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UMTS and GSM Training Course

Version 1.1

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Actix Spotlight UMTS and GSM Training Course for Version 1.1

Edition E

The content of this manual is provided for information only, is subject to change without notice, and should not be construed as a commitment by Actix. Actix assumes no responsibility or liability for any errors or inaccuracies that appear in this documentation. Copyright © Actix 2007. All rights reserved. All trademarks are hereby acknowledged.

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Contents

INTRODUCTION ........................................................................................... 6 SCOPE OF THE COURSE .......................................................................................... 6 WHO SHOULD ATTEND THIS TRAINING COURSE?.............................................................. 7 PREREQUISITES................................................................................................... 7 AIMS OF THE COURSE ............................................................................................ 8

SOLVING COMMON NETWORK PROBLEMS WITH SPOTLIGHT ........................................ 9 ACTIX SPOTLIGHT FEATURES...................................................................................10 WHAT’S IN SPOTLIGHT? ........................................................................................11

NEW PROJECT AND TEMPLATE CREATION ........................................................... 12 CREATING A NEW PROJECT TEMPLATE ........................................................................13 NEW PROJECT CREATION (USING A PRE-DEFINED TEMPLATE):.............................................14 EXERCISE: NEW TEMPLATE CONFIGURATION.................................................................17

UMTS SECTION........................................................................................ 24

SUMMARY DASHBOARD................................................................................ 25

UMTS SPOTLIGHT REPORTS ......................................................................... 27

EVENT EXPLORER ...................................................................................... 32 ADDITIONAL FEATURES .........................................................................................35 DETAILED EVENT DIAGNOSTICS ...............................................................................37 EXERCISE: DROP CALL ANALYSIS .............................................................................39

RADIO NETWORK ANALYSES.......................................................................... 40 CELL COVERAGE ANALYSES ....................................................................................41 RADIO NETWORK EXPLORER INTERFACE ......................................................................42 EXERCISE: CELL COVERAGE ANALYSIS USING HANDSET DATA............................................44 EXAMPLE: MISSING NEIGHBORS ANALYSIS ..................................................................47 ADDITIONAL FEATURES FOR 3G NEIGHBOR ANALYSIS......................................................53 EXERCISE: 3G-2G MISSING NEIGHBORS ANALYSIS........................................................58 EXAMPLE: PILOT POLLUTION ANALYSIS.......................................................................64 ADDITIONAL FEATURES FOR PILOT POLLUTION ANALYSIS ..................................................66 EXERCISE: PILOT POLLUTION ANALYSIS USING SCANNER DATA ..........................................67

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INTERLUDE: USING CELLREFS........................................................................ 72

WORKSHOP: EXAMINING YOUR OWN DATA (OPTIONAL)......................................... 73

GSM SECTION ......................................................................................... 74

GSM SUMMARY DASHBOARD......................................................................... 75

GSM SPOTLIGHT REPORTS ........................................................................... 77

EVENT EXPLORER ...................................................................................... 82 ADDITIONAL FEATURES .........................................................................................85 DETAILED EVENT DIAGNOSTICS ...............................................................................87 EXERCISE: DROP CALL ANALYSIS .............................................................................89

RADIO NETWORK ANALYSES.......................................................................... 90 CELL COVERAGE ANALYSIS.....................................................................................91 RADIO NETWORK EXPLORER INTERFACE ......................................................................92 ADDITIONAL FEATURES .........................................................................................97 EXERCISE: NO DOMINANCE ..................................................................................101 EXERCISE: GSM VISUALIZATION............................................................................104

INTERLUDE: USING CELLREFS.......................................................................106

WORKSHOP: EXAMINING YOUR OWN DATA (OPTIONAL)........................................107

APPENDIX A: UMTS THRESHOLDS .................................................................108 SPOTLIGHT .....................................................................................................108 UMTS / SCAN_COVERAGE ...................................................................................108 UMTS / SPOTLIGHT ..........................................................................................109 UMTS / UE_COVERAGE .....................................................................................111

APPENDIX B: DATA SETTINGS FOR UMTS NEIGHBOR ANALYSES ..............................114

APPENDIX C: UMTS EVENT DIAGNOSES ..........................................................118

APPENDIX D: GSM THRESHOLDS ..................................................................129 SPOTLIGHT .....................................................................................................129 GSM / ADVANCED_HANDOVER_ANALYSIS ................................................................129 GSM / ANALYSIS..............................................................................................130 GSM / CELL_PLAN_VIEWER.................................................................................131 GSM / EVENTS ................................................................................................131 GSM / SPOTLIGHT ............................................................................................132 GSM / TROUBLESHOOTER....................................................................................133

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APPENDIX E: DATA SETTINGS FOR GSM 2G NEIGHBOR ANALYSIS............................136

APPENDIX F: GSM DIAGNOSIS .....................................................................139

APPENDIX G: GSM VISUALIZATION................................................................147

MYACTIX AND SUPPORT..............................................................................152

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Introduction

Scope of the course

The UMTS and GSM Spotlight Training Course provides a comprehensive

overview of Spotlight for the UMTS and GSM technologies. The goal of the

course is to give an understanding of the capabilities of the system and how it

can help users to improve quality of service for their network subscribers.

Advanced users will be introduced to new network applications.

The instructors for this course are experts in using Actix solutions to increase

productivity, and are familiar with the challenges faced by engineers working in

cellular/PCS environments.

Class size is limited to ensure that everyone receives extensive one on one

instruction. Participants have many opportunities to ask questions relevant to

their particular optimization needs. Upon completing the course, participants will

be able to use what they learned in class to identify and solve real network

problems.

The UMTS and GSM Spotlight Training Course begins with a high-level

presentation of the Actix platform interface and its capabilities. We will then

cover how existing optimization processes can be tailored to the specific needs

of the participants.

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Who should attend this training course?

• RF Engineers responsible for enhancing cellular performance and

implementing wireless system optimization.

• Engineers looking to further understand the application of log file

data in optimizing networks.

• Experienced technicians involved in field optimization.

• Anyone looking to maximize the return on investment in Actix

software.

Prerequisites

• Familiarity with network infrastructure and operation of the air

interface.

• A general understanding of drive test and call trace collection and

post-processing methodology and advantages/limitations with each

dataset.

• Access to Actix software and a familiarity with the Actix software

platform.

• Basic computer literacy, including familiarity with Windows and MS

Office applications.

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Aims of the course

After this course, you should be able to:

• Appreciate common network problems and how they are classified

in Spotlight.

• Configure Spotlight to work with your data and methodologies.

• Appreciate pre-defined Spotlight Reports.

• Appreciate different analyses methods (Event Based and Radio

Network Analyses) in Spotlight.

• Use Spotlight to analyze problems in data sets of differing sizes.

• Appreciate the role thresholds perform in Spotlight and how to

modify them.

