45977861 GSM Network Planning and Optimization Single Site Verification Work Guidebook V1 0

Internal Use Only▲

GSM Network Planning and Optimization Single Site Verification

Work Guidebook

Version: V1.0

Released by GSM Network Planning and Optimization

Department of Engineering Service Division of ZTE

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used

except in accordance with applicable agreements.

GSM Network Planning and Optimization Work

Guidebook

Version introduction:

Version Date Writer Assessor Translator Amendment records

V1.0 2009-07-

21

Jiang Yi Chang

Haijie, Yu

Liyun, Su

Shaoli

Lu Yan This document clarifies its

relationship with another

document named Hand-over

Standard of Project Installation

and Test of BSS and Network

Optimization in aspect of

general verification part. It

emphasizes that the verification

items can be adjusted according

to the results of project quality

examination.




Key words:

GSM; single site verification; DT; CQT

Abstract:

This document introduces the tasks of single site verification, including the general test

flow for single site verification, preparations for test, purposes for different test items,

test methods, and methods for problem analysis and problem handling. Besides, this

document also provides the standard for single site verification and the frequently-used

templates for a verification report.

Abbreviations:

SSV ：Single Site Verification

DT：Drive Test

CQT：Call Quality Test

RxLev：Receive Level

RxQual：Receive Quality

References:

Hand-over Standard of Project Installation and Test of BSS and Network Optimization

GSM P & O Radio Network Test Work Guidebook

GSM P&O Crossed Antenna Connection & Solutions

GSM P&O Network Speech Quality Problems & Solutions

(E)GPRS Radio Network Optimization Work Guidebook




Contents

Figure 1-1 The position of single site verification in the whole project 2............................................IV

Figure 1-2 The outline of this document 2................................................................................................IV

Figure 2-3 The workflow of single site verification 4...............................................................................IV

Figure 3-4 A figure of test routes for site verification in urban areas 9.................................................IV

Figure 3-5 A figure of test routes for site verification in suburban areas 10.........................................IV

Figure 4-6 Check the basic network parameters of the site through system message 3 14.................IV

Figure 4-7 Check the CA list of the cell through system messge 1 15....................................................IV

Figure 4-8 Test results of reversely connected sector of the site 17........................................................IV

Figure 4-9 Test results of reversely connected TCH antenna 18............................................................IV

Table 3-1 Calling methods which are frequently used by CS service 7.................................................IV

Table 4-2 The most common items of GSM single site verification 12..................................................IV

Table 4-3 Static power level parameters 22..............................................................................................IV

Table 5-4 Acceptance standards for the most familiar check items 30..................................................IV

1 Overview ....................................................................................................................................................... 1

1.1 Terminologies and definitions ............................................................................................................... 1

1.2 The significance of single site verification ........................................................................................... 1

1.3 Outline ................................................................................................................................................... 2

2 The workflow of single site verification ..................................................................................................... 4

2.1 Workflow ............................................................................................................................................... 4

2.2 Explanations of the workflow ............................................................................................................... 4

3 Preparation work for single site verification ............................................................................................ 6

3.1 Preparation of tools ............................................................................................................................... 6

3.2 Define the test methods and test routes ................................................................................................. 7

3.2.1 Define test methods ..................................................................................................................... 7

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. I


3.2.2 The definition of test routes ........................................................................................................ 8

3.2.3 Other preparations ..................................................................................................................... 10

3.3 Check the configuration of parameters ............................................................................................... 10

3.4 Check the site status ............................................................................................................................ 11

4 Verification test and analysis .................................................................................................................... 12

4.1 Basic verification ................................................................................................................................. 13

4.1.1 Purposes of the verification ....................................................................................................... 13

4.1.2 Verification methods ................................................................................................................. 13

4.1.3 Methods of problem analysis and problem solving .................................................................. 15

4.2 Antenna and feeder verification .......................................................................................................... 16

4.2.1 Purpose ...................................................................................................................................... 16



4.3 Verification of call completion between the calling side and the called side ..................................... 18

4.3.1 Purpose ...................................................................................................................................... 18



4.4 Verification of received signal level .................................................................................................... 21

4.4.1 Purpose ...................................................................................................................................... 21



4.5 Verification of reception quality .......................................................................................................... 23

4.5.1 Purpose ...................................................................................................................................... 23



4.6 Verification of handover ...................................................................................................................... 25

4.6.1 Purpose ...................................................................................................................................... 25



4.7 Verification of PS service .................................................................................................................... 27

4.7.1 Purpose ...................................................................................................................................... 27

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. II




5 Acceptance standard for single site verification ..................................................................................... 30

6 A single site verification report ................................................................................................................. 32

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. III


Figure contents

Figure 1-1 The position of single site verification in the whole project....................................................2

Figure 1-2 The outline of this document........................................................................................................2

Figure 2-3 The workflow of single site verification......................................................................................4

Figure 3-4 A figure of test routes for site verification in urban areas........................................................9

Figure 3-5 A figure of test routes for site verification in suburban areas................................................10

Figure 4-6 Check the basic network parameters of the site through system message 3........................14

Figure 4-7 Check the CA list of the cell through system messge 1...........................................................15

Figure 4-8 Test results of reversely connected sector of the site...............................................................17

Figure 4-9 Test results of reversely connected TCH antenna....................................................................18

Table contents

Table 3-1 Calling methods which are frequently used by CS service.........................................................7

Table 4-2 The most common items of GSM single site verification..........................................................12

Table 4-3 Static power level parameters......................................................................................................22

Table 5-4 Acceptance standards for the most familiar check items..........................................................30

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. IV


1 Overview

1.1 Terminologies and definitions

Single site verification involves with the test and verification of single site equipment

functions. The purpose is to ensure that the basic functions and radio performance of

each cell under the single site are at a normal operation state.

