Quality

Interference

Dropped calls

Blocked calls

Anomalous events

Call statistics

Service level statistics

QoS information

Handover information

Neighboring cell information

Mean Opinion Score (MOS-if Voice quality test is done)

GPS location co-ordinates

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8.0 AFTER THE TEST

Post processing of data Plotting RX Level and Quality Information for overall picture of

the driven area

Initial Discussions on drive test with Local engineers

Reporting urgent problems for immediate action

Analyzing Network feature performance after new implementations

Transferring comments on parameter implementations after new changes

References

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