From the Repository Analysis - Drilldown, you should be able to:

• Add extra data during the analysis.

• Save the project file.

• Create and save your own template for your project.

• Start Spotlight and reload the project file.

• Drilldown problem by File or Time to message level with or without

loading the whole file.

• Perform different analyses based on handset and scanner data.

• Perform 3G-2G Neighbor Analysis.

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Solving common network problems with Spotlight With the Seek-See-Solve approach, Spotlight is designed to allow you to follow

your own investigations throughout the various analysis pages and reports.

However, a typical path through Spotlight is to start from the Summary

Dashboard, examine the summary map and then the appropriate report for the

loaded data, which might indicate the presence of one or more problems.

Spotlight breaks these problems down into two groups:

• Critical issues, where an event has occurred that discontinued a

call.

• Important issues, where the quality of service has been reduced

without necessarily ending any calls.

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Cell coverage, interference problems and UMTS/GSM visualization can be

investigated from the Radio Network Explorer analyses (links to these are

shown as Important Issues in the Issues panel of the Summary Dashboard).

These then point you at specific problem events which you can examine and

diagnose using the Event Explorer (links to these are shown as Critical Issues

in the Issues panel).

Actix Spotlight Features

The following Actix Spotlight features are available for UMTS and GSM:

Radio Network Analyses • Cell Coverage Analysis (based on Scanner/Handset data)

Determines the coverage footprint of cells and identifies overshoot

against coverage design boundaries.

• Missing Neighbors Analysis (3G-3G, 3G-2G)

• Pilot Pollution Analysis (based on Scanner/Handset data)

Event-based troubleshooting • Automated root-cause diagnostics for the most common subscriber

problems such as dropped calls and call setup failure.

Reporting • Integrated, professional-quality reports including embedded maps.

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What’s in Spotlight?

• New Project and Template Creation

Provides a link to the new template configuration wizard or allows a

user to create a new project using an existing template.

• New Template Configuration Wizard

Step by step wizard that guides the user to configure a new

template with required devices, KPIs, reports, queries and so on.

• Data Configuration

Step by step wizard that guides the user to configure thresholds

and cellrefs and also select data to process into the repository.

• Summary Dashboard

From the Repository Dashboard, the user can choose to further

investigate and perform either Event based or Radio Network

analyses.

• Spotlight Report(s)

Identifies critical and important issues, and provides links to

summary statistics of the loaded data files.

• Event Investigation/Analyses

Provides a breakdown of the critical and important issues by

filename and handset identifier. These tabular pages are reached

through links on the Summary Dashboard.

• Radio Network Investigation/Analyses

Provides a breakdown of the important issues by filename and

handset identifier. These tabular pages are reached through links

on the Summary Dashboard.

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New Project and Template Creation

To create new project, click on New Project.

To open an existing project, click on Open.

To delete an existing project, click on Delete.

Comment [sf2]: Normally, if you prefer not to use Spotlight, you can always use the “legacy” Analyzer Classic link. But this is not recommended since the whole point of Spotlight , is not using Analyzer to drill down.

Comment [sf3]: Upon launch of the Actix software, the ‘Choose an Engineering Process’ dialog shows all the Engineering Processes that you are licensed to use, and so a user's software may display other processes to those shown here.

Comment [sf4]: To start a new project, click on “New Project”, otherwise you can either “Open” or “Delete” an existing project (if you have one). If you prefer to start with Analyzer Classic, click on “Classic mode”

To start Analyzer Classic, click on Classic Mode.

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Creating a New Project Template

Spotlight project templates define KPIs, reports and attributes, which are

available within a Spotlight project, and how the data is to be stored in the

repository. It is important to configure a project template correctly because it

controls not only what analysis is available, but also how the data is organized,

and this can affect the validity of the analysis.

In addition, the way you configure the project template can affect the

performance of the projects that are based on it. For example, if you include

KPIs and reports that are not relevant, performance may be slower than

necessary, particularly when creating the project and loading data into it, but

also when subsequently closing and reloading it.

Although Spotlight is based on the Repository technology, project templates are

not the same as repository templates. When you create a project template using

Spotlight's New Template option, Spotlight also generates a repository

template based on the KPIs and other options that are selected. During this

process, Spotlight uses a default repository template that is supplied with

Spotlight.

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New Project Creation (using a pre-defined template):

You can use the default repository template or an existing custom-defined

template by starting a new Spotlight project on the Creating a New Project

Step 1: Name and Template page, click on New Template. Follow the

instructions and configure your template by following the three simple steps as

below:

Step 1: Name and Template

Step 2: Preferences and Thresholds

Step 3: Choose Data

Step 1: Name and Template

1. Key in a meaningful project name.

2. Select a suitable pre-defined template.

If you prefer to create your own template, click on New Template.

3. Click Next to continue to configure your settings.

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Step 2: Preferences and Thresholds Preferences settings provide a link to the Actix Software preferences dialog.

Spotlight is a map-centric product. So, it is necessary to have a valid cellrefs file

corresponding to the drive test data.

Thresholds (See Appendix A for all UMTS Spotlight thresholds information)

are user-definable values that can be used as constants in event detection and

queries.

Comment [sf5]: All thresholds used in UMTS Spotlight are provided in an Appendix to this document.

Choose the correct cellrefs file for Actix Spotlight to refer to.

This opens the Preferences dialog. Select a cellrefs file if you have not already done so.

If you have selected a new cellrefs file, you will need to restart the Spotlight application and return to this point.

Click Next when you are done with your configuration.

3. This opens the Thresholds dialog. You do not need to make any changes here yet, but click the button to have a quick look at the dialog.

See Appendix A for all thresholds details.

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Step 3: Choose Data

Choose the data file(s) you would like to load by clicking on Add File.

You can also add the entire folder by clicking on Add Folder and/or Add all subfolders.

Click on Done to load your data files.

All file information is displayed. You can either add more files, more folders or

remove files.

Comment [sf6]: The project will be saved to this folder: \Documents and Settings\All Users\Application Data\Actix\Analyzer\Projects (depending on your current Windows user settings). For best use, aim for at least 1GB free disk space per project. Spotlight support max populated data volume: 3Gb

Click on Done to begin your troubleshooting. Actix Software will first save the Settings and Thresholds as part of the project. The progress bar for data processing will appear and this will give you an idea of how long it will take.

Note: The entire process of loading data is dependent on the volume of data to

be loaded into the project. However, once the data has been loaded into the

Repository, it can be reattached very quickly.

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Exercise: New Template Configuration

Start a new Spotlight project and on the Creating a New Project Step 1:

Name and Template page, click on New Template. You then need to fill out

options on four pages as follows:

Step 1: Choose Name and Starting Template

Step 2: Choose Devices

Step 3: Choose KPIs and Reports

Step 4: Choose Attributes

Step 5: Choose Global Filters

In this exercise, you will be creating your own UMTS Template and define all the

related devices (handset and/or scanner if you have them), KPIs, Reports,

Queries and Attributes. Let’s start by creating a template as shown below:

Step 1: Choose Name and Starting Template 1. Key in a meaningful Project Name.