Usually, the network test enginner is in charge of single site verification. The task is to

verify some basic functions of the testing cells through DT and CQT, including

coverage, access, calls, and data downloading, and so on. If the functions of a site

perform well, there will be a single site verification report, which means an end of

verification. If a site has some problems, efforts should be made to analyze the

problems and to make some adjustments. Then, there will be a verification report when

the functions perform well.

1.2 The significance of single site verification

Single site verification is at the first stage of network optimization for projects like new

radio network construction, network capacity expansion, and network swap. Through

single site verification, it is possible to identify a series of obvious radio network

problems like access problems, call drops, and so on, which are caused by equipment

performance or coverage problems. The purpose is to ensure that each site which has a

formal access to the network can have good service performance and to avoid drastic

network quality fluctuations when a new network is constructed or the network

capacity is expanded.

Single site verification can help a network optimization engineer to familiarize himself

with some information in the area, for example, radio environment, site distance, and

so on, which lays a solid foundation for cluster optimization in the future.

The position of single site verification in the whole project is shown in figure 1-1.

Single site verification follows the stage of single site commissioning test/check. When

is is confirmed that each cell in the area has completed its single site verification, the

single site verification of the area is completed, and it is time to move to the next stage,

that is, cluster optimization.

This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. 1


Figure 1-1 The position of single site verification in the whole project

Besides, since single site verification is the start of network optimization, it should be

ensured that the single site project/commissioning test stage has been successfully

completed and there are no obvious problems left. The purpose for this confirmation is

to make sure that single site verification can be smoothly carried out.

For details of project optimization take-over, please refer to a guidebook called Hand-

over Standard of Project Installation and Test of BSS and Network Optimization.

1.3 Outline

The outline of this document is shown as follows:

Figure 1-2 The outline of this document

Chapter 2 clarifies the workflow of single site verification. Besides, it explains tasks

for different procedures, including preparations for the verification, verification test,

and verification criteria and so on.

Chapter 3 introduces the preparation work for single site verification.



Chapter 4 introduces the common verification items, and it also clarifies what the

tesing methods are like and how the problems which occur during test are analyzed.

Chapter 5, 6 introduces respectively the common criteria of test acceptance and the

output of a verification report, which are relevant to project verification.

The contents of the appendixes are as follows:

The appendixes consist of two parts: The first part is an existing template for

verification report, which can be used at the work field to write a report; the second

part introduces TEMS verification test, which is a frequently-used software, and

OMCR data analysis guidance.



2 The workflow of single site verification

2.1 Workflow

Figure 2-3 The workflow of single site verification

2.2 Explanations of the workflow

Before the network optimization team starts to do the single site verification, it should



be ensured that project installation, and commissioning test have been completed, and

OMCR has shown that site equipment works properly.

Preparation work for single site verification

Prepare tools: Make sure that the test software and test equipment work properly.

Define test methods: Make it clear to the client about test methods and tasks. For

example, make it clear which test methods will be used together (Idle + long call + PS),

and clarify the details.

Define test routes: Make clear the test routes for sites on basis of different scenarios.

Check parameter configuration and confirm site status: Check site parameters and

confirm site status to ensure that the basic data at OMCR is configured correctly, the

site works properly, and there are no obvious alarms.

Single site verification

Single site verification is mainly completed through CQT, and DT. The important thing

is that it should be ensured that before the specific test no obvious problems appear in

the basic verification and antenna and feeder verification. Otherwise, a series of

following tests will be meaningless.

Make an analysis to check whether it meets the single site verification

requirements or not.

Make a statistical analysis of the verification test at OMCR in relation to the items and

functions which need to be verified. The judgment should be based on the requirements

of the client. If the verification meets the requirements, a verification report can be

produced. Otherwise, an analysis should be made about the problems which appear in

the verification, and an adjustment work order should be produced.

Produce a single site verification report

If the site verification shows that all the requirements are satisfied, a verification report

should be produced as required.



3 Preparation work for single site verification

3.1 Preparation of tools

Single site verification is mainly completed through tests. Therefore, before the

verification starts, it is necessary to communicate with the client about the verification

methods, including the testing system and tools to be chosen.

Make clear the testing system and testing handset

The frequently-used testing systems include TEMS, Pilot Pioneer, Nemo, and so on. At

the same time, it is necessary to make clear what kind of testing handset will be used

and how many testing handsets are needed for each testing system (it depends on the

testing method). The most frequently-used testing handsets include Sagem, Sony

Ercssion, and Nokia. What’s important is that if PS verification is required by the

client, it should be confirmed whether the MS used supports EDGE service or whether

the MS multi-timeslots ability can satisfy the acceptance standard for PS downloading.

For example, upon the verification, it is requested that the fixed point downloading rate

shoud be higher than 100Kpbs (>100Kpbs), then the terminal used must support EDGE

service and 4＋1 multi-timeslot ability at least.

Make clear which OMCR software will be used to analyze the test data

Besides, if it is required to create some statistical graph or geographical graph in the

single site verification report, it should be clear which background analysis software

will be used to import the testing log and to analyze the data, and which color code will

be used, and so on.

For the preparation of some specific tool, please refer to User Manual or the guidebook

for test tools. In this document, Appendix Error: Reference source not found clarifies

the specifications of TEMS verification test and OMCR analysis for reference.

The frequently-used guidebooks of test tools are as follows:

A Guidebook for How to Use TEMS to Check CS Service



A Guidebook for How to Use TEMS to Check EGPRS Service

A Guidebook for CDS (E)GPRS Test from GSM Network Planning and Optimization

Department

3.2 Define the test methods and test routes

3.2.1 Define test methods

Before the single site verification starts, it is necessary to communicate with the client

and make clear the test methods. The test methods mainly involve with the following

parts:

Calling methods adopted by CS service

Usually, a combination of two calling methods will be adopted for the test, for

example, Idle + short call, Idle + long call, or Idle + short call + long call. Each

test method has different emphases. For details, please refer to table Table 3-1:

Table 3-1 Calling methods which are frequently used by CS service

Test methods Purposes

Idle It is used to record the network condition at idle state and

the level and C/I on BCCH

Short call It is mainly used for testing the accessibility and mobility

of network.