2. Click on New Template to create your template.

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3. Key in a meaningful Template Name for easy access in the future.

4. Choose a template you would like to base the project on by clicking on Based on Template.

5. Click Next to start to create your template.

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Step 2: Choose Devices By default, all devices are aggregated into one device (ALL). In this page, you

can define your devices. Click on Add Device. Enter the Device Name and the

related Filter that identifies the stream of interest within the logfile.

Choose a meaningful Device Name. Actix software determines whether data

from a stream should be loaded into the Device based on whether the Filter

text matches any text in the data stream name. For example, if you have

TemExp (1) and TemExp (2) in your logfile, Filter 1) uniquely identifies the

handset stream in the file, while using an identifier that is common to many

types of logfiles. If the Filter field is left empty, data from all streams will be

loaded into the device.

1. Add a Device if you would like to define your own devices

3. Key in the Filter to uniquely identifies different devices.

2. Key in the Device Name.

4. If have a different format or device, click on Import From File to add your device filter(s).

5. Click Add when you have finished adding the device.

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Step 3: Choose KPIs and Reports You can choose the Key Performance Indicator (KPI) and Reports needed from

these three columns (select whichever applies):

Event KPIs

Radio Network KPIs

Summary Report

For this exercise, select or check on all UMTS Event & Radio Network KPIs

and the related UMTS reports. To ensure best load time performance, do not

forget to uncheck other options you do not require. Click Next> to continue.

Choose the appropriate Event KPIs, Radio Network KPIs and Reports.

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Step 4: Choose Attributes In this step, you can add more binned attributes to the set of default attributes

available in the repository. You can also configure location binning settings in

this page.

For this exercise, choose all UMTS-related binned queries and UMTS attributes

required for your template by checking the checkbox on the left of the Attribute.

Click Done when you’ve finished.

1. Choose your required binned Data Queries.

3. Configure the binning method.

2. Select all the required attributes.

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Step 5: Choose Global Filters The fifth step in creating a new Spotlight project template involves choosing

whether to enable File/Stream, Time and regional filtering in the project. If

these options are enabled, you can activate or modify them by clicking on the

Global Filters link in the top right of a Spotlight analysis page.

Note that the regional filtering option is not shown in the above example.

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After clicking Done on the fifth page, you are returned to the New Project start

page, where the new template appears in the list of project templates. Note that

for convenience, Spotlight appends the date on which it was created to the

project template's name.

Select your new template. Click Next> to continue to select the cellref file, and

change the settings and configure thresholds, as described in Step 2 and

Step 3 in page 15.

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UMTS Section

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Summary Dashboard The Spotlight Summary Dashboard provides you a quick overview of the data

loaded in the current Repository project on a per device basis. If you have

configured multiple devices during the template configuration phase, a separate

tab per device will be displayed on the dashboard. The Summary Dashboard

consists of these main components:

Dashboard provides you a quick overview of the data





Click on Log Files to display all information regarding the data file(s) you’ve loaded.

Click on Event Explorer to drill down to all Event-based analysis such as Dropped calls, Call setup Failures etc.

Click on Radio Network Explorer to investigate all Radio Network problems and perform wide-area coverage-based analyses.

Click on Report to generate your UMTS Spotlight Report based on the configuration and settings you’ve defined. The report consists of RF parameter charts and maps with important events and attributes.

The Map is the main integral part of Spotlight interface, where it shows the entire drive with Uu_Scan_RSSI being the default attribute is plotted. The cell wedges are colour coded: Green represents site that were serving during part of the drive.

The UMTS Issues panel lists all critical and important issues occurring in the dataset. It allows you to investigate further and drill down to issues in more detail by clicking on the link of the KPIs. The Critical Issues section provides an overview of the drive in terms of failure events. The Important Issues section includes the radio network analyses.

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At the top of the page, the navigation bar allows you to move around in

Spotlight. It also provides some useful functions from any stage of your

analysis:

If your current project uses Global Filters, a related link appears in the

navigation bar. Click on the link to show a dialog similar to this:

This dialog allows you to specify any files or streams that you want to exclude

from the analysis, and also allows you to filter by time (not shown above). Once

you have specified the filter, note that you need to click the Add Filter link on

the right to create the filter. If you have configured regional filtering, this dialog

will also give you the option to filter by region.

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UMTS Spotlight Reports Reports are a good place to start when attempting to identify problems in the

loaded data. These can be accessed by clicking on the Reports link from

Spotlight's Summary Dashboard page.

Note: A report must have been activated in the current project's template. It

shows all unfiltered data in the project database for the associated technology.

You can either click on the Save button to save report in .htm format or click on the Show Excel Report button to open the report in Microsoft Excel.

To close the Report, click here. To switch views, use the Window menu.

Click on one of the reports in navigation tabs such as Report, Overview, Overview Map, Radio, CS Domain and PS Domain to explore various pages of the report.

If you run the report again on different data, the map bitmaps will be updated to

reflect the new data. If you then reopen the workbook that was saved earlier,

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Excel asks if you want to update. Choose the Don't Update option, or the maps

will be updated with the data from the latest running of the report.

The Save button exports the report as a web page. Note that the web page has

an associated subfolder with a unique name containing various image and other

files relating to that report. However, the image files in each subfolder are

always called image1.gif, image2.gif, which may cause you problems in some

situations.

To close the report, click on the X on the far right of the application menu

options. If you have a map also open, you can switch between the report and

the map view using the Window menu options.

Report: File Overview

Click on any of the navigation tabs such as Report, Overview, Overview Map, Radio, CS Domain and PS Domain to explore various pages of the report.

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Report: Overview Map

Maps with Measurements and Failure Events help you to visualize the problem better and to create an appealing report.

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Report: Radio

Statistics and histogram give you a quick overview of the statistics (min, max, average etc.) and the distribution of the EcIo and RSCP analyses.

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Report: CS Domain or PS Domain

CS Call Information drills down to each call and provides call information based on your log file. Call Drops are highlighted in Red while Call Setup Failures are highlighted in Orange. Note that the PS Domain Report looks similar except that only PS call information is displayed.

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Event Explorer The Event Explorer provides a detailed analysis of critical failure events such as

Call Drops and Call Setup Failure. You could arrive at this page from the

Summary Dashboard because of clicking on a Critical Issue or on the Event

Explorer icon. Spotlight contains the following Event Explorer pages for you to

perform a wide range of analyses:

• Circuit Switched

Dropped Calls

Call Setup Failures

Location Update Failures

• Handover Issues

Handover Failures

Missing Neighbors (Only available for Handset and Scanner

data files, using the handset and scanner merge feature)

Information only

• % Strong NBR Diff Baud (better than the serving cell)

• % NBR with 5dB (within 5dB of the serving cell)

• % NBR with 5dB Diff Baud (within 5dB of the serving

cell but different frequency)

The table in the top panel has a row for each site and lists the failure rates for

that site. On the bottom side panel, there is a list of all the dropped calls

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occurring in the drive. If you select a check box in one of the rows, the bottom

side panel will only show the events appearing for the site or sector in that row.