Long call It is mainly used to test the retainability and mobility of

network.

For short calls, it is necessary to confirm some information with the client,

including the length of a short call, the interval between two short calls, and the

length of waiting time when a call is originated abnormally or a call drop

occurs.

For short calls or Idle state, it is necessary to confirm whether the test is based

on fixed BCCH.

Test methods for PS service

If EGPRS service is commissioned for a network, PS service performance test

should be done upon site verification. The most common test items include

attach, PDP activation, FTP download/upload, ping test, and so on.



Besides, other information should also be confirmed, including whether it is

fixed point test or drive test, whether GPRS service test and EDGE service test

should be carried out independently, what the size of document downloaded or

uploaded by FTP, which protocol will be used (APP, LLC, RLC) as the

acceptance standard of throughput.

3.2.2 The definition of test routes

The choice of test routes varies with different scenarios of site verification. The test

scenarios are usually divided into two categories, that is, urban areas and suburban

areas. This classification is based on distribution density of sites and the surrounding

radio environment.

Urban areas

Usually, urban sites refer to dense urban sites/mean urban sites. The average site

distance of the surrounding sites is among the range of 300m-1000m (it depends on

different network environment). The main features of test routes in urban areas are as

follows:

a. The test routes should cover the roads which are covered by different

sectors of the sites to be tested. Besides, the main streets around the base

stations should also be included.

b. The test routes should reach the areas covered by cells which are around

the base stations to be tested so as to ensure that the actual coverage area

of the site and its handover functions can be verified.

c. The design of test routes should take into consideration the local customes

of travel so as to reduce the waiting time at traffic lights.

Figure Figure 3-4 shows a classic test routes for single site verification in urban areas:



Figure 3-4 A figure of test routes for site verification in urban areas

Suburban areas

Normally, suburban sites refer to suburban sites/rural sites. The average site distance of

the surrounding sites is among the range of 1－5Km, and there are only wide roads

around. The main features of test routes in surburban areas are as follows:

a. The test routes should cover the roads which are covered by different

sectors of the sites to be tested.

b. The test routes should reach the overlapping areas of surrounding neighbor

cells so as to ensure that the actual coverage area of the site and its

handover functions can be verified.

c. For isolated sites, the normal coverage area of the site should be got

through the test.

Figure Figure 3-5 shows a classic test routes for single site verification in suburban

areas:



Figure 3-5 A figure of test routes for site verification in suburban areas

3.2.3 Other preparations

Besides, it is necessary to confirm the following items with the client:

Get the customized SIM card for test from the client.

If PS service needs to be verified in single site verification, it should be ensured

that the IP address, user name, and pass word of ftp sever are got.

Get the digital map which is in form of MapInfo.

3.3 Check the configuration of parameters

Before the site verification, engineers responsible for single site verification need to

check the configuration of OMC parameters of the site to be tested. The purpose is to

avoid the possible verification failure cuased by incorrect data configuration.

The check of parameters can be quite flexible. One method is to export the

configuration table of radio parameters through OMCR and compare it with the

planning data. Or the parameters can be checked directly at OMCR.

Usually, the check of parameters includes but is not limited to the following items:

1. For basic network parameters, it should be checked whether MNC, MCC, LAC,

RAC, CI, BCCH, NCC, BCC are configured according the planning.

2. It should be checked whether the site configuration is correct and whether the

number of carrier frequency of each cell is the same as that in the planning.This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. 10


3. It should be checked whether the frequency points of each cell’s BCCH, and TCH

are configures as planned. If frequency hopping is configured for TCH, the

parameters related to frequency hopping should be checked, including MA,

MAIO, HSN, and so on. Besides, it should be confirmed whether TSC of each

channel is in consistent with BCC.

4. It should be checked whether the neighbor cells of each cell are configured as

planned, and whether the definition of external neighbor cells is correct.

5. It should be checked whether the channels of each cell are configured as planned,

especially the number of SDCCH channels, the quantity and locations of PDCH

channels.

6. Other network parameters should also be checked, including the minimum access

level, whether C2 algorithm is enabled or not, DTX, and so on. The check should

follow the template of site planning of radio parameters.

3.4 Check the site status

Finally, before the single site verification, the site status should also be checked so as to

ensure that the site works properly.

1 It should be confirmed whether the project commissioning is completed, and

whether the single site verification is completed. The single site verification is

carried out by engineers responsible for single site verification. The main task is

to do call quality test. Through the single site verification, it can be ensured that

the site can provide the basic call service.

2 OMCR alarms should be checked, including the current alarms, and history

alarms. If the following alarms exit, it is necessary to communicate with BSS

engineers to manage to solve the problems before the verification test starts:

Broken link of LAPD, broken link of TRX, TRX hardware alarms, transmission

alarms, VSWR alarms, clock alarms, and so on.

3 Before the verification, it is necessary to check the basic KPI of base station

through OMCR. The purpose is to ensure that the availability ratio of SDCCH,

and TCH is at a normal state, and that some traffic already exists.



4 Verification test and analysis

Single site verification usually consists of the following items: Basic verification,

verification of antenna and feeder connection, downlink coverage level, downlink call

quality, call functions, handover functions, and PS service, and so on.

During the process of verification test, some abnormal phenomena need special

attention. For example, originating call failure, handover failure, call drop, poor voice

quality, and so on. These events may probably reflect all kinds of network problems

behind. For those obvious abnormal events, it is suggested that they should be analyzed

carefully, and be solved at the phase of single site verification if possible.

Besides, single site verification items may vary with different kinds of projects. For

example, the single site verification for a swap project should compare items like

coverage and quality before and after the swap.

Table 4-2 shows the most common single site verification items.

Table 4-2 The most common items of GSM single site verification

Verification items Purposes Compulsory

or optional

Basic verificaiton Verification of site engineering parameters

(longitude and latitude, antenna height, and so on)

Verification of key radio parameters in system

messages at idle state

Compulsory

verification of

antenna and feeder

connection

To confirm whether the coverage direction of BCCH

is the same as planned.