Click on Select Category to select the technology, if you have loaded different technology logfiles.

Click on Event Explorer on the top panel to go to the event dashboard page.

Click on a KPI link to go to the corresponding analysis section.

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View only

View + Drilldown option

You can sort by the Diagnostics column to view the diagnostic types grouped alphabetically.

If the top table shows high values for a particular problem KPI, check the top

left hand box to enable the selection boxes for each row. Then check each row

with high “problem” KPIs. The side panel is now filtered to show the events

appearing for only the selected site or sector rows.

If there are too many rows in the table, you might want to sort by the

Diagnostics column to see the diagnostic types grouped alphabetically.

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Additional Features

You can narrow down your results by choosing which analysis you want to

perform, applying filter, displaying your selected attributes or events you would

like to look at.

Category

Choose a suitable KPI category that you would like to look at quickly to narrow down your result.

Add Filter

Create or Add filter or filters to cut down the outcome and bring you closer to your desire result. You can also delete your filter by clicking on Remove Filter or Remove All.

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Attributes

To help you to understand the problem better, you can visualize more attributes by displaying them on the map. Select the attributes you would like to display on current map from the Attributes drop down list.

Events

You can also view different types of failure events, Pilot Pollution, Too Many Server etc… by selecting them from the Events drop down list. If you’ve loaded other technology logfile, the relevant events will be displayed in the drop down list.

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Detailed Event Diagnostics

The Detailed Event Diagnostics section

provides diagnosis for the failure event.

It consists of the following sections:

Check on the Drill Down checkbox of event that you would like to drill down to.

• Causes

Possible causes for the call drop.

• Further Explanation

Details on the causes for the call

drop

• Further Analysis

Suggestions on how to proceed

with further analysis

• Measurement Information

RF measurements around the

event

In this example, the cause of the

dropped call is due to Handover

Problem. To investigate the problem

further, drill down to a selected

sector(s).

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File-based drilldown: Load the entire file containing the event and analyze further.

Drilldown illdown Until this stage, the analysis has been

based the database. If you would like to

drill down further to message level, click

on Begin Drilldown.

Until this stage, the analysis has been

based the database. If you would like to

drill down further to message level, click

on Begin Drilldown.

The table on the left shows a row for each

Dropped Call event selected for further

drilldown, together with a diagnosis of the

cause.

The table on the left shows a row for each

Dropped Call event selected for further

drilldown, together with a diagnosis of the

cause.

There are a few additional views to help

analyze the event in more detail. A map

and the UMTS Event Navigator window

display attributes relating to the selected

event. There is also a Protocol Stack

Browser providing detailed messaging

around the event.

There are a few additional views to help

analyze the event in more detail. A map

and the UMTS Event Navigator window

display attributes relating to the selected

event. There is also a Protocol Stack

Browser providing detailed messaging

around the event.

Note: All the views will only have data for

the specified time window.

Note: All the views will only have data for

the specified time window.

Time Window drilldown: Specify a time window before and after the event and Actix software will only load data for that window (fastest loading and best time performance).

1. Check on Load entire file if you would like to load the whole file. Note that this will take longer.

2. Key in the desire time in seconds for Before and After box.

3. Check on Load All Devices if you have collected handset and scanner data together, and would like to load all the devices combined.

4. Click on Begin Drilldown to extract detail information (up to message level) from the database.

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Exercise: Drop Call Analysis

In this exercise, we will analyze a call drop where the Dropped Call event will

appear on the map. The cell wedges are colour coded to represent dropped call

numbers. The side panel lists all the critical events occurring in the drive.

We’ll first look at the diagnostics panel on the left or the table in the top panel

where a row for each site lists the failure rates for that site. Note that the table

shows a set of KPIs corresponding to the currently selected Category. This

prevents the table from becoming cluttered by only showing a small set of

related KPIs at the same time.

Investigate this drop call. Confirm if it is due to poor coverage and see if you

can find more information.

Poor EcNo and Good RSSI when call dropped is shown on UMTS Handset State Form. The chart also shows the TxPower, SIR and SIR Target.

This view (screen layout) provides most of the information needed to diagnose a dropped call. It can be modified by saving a new screen layout.

The UMTS Event Navigator State Form shows the event and SC.

Stronger neighbors not selected for handover.

The Protocol Stack Browser provides detailed messaging around the event.

Comment [sf7]: This set of views displayed (Screen Layout) can be modified by the user by saving new screen layout.

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Radio Network Analyses Spotlight contains the following Radio Network Analyses to provide you to

perform wide area coverage based analyses in UMTS:

• Cell Coverage Analysis (based on Scanner/Handset data)

Determines the coverage footprint of cells and identifies overshoot

against coverage design boundaries.

• Missing Neighbors Analysis (3G-3G, 3G-2G)

• Pilot Pollution Analysis (based on Scanner/Handset data)

The UMTS Issues or Important Issues

side panel on the Summary Dashboard

provides a link to each of the above

analysis. Click on a link to go to the

corresponding Radio Network analysis

section, or click on Radio Network Explorer

to go to the corresponding radio network

analysis section.

Click on Radio Network Explorer on the top panel to go to the Radio Network dashboard page.

Click on a link to go to the corresponding Radio Network analysis section.

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Cell Coverage Analyses

The Cell Coverage Analyses allow you to determine coverage for the cells in

their networks. You can use this analysis to:

• Determine the coverage footprint for each cell.

• Visualize where a cell is the best server.

• Visualize where cells are overshooting their coverage design

boundary (defined by SL_Overspill_Dist_Threshold).

These analyses are available for both scanner and handset data.

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Radio Network Explorer Interface

The Radio Network Explorer interface consists of the following components:

Top Panel Summary information is displayed in the top panel. When no rows are selected,

overview information is displayed in the side panel. The top panel includes the

following tabular form information on the sites:

• Scanner

o EcNo, RSCP (Max, Min, Av)

o > Beam – Percentage of points outside the cell beamwidth

o > 180 Beam – Percentage of points outside the 180 Beamwidth

• Handset

o EcNo, RSCP (Max, Min, Av)

o Link Diff. – This is the difference between UL and DL pathloss and is used to highlight cell with possible LNA (TMA) issues. That is if the difference is greater the 8dB

o Downlink Interference factor

o Percentage of coverage issues

• System interference

• Limited coverage

• Poor UL & DL

Note: Clicking on a row in this table causes the side panel to display

more information about the site. The map zooms to the site and displays

the site’s coverage.

Map When a row is clicked in the top panel or a site is clicked on the map, the map

shows the coverage wedge for the selected cell, EcIo and RSCP. The red circle

represents the user-configured coverage design boundary, and data points

outside this circle represent overspill.

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Side Panel This displays various KPI values for the site selected and a histogram of the

distances at which the cell was measured.

for the site selected and a histogram of the

distances at which the cell was measured.

Using the Radio Network Explorer Using the Radio Network Explorer The page operates in two modes: Best Server and Where Seen. Changing the

mode affects the EcIo attribute that is displayed on the map. In Best Server

mode, the EcIo when the selected cell was the best server is displayed. In

Where Seen mode, the EcIo whenever the cell was measured is displayed.

The page operates in two modes: Best Server and Where Seen. Changing the

mode affects the EcIo attribute that is displayed on the map. In Best Server

mode, the EcIo when the selected cell was the best server is displayed. In

Where Seen mode, the EcIo whenever the cell was measured is displayed.

Note: In the where seen mode, the coverage footprint for only the cells that

were best servers in the drive can be visualized.

Note: In the where seen mode, the coverage footprint for only the cells that

were best servers in the drive can be visualized.

Sort all information by clicking on the headings of the top panel’s table.

Cell Coverage This panel displays on the Quality tab various KPI values for the site selected and the Distance tab shows a histogram of the distances at which the cell was measured.

‘Best Server’ and ‘Where Seen’ modes for handset and scanner can be selected from the Analysis drop-down menu.

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Exercise: Cell Coverage Analysis Using Handset Data

The Summary Dashboard shows a Important Issue relating to Poor Coverage.

Hovering over the link shows the thresholds used to identify this issue.

1. Click on the issue link to open the Cell Coverage analysis page.

2. The Issues panel showed a high percentage of System Interference issues,

so examine the top table of the analysis for indications of poorly performing

cells.

This is based on the following Thresholds:

Changing the thresholds value will only take effect after the next load of data.

Several rows have a low sample count and so are unreliable to use in this investigation. To remove rows with low sample counts, apply a filter.

Note that all samples less than 50 are not displayed after the filter is applied.

3. Sort by Average EcIo and color the cells by EcIo by clicking on the icon

beside the column heading.

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4. Examine the map and note that there are some

samples with poor EcIo, despite being very close to

the problem sector.

Note that drive test data is binned according to the

selections made in step 4 of defining the project

template. However, any events displayed on the

map (for example, by using the Events drop-down menu) will use the exact

position rather than a binned position, so events might not align with the

data points.

5. Are any other cells interfering to cause this situation?

Experiment with plotting various Events and Attributes.

Plotting the Uu_ActiveSet_Count attribute shows that there is only one clear server, Site 0433 Sector C. This may indicate a missing neighbor or maybe not.

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6. Click on the 3G Missing Neighbors tab. Note that the map and table keep

the focus on the selected cell.

Seems like there is no recommendation for “Addition” - there is no missing neighbor in this example.

Continue with the next Missing Neighbors exercise to find a good example of a missing neighbor.

Miscellaneous Navigation Concepts

• When moving from a Critical Issue to an Important Issue, all

diagnostic views will be unloaded, except for those opened by the

user - for example: table, Message Browser, Protocol Stack

Browser.

• During your analysis, you may have found it necessary to move or

remove the existing diagnostic views, and to open one or more new

views. To get back to the original layout, select Click here to re-

sync views for this investigation. Note that this will not affect

any views you opened earlier.

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Example: Missing Neighbors Analysis

This analysis lets you groom neighbor lists based on scanner data for sites

within a user-defined radius (Data Settings Maximum Intersite Distance)

of the cell selected. The suggestions made by the software can be exported

directly to a CSV file for easy import and updates directly to the switch.

If the cellrefs file contains neighbor information, the analysis examines the

relationship between the existing neighbors and the potential neighbors as seen

by the scanner, and generates add, remove and retain recommendations for

each site and cell. The interface consists of the following components:

• Top Panel

Summary information is displayed in the top panel. It includes in a

tabular form a number of “addition”, “removal” and “retain”

neighbor recommendations for every site. Clicking on a row in this

table causes neighbor information for the selected cell to be

displayed in the side panel, and lines to neighbors to be drawn on

the map.

• Map

When a row is clicked in the top panel or a site is clicked on the

map, lines to neighbors are drawn from that site. The circle

represents the user-defined radius used by the analysis to identify

potential neighbors. As the data point used in the analysis are

displayed.

• Side Panel

Details of the neighbor recommendations are displayed on the side

panel. Check boxes next to a recommendation can be selected for

export to a CSV file.

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Before You Begin Before you begin, you should have collected the following:

• Scanner data that relates to a single UMTS frequency that is loaded

as a separate stream with a suitable matching cellrefs file.

Increasingly, UMTS scanners are able to scan several frequencies

(identified by the UARFCN) simultaneously.

• This must have been loaded using a suitable matching CellRefs file,

which must contain a field called WCDMANeighborList on the

WCDMA_Cell network element.

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Using Neighbor List Analysis 1. To start this analysis, from the Summary Dashboard page, click on the

Radio Network Explorer button and click on this tab, or click on an

appropriate Important Issue in the left-hand Issues panel.

2. If you have not done so before, check the Data Settings that control the

algorithm for neighbor list analysis. These are the default settings

recommended by Actix (see Appendix B for details).

3. Sort by the Additions column in the top table to find out which

site/sector has the highest number of missing neighbors.

You can now see the sector with the highest number of recommended

additions to its neighbor list.

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4. Click on the top row in the table to show information for that sector.

A Green line indicates the selected sector is recommended to be added, while a red line indicates that the selected sector should be removed.

The thickness of the line indicates the higher percentage, i.e.: Site 0342 sector b1 should be retained (the line is blue) because it has been scanned of total 28.6% and it is a co-sector of sector a1.

The map now shows green lines to each recommended additional neighbor. The

thickness of each line shows how well the suggestion meets the criteria of the

analysis. The circle represents the user-defined radius (Maximum Intersite

Distance) used by the analysis to identify potential neighbors. The map also

displays the data points used in the analysis.

Note that drive test data is binned according to the selections made in step 4 of

defining the project template. However, any events displayed on the map

(for example, by using the Events drop-down menu) will use the exact position

rather than a binned position, so events might not align with the data points.

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5. Examine each suggested additional neighbor.

You may have reasons for refusing to accept the suggestion on

geographical grounds (for example, existing cells between the sector

and the suggested addition), or for reasons related to the data settings.

If you disagree with a suggested addition, you may want to use the SC

Search feature to find an alternative sector to add to the neighbor list.

Note that in this case you will not be able to output your choice, and will

need to make the correction to the switch manually (for example, by

editing the CSV file).