To check whether BCCH, TCH antennas are

connected in a reverse way.

Compulsory

Verification of the

calling and the called

function

To verify the calling and the called functions to see

whether there are calling or called failures.

Compulsory

Verificaiton of

received signal level

To check whether the downlink coverage level is

normal and whether the coverage area is normal.

Compulsory

Verification of

received signal quality

To check whether the downlink call quality is normal

and whether inside network interference exists.

Compulsory

Verificaiton of

handover functions

To check whether the handover functions and

neighbor cell data are reasonable.

Compulsory



To check the uplink received signal level and quality.

Verification of PS

service

To verify Attach, PDP activation

To verify FTP download and upload

Optional

4.1 Basic verification

Note

According to the requirements in the document named Take-over Procedures from

Project Installation and Commissioning of BSS Side to Network Optimization,

engineering parameter verification, CQT, antenna and feeder check, and so on should

be done before the optimization so as to ensure that the site works properly. In

consideration of the fact that the quality of enginnering supervision in some projects is

not so high, therefore some basic problems can not be excluded. In other words, at the

phase of single site verification, the basic engineering parameters, radio parameters,

and antenna and feeder system should be verified. For those projects whose

engineering supervision turns out to be quite good, it is suggested that the basic

verification can be simplified to some extent.

4.1.1 Purposes of the verification

The basic verification starts as soon as engineers arrive at the site which is to be

verified. The purpose is to ensure that the basic engineering parameters and radio

parameters of site (cells) are configured correctly. If problems appear at the phase of

basic verification, they should be solved first. Otherwise, the follow-up verification

work will be meaningless.

4.1.2 Verification methods

The verification of engineering parameters includes the following items:

Check whether the longitude and latitude of the site is correct. If it is found that

the difference between the actual longitude and latitude of the site and the

planning data is more than 100M (>100M), the longitude and latitude information

should be modified. Besides, the network planning engineers should know the

modification.

Check whether there is any obvious difference between the actual antenna height

and the planning data through eye measurement.



Check whether antenna is shooting the air or there is no mechanical downtilt at all

(However, according to the plan, there should be mechanical downtilt.).

The verification of radio parameters mainly aims to check whether the contents of

system messages of testing handset at idle state are the same as those of planning data.

The purpose of this task is to ensure that the key system parameters of OMCR are

configured correctly. At the same time, it might be found that OMP data and OMCR

data of BSC are not consistent. The parameters to be checked are as follows:

Check whether the basic network parameters are configured correctly, for

example, MNC, MCC, LAC, RAC, CI, BCCH, BSIC, AccessMin, CRO，T3212,

and so on.

System message 3 can be opened through the test system to confirm whether the

contents there are the same as those of planning data. The following figure shows

the specific contents of the message:

Figure 4-6 Check the basic network parameters of the site through system message 3

Check whether CA list of the cell is configured correctly.

The CA list of the cell refers to all the frequency points configured on BCCHs,

and TCHs, which can be seen clearly in the descriptions of channels if system

messge 1 of test system is opened.



Figure 4-7 Check the CA list of the cell through system messge 1

4.1.3 Methods of problem analysis and problem solving

1. The main cause for engineering parameter problems is due to the fact that the

project installation and commissioning are not carried out according to TSSR

reports. If there are problems with longitude or latitude, it may be due to the

possibility that the data of engineering investigation are not recorded correctly.

If it is found that the longitude and latitude of the site are not correct, it should

be confirmed that whether the site is the one to be verified (through CI data of

the cell). Then the longitude and latitude information of the site should be

confirmed with the planning staff. If it is true that the information of longitude

and latitude is not correct, it is suggested that the person responsible should tell

the planning staff the correct information, and ask them to update it.

If there is a big difference between the actual antenna height and mechanical

downtilt and those of the planning data, the problems should be reported to the

engineers to make some corrections. The test should come after the corrections.

2. The main cause for wrong radio parameters is that the parameter configuration at

OMCR is not correct. If so, the suggestion is that staff responsible for OMCR

equipment room should make some modifications before the test can start. In

some cases, though it does not occur frequently, it is because that OMP data are

not consist with OMCR data. In this case, this problem should be reported to BSS

engineers so as to ask them to check OMP data and OMCR data, to reconfigure

the data, and so on. Only after that, can the test start.



4.2 Antenna and feeder verification

4.2.1 Purpose

Since the radio network quality is closely related to the antenna and feeder system,

antenna and feeder verification is a necessary and fundamental part of site verification.

If the antenna downtilt is not correct, there will be some obvious problems. On the

other hand, if the antenna and feeder is connected in a reverse way, there will be a

series of problems like call drop, handover failure, and poor voice quality.


The actual coverage direction of each cell’s antenna can be checked with a

compass.

Import the engineering parameters including cell azimuth to the drive test

software, that is, the map.

It should be ensured that there is at least one testing handset which is always at the

idle state so as to record the information on BCCH. Whenever MS enters the main

coverage area of a sector, the Cell ID of the cell where MS resides in should be

paid attention to. At the same time, it should be checked whether the antenna

azimuth is consistent with the Cell ID.

If the coverage direction of each cell’s main lobe has a certain distance from the

site (100m), another handset should be used to do call quality test so as to manage

to occupy TCH carrier. It should be checked whether there is a dramatic drop of

downlink level when the handset occupies SD channel and TCH channel during

the call.

After the drive test, logfile should be imported to background anlysis software.

Then a thematic map will be produced on basis of BCCH of the cell. With the

map, it can be confirmed whether the Cell ID of each cell is almost consistent

with the coverage direction of azimuth.


1. Antenna azimuth is wrong

During the test process, it can be confirmed whether the actual main lobe direction of

each cell is consistent with the planning data (Besides, a thematic map of BCCH



coverage can help to judge whether the Cell ID of each cell is almost consistent with

the coverage direction of azimuth.). If there is an obvious difference, (>30 degrees),

and there is no sign that BCCHs of the cell are connected in a reverse way, it means

that the direction of the antenna is not right.

In this case, the problem should be reported to the engineers so as to make some

corrections.

2. Antenna is connected in a reverse way

If an antenna is connected in a reverse way, the problem can still be further classified

into 3 categories. That is, only BCCH antenna is connected in a reverse way, only TCH

antenna is connected in a reverse way, or the whole sector is connected in a reverse

way.

For reversely connected BCCH antenna or reversely connected sector, they can be

observed through the special BCCH-based map of the cell. As shown in the following

figure, there will be an overlapping area between the actual coverage area and the

planning area in bothe cases.

Figure 4-8 Test results of reversely connected sector of the site

If TCH antenna is connected reversely, BCCH signals and TCH signals of the same cell

will not appear in the same sector. If 3/4 of the carrier frequency is assigned to a

subscriber when he originates the call, it can be seen that the level of occupied TCH is



lower than that of occupied BCCH obviously. The level change during CQT will show

whether TCH antenna of the site is connected in a reverse way. Here is a picture:

Figure 4-9 Test results of reversely connected TCH antenna

For detailed check procedures, please refer to GSM P&O Crossed Antenna Connection

& Solutions.

This kind of problems should be reported to the engineers so as to ask them to do some

corrections.

Note: Since the basic verification and antenna and feeder verification are both

fundamental and necessary part of the whole procedures, it is suggested that these two

verification items shold be carried out before the follow-up specific verification work.

The purpose is to avoid unnecessary repetitive work.

4.3 Verification of call completion between the calling side and the called side

4.3.1 Purpose

In this verification test, the calling side will originate a call and the called side will go

through a call completion test. The purpose is to check the call functions of the site

between the calling side and the called side, call connection time, and the quality of

speech (monologue, call failure, and cross talk).




CQT or DT will be used to do the test. Both the handset of the calling side and the

handset of the called side will use the same drive test card. Besides, the handsets

will be used in the testing vehicle to do the test.

Usually, short call will be used for the test. It is suggested that the call duration

should be 15 seconds, and the call interval should be 10 seconds.

The calling side should originate calls repetitively, and the called side should

answer more than 10 calls. Besides, it is better that different TCH carrier

frequencie are occupied. During the test, the engineer responsible should listen

carefully to confirm whether there are problems like monologue, Bidirectional

silence, cross talk, and so on.

A statistical counting of a series of indicators, like call success rate, call setup

time, and so on. Some special events should be paid attention to and their causes

should be analyzed, for example, originating call failure, congestion, excessive

long call setup time, and the like.


During the call quality testing, if some cell has obvious voice problems, for example,

monologue, Bidirectional silence, and cross talk, the following items should be

checked:

1. Check whether there are unbalanced uplink/downlink problems, or severe

interferences;

2. Check whether there are self-loop transmission lines;

3. Check whether CIC codes of MSC side and BSC side match;

4. Check whether there is something wrong with some time slot in the transmission

circuit;

5. Check whether the configuration of time slots of the time-multiplexed equipment

is correct during shared E1 transmission;

6. Check whether the problems are casued by DRT/EDRT board failure or TIC board

failure;

For detailed check procedures and methods, please refer to GSM P&O Network Speech



Quality Problems & Solutions.

During the test, if it is found that the completion rate of some cell is low (<90%), the

following items should be checked:

1. It should be checked whether there are uplink/downlink interferences. If there are

strong uplink/downlink interferences, the calling side will hear beep sound when

he originates a call. Then, MS will return back to the standby interface (SD

assignment fails).

Uplink interferences can be checked through the statistical counting of

interference band. If Band 4 & 5 counts is found, it means that there are severe

uplink interferences.

Section Error: Reference source not found is about downlink interferences, and

this part can be used to judge downlink interferences.

2. It should be checked whether the problem is caused by network congestion. If

both the calling side and the called side have TCH congestion, the network side

will deliver Disconnect signaling, and the cause value is 34.

For those sites which are configured with a low capacity, for example, cells

configured with S2 or lower, it is common that the traffic channel will be quite

busy upon the commissioning of site. The result is that the call completion

between the calling side and the called side fails.

Operators of OMC equipment room should be asked to check the service

occupancy status of all carrier frequencies’ time slots. The purpose is to check

whether there are still channels available, or whether all the channels are

occupied.

3. It should be checked whether the problem is caused by the fact that the access

parameters are not correctly configured.

The parameters which may influence the call establishment should be checked.

If the actual configuration is not consistent with the principles, it should be

modified according to the actual situation. The parameters to be checked

include RACH minimum access level, Rxlev_Acc_Min, CBA, CBQ, and so on.

4 It should be checked whether the problem is caused by cross-connected antenna

and feeder.



If BCCH antenna or TCH antenna is cross-connected, the RX level will drop

dramatically when TCH is occupied by the handset (in comparison to SDCCH).

If the level is too low, TCH assignment may failure. The result is that there will

be problems with originating calls. For the detailed check procedures, please

refer to Error: Reference source not found section.

4.4 Verification of received signal level

4.4.1 Purpose

Check whether the downlink coverage level is normal when MS is at idle mode and

dedicated mode through the drive test (For example, check whether the level is too low

in line-of-sight coverage area which is close to the cell or whether the level of some

cell is lower than any other cell obviously.). The purpose is to check whether the

following problems exist: Carrier frequency is abnormal, antenna and feeder is

connected in a reverse way, antenna downtilt/antenna directional angle is not

configured as planned, there is obvious overshooting coverage, and so on.


The verification methods are clarified here:

Prepare the Mapinfo map which shows the site location. Choose the test radius

and test routes on basis of the site environment.

Carry out DT test and keep a test log. Pay attention to the Cell ID at Idle state so

as to ensure that MS will reside stably in the cell which is to be tested.