6. If you accept all suggestions for a sector, you can click the related button

in the table to mark your choice.

Note that the number beside the button changes to match your selection.

7. Repeat this process for each row in the top table, as necessary.

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8. You can now go through the same process for the 'Removals' column.

Note that by default the map does not show lines for removal

recommendations.

9. Once you are satisfied with the recommendations that you have selected,

you can output them to a CSV file. From the top of the page, click the

Export Data link.

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Additional Features for 3G Neighbor Analysis



like to look at.

These are some additional features available at this interface:

• Find SC search feature

Visualize an SC on the map where the specified SCs will be colored

red in all the sites. This is very useful to identify the Co-SC

locations quickly.

• Data Settings dialog box

This opens up a dialog box for configuring the algorithm that

Spotlight uses for the UMTS missing neighbor analysis, which can

be used to build lists of suggested neighbor cells to add and

remove. All of the options in the group take effect when you run

the UMTS Missing Neighbor analysis.

• Filters

The table on the top panel can be filtered by adding filters through

this dialog.

• Attributes drop down menu

Lets you plot on the map one or more commonly used attributes.

Currently plotted attributes are shown in red in the list. The

currently selected attributes will be kept as you move between

Spotlight's analysis pages.

• Events drop down menu

As above but for plotting Events on the map.

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Device

Choose the device (handset or scanner) that you would like to look at. In this example, there is only one device “All”, where everything is grouped together.

Find SC Visualize an SC on the map. Specify an SC and this feature colors red all the sites using this SC.

Key in the SC you would like to search for in the Scrambling Code field. Click on Search to search for the SC 273. Note SC 273 is highlighted in RED in the map:

Filter

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Data Settings (See Appendix B for details)

Export Data Select this link to export neighbor recommendations to a CSV file.

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Add Filter


Attributes

To help you to understand the problem better, you can visualize more attributes by displaying them on the map. Select the attributes you would like to display on the current map from the Attributes drop down list.

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Events

You can also view different types of failure events by selecting them from the Events drop down list.

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Exercise: 3G-2G Missing Neighbors Analysis Situations where the 3G network cannot carry a call due to interference or poor radio

conditions - and the call needs to be carried out or completed in the 2G network - are

typically caused by missing neighbors, which are cells that have not been defined in

the neighbor list of the strongest cell at a given location, but which have an RxLevel

good enough to be added to the UE’s neighbor list as a potential cell to hand over from

3G to 2G.

The analysis is a single defined process that integrates map visualization of neighbor

relationships with reported recommendations.

The 3G-2G Missing Neighbors analysis uses scanner data for cells within a specified

radius and compares the visible channels to the current neighbor list as given in the

2G cellrefs data. The results of the analysis are presented in a map and table.

Sort by Additions column to find out the recommendation of which missing neighbor sites/sectors should be added.

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Before You Begin

You will need to have loaded the following:

1. A UMTS scanner stream that relates to a single UMTS frequency.

Increasingly, UMTS scanners are able to scan several frequencies

(identified by the UARFCN) simultaneously.

2. A GSM scanner or handset stream that was logged at the same time. If a

handset stream is used, it must have been logged in idle mode.

3. These must have been loaded using a suitable matching cellrefs file,

which must contain a field called GSMNeighborList on the WCDMA_Cell

network element.

Using Neighbor List Analysis 1. To start this analysis, from the Summary Dashboard page, click on the

Radio Network Explorer button and click on this tab, or click on an

appropriate Important Issue in the left-hand Issues panel:

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2. If you have not done so before, check the data settings that control the

algorithm for neighbor list analysis. In this example, we will be interested

in the Minimum Sample Count and the Addition Threshold. If you alter

a data setting, the analysis will immediately update.

3. Sort the top table by the Additions column. You can now see the sector

with the highest number of recommended additions to its neighbor list.

Check that the Server Count column shows an acceptable value (you can

also define a cutoff threshold using the Minimum Sample Count as shown

above).

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4. Click on the top row in the table to show information for that sector.

Add the CPICH_Scan_EcIo_SortedBy_EcIo_0 attribute to the map.

There are many additions in this example as the cellrefs file does not contain any 3G-2G neighbor definitions - therefore there are also no retentions or removals suggested.

The side panel on the left shows each recommendation for a sector individually, sorted by the % of data points that meet the recommendation algorithm. If you accept the suggestion, you can select the checkbox in the table to mark your choice.

The map now shows lines to the recommended additions. The thickness of each line shows how well the suggestion meets the criteria of the analysis. The circle represents the user-defined radius (Minimum Intersite Distance) used by the analysis to identify potential neighbors. It also displays the data points used in the analysis.

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5. Select and examine a few suggested

additional neighbors. If you accept all

suggestions for a sector, you can select

the related checkbox in the table to

mark your choice.

Note that the number beside the button

changes to match your selection. For

example, there were 178 suggested

additions in the first row, with none

currently selected for export, the

number would show 0/178.

If you clicked, read 178/178. If you do

not want to select every

recommendation for a sector, you can

use the table in the side panel on the

left. So if you selected 13 additions, this

would result in that number - useful if, as in this example, there are many

recommendations, and you need to keep track of how many you have

already selected.

If you refuse to accept the suggestion, for example because there is no

3G-2G neighbor data in the cellrefs file, the sheer number of suggested

additions is 51, compared with the maximum permitted number of 32.

Note that the more potential neighbors you add, the longer it will take a

handset to find appropriate neighbors, conceivably resulting in a dropped

call. You may well have an upper limit already defined by your internal

guidelines.

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6. If you disagree with a suggested addition, you may want to use the View

SC feature to find an alternative sector to add to the neighbor list. Note

that in this case you will not be able to output your choice, and will need

to make the correction to the switch manually (for example, by editing

the CSV file).

7. Repeat this process for each row in the top table, as necessary.

8. You could now go through the same process for the 'Removals' column

(this example contains no 'removals' suggestions). Note that by default

the map does not show lines for removal recommendations.

9. Once you are satisfied with the recommendations that you have selected,

you can output them to a CSV file. From the top of the page, click the

Export data link.

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Example: Pilot Pollution Analysis

This analysis gives you the ability to quickly identify ‘inbound’ vs. ‘outbound’

pilot pollution and visually see the offending sectors on the map. You can

determine the relative degree of pollution for each cell, and prioritize the cells in

the network that are strong candidates for down-tilts and coverage optimization.

This analysis is available for scanner as well as handset data.

Interface The interface consists of the following components:

• Top Panel

Summary information is displayed in the top panel. It includes in a

tabular form the number of pilot pollution events for each site, and

the total number of inbound/outbound polluters. Clicking on a row

in this table causes pilot pollution information for the selected cell

to be displayed in the side panel, and lines to polluters to be drawn

on the map.

Note that you can click on the icon at the left of the table to export

this information in a CSV file.