Pay close attention to RxLev Full (dBm) on BCCH at idle state through the test

software interface or the testing handset interface.

Pay close attention to RxLev Sub (dBm) on TCH at conversation state through the

test software interface or the testing handset interface.

After the test, the background analysis software should be used to do some

statistical counting for downlink level at idle mode and dedicated mode

respectively. Then, it is supposed to produce a GIS map which shows the

downlink level distribution.




The statistical counting of the downlink level and the GIS map which shows the

downlink level distribution will show whether there are obvious downlink level

coverage problems.

If there are problems like weak downlink level, shrinked coverage, the problems can be

analyzed and checked as follows (the check items listed here are to be carried out after

the basic verification):

1. Check the surrounding environment of the antenna of base station to see whether

there are obvious obstacles around the antenna, for example, billboards, high

buildings, high trees, glass walls and so on. If there are such obstacles, the antenna

azimuth or antenna height should be adjusted so as to minimize their influence.

2. Check whether the parameters which are relevant to access are configured

correctly, including Rxlev_Access_Min, CBA, CBQ, CRO and so on.

3. Communicate with engineers responsible for OMC equipment room and ask them

to check the configuration of data which are related to the output power of carrier

frequency. Actually, the static power level (PwrReduction) parameter of each TRX

should be checked. The purpose is to avoid the possibility that the configuration of

this parameter is so large that the attenuation of downlink transmission power is

too large. If this happens, there will be no downlink coverage.

Table 4-3 Static power level parameters

Full name Static power level

Abbreviation PwRreduction

Descriptions

This parameter represents the static power level oftransceiver. Usually

a static power control is addedon the basis of TRX transmission power

specifiedby Static power level. Namely, a restriction isadded based on

the maximum transmission power,thus to get the actual maximum

transmissionpower Pn of the TRX. The dynamic power control

isimplemented based on the maximum transmission power Pn.

Management

objectTRX

Value range

The maximum output power, the maximum output power -2dB, the

maximum output power -4dB, the maximum output power -6dB, the

maximum output power -8dB, the maximum output power -10dB, the

maximum output power -12dB, the maximum output power +1.5dB, the

maximum output power +1dB, the maximum output power +0.5dB.



Full name Static power level

Default

valueThe maximum output power

4. Communicate with engineers responsible for OMC equipment room and ask them

to check the alarms of the site. Usually, the alarms which indicate negative impact

on site coverage are as follows: Carrier frequency alarms or CDU related alarms,

for example, PA alarms of carrier frequency, 3db alarms from carrier frequency,

CDU SWR alarms, and high temperature alarms of carrier frequency. There are

also clock alarms, for example, clock loss alarms of CMM board. Besides, there

are transmission alarms, for example, broken link alarms of TRX, yellow code

alarms of transmission, and so on.

5. For a swap project, if the original antenna and feeder is reused, it should be

checked whether a tower amplifier is used before the swap. If the tower amplifier

is used, it should be confirmed whether the tower amplifier is used in a right way.

4.5 Verification of reception quality

4.5.1 Purpose

Check whether there is this kind of problem, that is, at the conversation state, the

downlink level is normal but the downlink quality is poor. At this stage, it aims to

check the obvious interferences in the network or the hardware failures.


The verification methods are clarified here:

Prepare a map named Mapinfo in advance, which shows the location of the base

station. Choose the appropriate test radius and test routes according to the site

environment.

Pay attention to the downlink quality of handset at conversation state during the

test. With the actual configuration of site in mind, it is suggested that special

attention should be paid to RxQual_Sub of BCCH carrier frequency and TCH

carrier frequency, and C/I at conversation state. Besides, it should be avoided that

the downlink level is too low at conversation state.

After the test, the OMCR analysis software should be used to do some statistical



counting for downlink level quality at conversation state. Then, it is supposed to

produce a GIS map which shows the downlink level distribution.


The main causes for poor downlink quality should be analyzed on basis of the

downlink level and downlink C/I which are measured in DT test. The common causes

for poor downlink quality include interferences inside and outside the network,

hardware failures, inappropriate configuration of neighbor cells and parameters, and so

on.

1. If the call quality is poor (RxQ > 5) and the downlink level is normal, C/I at that

time needs to be checked. If C/I is small (< 10), it is obvious that downlink

interferences exist in the cell. The interfering resources may come from inside the

network or outside the network.

For interferences from inside the network, the frequency planning of the site

should be checked through the planning software to see whether there are obvious

co-channel and adjacent channel problems. At the same time, it can be confirmed

whether the interfering resources come from the neighbor cells nearby on basis of

the neighbor cell measurement reports. If it is confirmed that the interfering

resources come from co-channel and adjacent channel interferences from inside

the network, the relevant frequency point needs frequency optimization.

Besides, for those cells where frequency hopping exists, it should be confirmed

whether the following frequency hopping parameters are configured correctly:

MA, MAIO, HSN and so on.

If there are interferences from outside the network, sweep generator should be

used to do frequency-sweep so as to locate the interfering sources. The most

familiar interfering sources from outside the network include TV station, high-

power radio station, microwave, radar, high voltage power lines, secure

conferencing equipment, interference unit at a gas station, and so on. For detailed

check procedures, please refer to GSM P & O Interference & Solutions-

Guidebook.

2. If the call quality is poor (RxQ > level 5) and the downlink level and downlink C/I

are normal, the problem may be caused by hardware failures. In this case, it

should be checked whether there are carrier frequency alarms or CDU related



alarms. For example, PA alarms of the carrier frequency, 3db alarms from carrier

frequency, CDU SWR alarms, and high temperature alarms of carrier frequency,

and so on. Besides, it should be checked whether there are problems with line

connections of radio frequency or output port of set-top unit. If the lines are not

well connected, you can feel they are quite hot.

3. Check the handover related parameters. First, check whether there is a complete

configuration of neighbor cells. If some neighbor cells are omitted, the handset

can not be connected promptly to the cell which has better signal level and quality.

Therefore, the call quality will be poor. Besides, the following parameters which

are related the cell and its neighbor cells should be checked closely: PBGT

handover threshold, level handover threshold, P/N values, and so on. The poor call

quality may be also caused by the fact that the handover between cells is not

smooth and there is an increasing amount of interferences. In this case, this kind

of parameters should be optimized so as to improve the speed of handover.

4.6 Verification of handover

4.6.1 Purpose

The purpose of this verification is to check whether there are problems with the

configuration of neighbor cell parameters and handover parameters from the

perspective of long calls. Besides, it should be checked whether there are problems like

interferences, overshooting, and so on.


Handover verification is usually carried out through long call test. Here are the details:

During the test, long call test will be adopted and the handovers on TCH channel

should be recorded.

Examine the neighbor cell list to see whether the nearby neighbor cells of the test

system are all listed out. If there are cells which should be listed out but not, it is

suggested that OMCR engineers should be asked to check whether neighbor cells

are omitted or whether there are problems with the existing neighbor cells.

The level of both the serving cell and neighbor cells should be checked to see

whether there are handover problems, for example, hysteretic handover, quick



handover, ping-pong handover and so on.

After the test, a statistical counting of handover events should be done for the test

files so as to get the successful handover rate indicator. The source cells and target

cells which are related to unsuccessful handovers derserve special attention.


During the single site verification test, if there are handover failure events, the

following items should be checked:

1. Check whether the neighbor cell data are configured as planned for each cell. If

the configuration is not right, the handset can not be connected to the cell which

has the most suitable level. The result is that there will be handover failures. It can

be checked whether the neighbor cells are configured completely and correctly

through the neighbor cell list of drive test software.

2. When handover failure occurs, the relevant source cell and target cell should be

paid attention to. It should be analyzed whether the handover is justified in aspects

of geographic topology, level of serving cell, and level of target cell. It should be

checked whether there are problems with the downlink coverage level, the

downlink quality, or the target cell.

3. If the handover failure is caused by the donwlink coverage or downlink quality

problems of the serving cell, section 4.3 and Error: Reference source not found

should be referred to.

4. If there are no problems with the serving cell, it should be analyzed whether the

location of the target cell is appropriate or whether the level of BCCH is

reasonable. Besides, it should also be checked whether the target cell has

problems like overshooting coverage or weak coverage.

5. Check whether the target cell has co-channel interferences. That is, it should be

checked whether the target cell has co-channel cells within a certain range. It is

quite possible to have continuous handover failures if there are co-channel and co-

BISC cells.

6. Check whether the handover failure is caused by the too slow handover. That’s

because interferences will increase if the handover is too slow. This judgment can

be made on basis of the level of serving cell and adjacent cells. With this kind of

problems, some parameters should be optimized to improve the handover speed, This document contains proprietary information of ZTE Corporation and is not to be disclosed or used except in accordance with applicable agreements. 26


including handover PBGT, level threshold, pre-processing, and so on.

7. Besides, it should be checked whether the serving cell and neighbor cells have

alarms related to CMM clock. This kind of alarms will lead to frequent handovers

or no handover. This kind of problems should be reported to BSS engineers to be

solved.

4.7 Verification of PS service

4.7.1 Purpose

GRPS service and EDGE service of GSM network are playing a more and more

important role now. The verification of PS service is to ensure that there are no

problems with PS service for those new sites. That is, there are no problems with data

download and data upload.


Usually, PS service adopts fixed point test (some clients may require DT test). Here are

the details:

One handset is used to do PS service test. Before the test, it should be ensured that

all the preparation work has been done. For example, it should be confirmed

whether PS service is enabled for the test card, and whether the account number

and password of the server for FTP download are got.

Choose an appropriate test place. Usually the test should cover 100 meters

covered by the cell so as to gurantee that the downlink coverage level and C/I of

the test place are satisfactory. For EDGE service, it should be ensured that C/I is

over 20 steadily.

Start the test. The single site verification test usually does not involve a lot of test

items. The relevant test items include Attach, PDP activation, FTP download,

MMS sending and reception, and so on. Each item should be tested for 10 times,

and then the average value will be recorded. For detailed procedures of PS service

test, please refer to the PS service test part in GSM P & O Radio Network Test

Work Guidebook.

The OMCR analysis software can be used to get the test results of different test

items. Some abnormal events should be paid close attention to, and be analyzed,



for example, Attach failure, PDP activation failure, slow download speed, TBF

drop, and so on.


If the single site verification results show that there are abnormal events like Attach

failure, PDP activation failure, slow download speed, TBF disconnection, engineers

who are responsible for network planning and optimization can analyze and solve the

problems through the following methods. Here are the details:

1. Check the test environment

PS service test is a point to point test. First, it should be ensured that PS service

of the test system and test handset operates well under a site which works well.

For detailed procedures, please refer to the PS service test part in GSM P & O

Radio Network Test Work Guidebook.

Besides, the test results of PS service performance can also be influenced by

FTP server performance, and its location in the network topology. This kind of

problems can also have an impact on the verification results all the other sites,

so they should be treated with special care.

2. Check the radio environment

During PS service verification, the radio environment should also be paid

attentiont to. During the test, it should be ensured that uplink/downlink quality

and C/I are good, and there are no frequent cell reselections. The purpose is to

guarantee that the verification results have nothing to do with the radio

environment.

Check data configuration

Check BSC cell parameters to confirm whether “GPRS is enabled” or “EDGE

is enabled”.

Check whether the extra abis time slots for transmission are correctly

configured for the site which is to be checked.

Check whether PDCH channels are configured for the site.

3. Check the resource configuration

Check the number of PDCH channels.



Check the time slot configuration on Abis interface.

Check DSP configuration on PC (UPPB，BPCU) board.

Check the bandwidth resource on Gb interface.

For item 2, 3, and 4, please refer to (E) GPRS Radio Network Optimization

Work Guidebook.