• Map

When you click a row in the top panel or on a site on the map, lines

to inbound as well as outbound pollution are drawn from that site.

All the pilot pollution events involving the site are also plotted on

the map. The lines to polluters have a direction arrow suggesting

inbound or outbound pollution.

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• Side Panel

Details of the inbound and outbound pollution for the selected site.

All Inbound and Outbound sites and cells (sectors) of the selected sector is listed in the Cell Pilot Pollution Details panel. You can click on the icons on the left to export the related information in a CSV file.

Inbound cells are where the selected sector is being polluted by other sectors. Inbound pilot pollution lines are drawn in blue. Rolling over the lines with the cursor displays more detailed information.

Outbound cells are where the selected sector is polluting other sectors. Outbound pollution lines are drawn in red from the selected sector to the sectors being polluted. The arrow on each line points from the polluting sector to the polluted sector. The thickness of the lines indicates the degree to which pilot pollution was detected for the selected sector, based on the loaded data.

You can choose any of the following Analysis types:

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Additional Features for Pilot Pollution Analysis

These are some additional features available in this interface:

• Filters


this dialog.


This shows commonly used attributes that you can select to plot on

the map.


This shows event attributes that you can select to plot on the map.

So for example, while looking at pilot pollution, you could dump the

UMTS Dropped Call event on the map and quickly find out if the call

dropped due to pilot pollution.

• Analysis drop down

Select Scanner or Handset analysis.

• Overview

Clicking on this link will display an overview of pilot pollution in the

entire drive.

• Find SC

Visualize a SC on the map. Input an SC to visualize on the map,

and this feature would color all the sites with this SC red. This helps

in quickly identifying Co-SC locations.

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Exercise: Pilot Pollution Analysis Using Scanner Data 1. From the Summary Dashboard, click on an appropriate Important Issue in

the left-hand Issues panel, such as Too Many Servers (a pilot pollution

issue). Alternatively, click on the Radio Network Explorer button and click

on the Cell Pilot Pollution tab.

2. Sort by # Outbound Cells

In this example, sector 0433b1 looks like the best candidate for investigation

as it has a high number of Too Many Servers events, and Outbound and

Inbound Cell polluters.

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3. De-select the Inbound Cells box to hide the inbound polluting lines. The

map now highlights the selected sector.

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4. De-select the Outbound and select the Inbound Cells

5. On the map, to show lines to cells, drag a box around the area with a cluster

of Too Many Server events by using the Area Select in the map.

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There is no clear dominator in this area, and a few polluting cells are some

distance away, so you would need to improve the coverage in that area.

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6. In the image below, the EcIo values have been plotted on the map to confirm

the situation near the Too Many Server events.

7. To see how the selected sector is polluting other sectors, from the top table,

de-select Inbound Cells and select Outbound Cells.

8. The selected sector is causing pollution at quite a distance, past much closer

sectors. This confirms that the selected sector may need some downtilt to

avoid causing the pollution and to increase nearby coverage. Use the Cell

Coverage tab to see how best to improve the coverage for the selected

sector.

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Interlude: Using Cellrefs Your trainer will now take you through a separate worksheet on importing,

configuring, modifying and using your own cellrefs files suitable for UMTS. You

will need to have done this before you can proceed to the next section on

examining your own data.

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Workshop: Examining Your Own Data (Optional) This is a freeform section of the course, in which you analyse your own data

samples using Spotlight, with the aid of the course trainer. This is only available

if there is sufficient time, and if prior arrangement has been made with the

course trainer.

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GSM Section

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GSM Summary Dashboard ashboard The Spotlight Summary Dashboard provides you a quick overview of the data





The Spotlight Summary Dashboard provides you a quick overview of the data





Click on Log Files to display all information regarding the data file(s) you’ve loaded.

Click on Event Explorer to drill down to all event-based analyses such as Dropped Calls, Call Setup Failures etc.

Click on Radio Network Explorer to investigate all Radio Network problems and perform wide area coverage-based analyses.

Click on Reports to generate your GSM Spotlight Report based on the configuration and settings you’ve defined. The report consists of some RF parameter charts and maps with important events and attributes.

The Map is an integral part of theSpotlight interface, showing the entire drive, with RxLev being the default attribute plotted. The cell wedges are colour coded: Green represents site that were serving during part of the drive.

The GSM Issues panel lists all critical and important issues occurring in the dataset. It allows you to further investigate and drill down to issues in more detail by clicking on the link of the KPIs. The Critical issues section provides an overview of the drive in terms of failure Events. The Important Issues section includes the Radio Network analyses.

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At the top of the page, the navigation bar allows you to move around in

Spotlight. It also provides some useful functions from any stage of your

analysis:

If your current project uses Global Filters, a related link appears in the

navigation bar. Click on the link to show a dialog similar to this:

This dialog allows you to specify any files or streams that you want to exclude

from the analysis, and also allows you to filter by time (not shown above). Once

you have specified the filter, note that you need to click the Add Filter link on

the right to create the filter. If you have configured regional filtering, this dialog

will also give you the option to filter by region.

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GSM Spotlight Reports Reports are a good place to start when attempting to identify problems in the

loaded data. These can be accessed by clicking on the Reports link from

Spotlight's Summary Dashboard page.

Note: A report must have been activated in the current project's template. It

shows all unfiltered data in the project database for the associated technology.

Click on one of the reports in the navigation tabs, such as Report, File Overview, Overview Map, Radio and CS Domain to explore various pages of the report.

You can either click on the Save button to save the report in .htm format, or click on Show Excel Report button to export the report to Microsoft Excel format.

Note that if you run the report again on different data, the map bitmaps will be updated to reflect the new data. If you subsequently reopen the workbook that was saved earlier, Excel will ask if you want to update. It is important that you choose the Don't Update option, or the maps will be updated with the data from the latest running of the report. The Save button exports the report as a web page. Note that the web page has an associated subfolder with a unique name containing various image and other files relating to that report. However, the image files in each subfolder are always called image1.gif, image2.gif, which may cause you problems in some situations.

To close the Report, click here. To switch views, use the Window menu.

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If you run the report again on different data, the map bitmaps will be updated to

reflect the new data. If you then reopen the workbook that was saved earlier,

Excel asks if you want to update. Choose the Don't Update option, or the maps

will be updated with the data from the latest running of the report.

The Save button exports the report as a web page. Note that the web page has

an associated subfolder with a unique name containing various image and other

files relating to that report. However, the image files in each subfolder are

always called image1.gif, image2.gif, which may cause you problems in some

situations.

To close the report, click on the X on the far right of the application menu

options. If you have a map also open, you can switch between the report and

the map view using the Window menu options.

Report: File Overview

Click on any of the navigation tabs, such as Report, File Overview, Overview Map, Radio and CS Domain to explore various pages of the report.