5 Acceptance standard for single site verification

After the verification test, the OMCR analysis software is used to analyze the test log

so as to get the KPI of the test and GIS map. The statistical counting methods vary with

different test softwares and OMCR analysis softwares. This document makes a detailed

introduction about how to use TEMS to do the test, how to export the test log, and how

to use Mapinfo to do OMCR analysis and diagrams. For details, please refer to

Appendix Error: Reference source not found.

Usually, the check items and details of single site verification for each project vary

with different requirements of our clients. However, part four of this document has

discussed the most familiar check items of single site verification. In accordance with

the most familiar check items, the following table recommends some acceptance

standards. Since the acceptance standards vary with different requirements and

different scenarios, the following acceptance standards are just for your reference.

Table 5-4 Acceptance standards for the most familiar check items

No. Name Check items Acceptance standards

1Basic

verification

Check engineering parameters

(longitude, latitude, antenna height,

and so on).

Check the following parameters at

idle state, including LAC, CI, BCCH,

NCC, BCC, BA list and so on.

Confirm whether these parameters are

configured as planned.

2Verificaiton

of antenna

Check whether the coverage

direction of BCCH is configured as

planned. Besides, check whether

BCCH antenna, and TCH antenna are

connected in a reverse way.

Confirm whether the configuration of antenna

azimuth differs greatly from that as planned.

Confirm whether BCCH antenna, TCH antenna,

or the antenna and feeder of the whole cell are

configured in a reverse way.

3 Verification

of completed

connection

between the

calling side

and the called

side

Check whether there are

unsuccessful originating calls

between the calling side and the

called side.

Confirm whether the call service between the

calling side and the called side operates well.

Check whether there are problems with voice

quality, and call setup time.

The successful call establishment rate should

be higher than 95%, and the originating calls

should be more than 10. Besides, the call setup



No. Name Check items Acceptance standards

time should be no more than 7s (both the

authentication and encryption are not enabled).

4

Verification

of received

signal level

Check whether the downlink

coverage level is normal, and whether

the coverage range is normal.

The downlink Rxlev should be around －

60dBm on the direct direction, within 100M from

the site.

For macro BTS in urban areas, samples whose

coverage level >-75dBm should reach 80％.

For sites in suburban areas, samples whose

coverage level >-90dBm should reach 80％.

5

Verification

of received

signal quality

Check whether the downlink call

quality is normal, and whether there

are interferences from inside the

network.

If there is non-hopping, and the coverage level

is larger than -85dBm (>-85dBm), the call quality

should be lower than level 2 (< level 2). If there is

frequency hopping, and the coverge level is larger

than -85dBm (>-85dBm), the call quality should

be lower than level 3 (< level 3).

If the coverage is at a normal state, samples

whose RxQual level is among 0-4 should reach no

less than 80% (≥80%), and samples whose

RxQual level is at 6 or 7 should reach no more

than 10% (≤ 10%).

6

Verificaiton

of handover

functions

Check whether the configuration of

handover functions and neighbor cell

data is reasonable. Besides, check the

uplink received signal level and

quality.

Normally, the successful handover rate should

be over 90%. Besides, there should be no

problems like ping-pong handover, no handover,

or inappropriate target cell.

8Verification

of PS service

Check Attach, PDP activation, FTP

download and upload.

Attach and PDP activation should be within 2s,

and 1.5s respectively. For FTP download speed

(when there is sufficient channel resource),

GPRS≥30Kbps；EDGE≥100Kbps*.

The sign * means that this part will vary with different projects and different

requirements of our client.



6 A single site verification report

In practice, the single site verification which the network planning department is

responsible for is the last step of network migration before the access to network is

enabled. The single site verification consists of 4 key procedures, that is, testing,

problem analysis, problem handling, and writing a report. The verification of each site

is finished with A Single Site Verification Report. If it is accepted by the client, it

means that the whole verification is successfully completed.

The verification report should include the following items:

A list of basic verification information and status confirmation.

Status of KPI related to verification test. CS service mainly includes call success

rate, handover success rate, call drop rate, coverage rate, voice quality, and so on.

PS service mainly includes Attach, PDP activation success rate, average rate of

FTP download/upload.

A GIS map of downlink level, downlink quality. The color code should be

configured according to the requirements of the client.

Analysis of special events which occur during the verification test. For example,

call failure, handover failure, call drop, and so on.

If it is a swap project, a comparison analysis of tests before and after the swap.

Other items required by the client.

Usually, the format of a single site verification report should be discussed with the

client. In the appendixes of this document, two complete templates of single site

verification are provided (template 1 and template 2). Template 1 is for a newly

established site, but the verification test of PS service is not included. Template 2 is for

swap sites, and the verification test of PS service is included.



Appendix A

A1 Templates of GSM single site verification report

The format and content of single site verification report vary with different project

requirements. The two templates provided here are based on the work field projects.

Template 1 is for a newly established site, but the verification test of PS service is not

included. Template 2 is for swap sites, and the verification test of PS service is

included.

Si ngl e si te veri f i cati on templ ate 1. rar

Si ngl e si te veri f i cati on templ ate 2. rar

A2 Guidance for TEMS single site verification and OMCR data analysis

At present, TEMS has become the most frequently used test tool for single site

verification test. The documents enclosed here make a detailed introduction about how

to use TEMS to do a series of tests, including short call, long call, frequency-sweep,

and PS service download. Besides, the templates here also introduces how to use

TEMS to export test log data, how to use Excel to do the statistical counting, and how

to use MapInfo to produce a GIS map about level, quality, throughput, and so on.

A gui debook for TEMS SSV test methods 20090516(V1. 2). rar

TEMS stat i st i cs of test data and pl ott i ng speci f i cati ons_v3. rar


45977861 GSM Network Planning and Optimization Single Site Verification Work Guidebook V1 0

Documents

Transcript of 45977861 GSM Network Planning and Optimization Single Site Verification Work Guidebook V1 0