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Report: Overview Map

Maps with Measurements and Failure Events help you to visualize the problem better and create a more appealing report.

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Report: Radio

Statistics and histograms give you a quick overview of the statistics (min, max, average, etc.) and the distribution of the RxQual and RxLev analysis.

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Report: CS Domain

Call Information drills down to each call and provides call information based on your log file. Call Drops will be highlighted in Red while call setup failure will be highlighted in Orange.

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Event Explorer The Event Explorer provides a detailed analysis of critical failure events such as

Call Drops and Call Setup Failures. You could arrive at this page from the

Summary Dashboard as a result of clicking on a Critical Issue or on the Event

Explorer icon.

Spotlight contains the following Event Explorer pages for you to perform a wide

range of analyses:

• Circuit Switched

Dropped Calls

Call Setup Failures

Location Update Failures

• Handover Issues

Handover Failures

Missing Neighbors (Only available for Handset and Scanner

data files, using the handset and scanner merge feature)

Information only

• % Strong NBR Diff Baud (better than the serving cell)

• % NBR with 5dB (within 5dB of the serving cell)

• % NBR with 5dB diff Baud (within 5dB of the serving

cell but different frequency)

The table in the top panel has a row for each site and lists the failure rates for

that site. On the bottom side panel, there is a list of all the dropped calls

occurring in the drive. If you select a check box in one of the rows, the bottom

side panel will only show the events appearing for the site or sector in that row.

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Click on Event Explorer on the top panel to go to the Event dashboard page.

Click on a KPI link to go to the corresponding event-based analysis section.

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View + Drilldown option

You can sort by the Diagnostics column to see the diagnostic types grouped alphabetically.

View Only

If the top table shows high values for a particular problem KPI, check the top

left hand box to enable the selection boxes for each row. Then check each row

with high problem KPIs. The side panel is now filtered to show the events

appearing for only the selected site or sector rows.

If there are too many rows in the table, you might want to sort by the

Diagnostics column to see the diagnostic types grouped alphabetically.

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Additional Features


perform, applying a filter, or displaying your selected attributes or events you

would like to examine.

Category

Choose a suitable KPI category that you would like to look at quickly, one which reduces the clutter of KPIs in the top table.

Add Filter


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Attributes

To help you to understand the problem better, you can visualize more attributes by displaying them on the map. Select the attributes you would like to display on the current map from the Attributes drop down list.

Events


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Detailed Event Diagnostics

The Detailed Event Diagnostics section

provides diagnosis for the failure event.

It consists of the following sections:

• Causes

Possible causes for the call drop.

See Appendix F for more

information on how the diagnostic

information is derived.

• Further Explanation

Details on the causes for the call

drop

• Further Analysis

Suggestions on how to proceed

with further analysis

• Measurement Information

RF measurements around the

event

In this example, the cause of the

dropped call is due to Poor Coverage.

Further investigate the problem by

drilling down to a selected sector(s).

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Drilldown Up till this stage, the analysis has been

generated from the database. If you

would like to drill down further to

message level, click on Begin

Drilldown to drilldown further.

Check on the Drill Down checkbox of the event that you would like to drill down to.

File-based drilldown: Load the entire file containing the event and analyze further.

Time Window drilldown: Specify a time window before and after the event and Actix software will only load data for that window (fastest loading and best time performance).

1. Check on Load entire file if you would like to Load the whole file. Note that this will take longer time.

2. Key in the desire time in seconds for Before and After box.

3. Check on Load All Devices if you have collected handset and scanner data together, and would like to load all the devices combined.

4. Click on Begin Drilldown to extract detail information (up to message level) from the repository (database).

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Exercise: Drop Call Analysis

In this exercise, we will analyze a call drop where the dropped call event will

appear on the map. The cell wedges are color coded to represent dropped call

numbers. The side panel lists all the critical events occurring in the drive.

We’ll first look at the diagnostics panel on the left or table in the top panel

where it has a row for each site and lists the failure rates for that site. Note that

the table shows a set of KPIs that correspond to the current Category to

prevent the table from becoming cluttered by only showing a small set of related

KPIs at the same time.

Investigate this drop call. Confirm if it is due to poor coverage and see you can

find more information.

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Poor RxLev and poor Quality when call dropped is shown on GSM Line Chart State Form. The chart also shows the RxLev, Rx Qual and UE TxPower.

This view (screen layout) provides most of the information needed to diagnose a dropped call. It can be modified by saving a new screen layout.

Handover Failure right before the call dropped is shown on GSM Troubleshooter Navigator State Form. It shows the event and serving BCCH.

Stronger neighbor not selected for handover.

Protocol Stack Browser provides detail messaging around the event. Note that there was a Handover Failure before the drop.

Comment [sf8]: This set of views displayed (Screen Layout) can be modified by the user by saving new screen layout.

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Radio Network Analyses Spotlight contains the following Radio Network Analysis:

• Coverage and Overspill Analysis (based on Handset and

Scanner data)

Allows you to perform wide area coverage-based analyses in GSM;

it determines the coverage footprint of cells and identifies

overshoot against coverage design boundaries. The GSM Issues or

Important Issues side panel on the Summary Dashboard

provides a link to this analysis. Alternatively, click on Radio

Network Explorer.

Click on a link to go to the corresponding Radio Network analysis section.

Click on Radio Network Explorer on the top panel to go to the Radio Network dashboard page.

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Cell Coverage Analysis

The Cell Coverage Analysis allows you to determine coverage for the cells in

their networks. Using either scanner or handset data, you can use this analysis

to:

• Determine the coverage footprint for each cell.

• Visualize where a cell is the best server.

• Visualize where cells are overshooting their coverage design

boundary (defined by SC_Overspill_Dist_threshold).

• Visualize the neighbor, BCCH and TCH plans.

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Radio Network Explorer Interface

This consists of the following components:

Top Panel

Summary information is displayed in the top panel. When no rows are

selected, overview information is displayed in the side panel. It includes in

tabular form information on the sites, containing the following information:

• BCCH

• # - Number of samples. Ensure that you are looking at a statistically sensible number of samples.

• > Dist. - Number of samples greater than the coverage design boundary (defined by SL_Overspill_Dist_Threshold).

• RxQual, RxLev, (Av, Max, Min). Note that clicking on the icon only displays the Average value.

• % > Beam – Percentage of points outside the cell beamwidth.

• % >180 Beam – Percentage of points outside a hypothetical beamwidth of 180 degrees.

• Link Diff – This is the difference between UL and DL pathloss and is used to highlight cell with possible LNA (TMA) issues, if the difference is greater the 8 dB, where: UL = UE Tx Power - BTS Sensitivity + BTS Antenna Gain DL = BTS EIRP - RxLevSub

• Poor Ql % and Poor Lv % combined with No Dom % (see Coverage Criteria in page 103 for details).

Note: Clicking on a row in this table causes the side panel to display

more information about the site. The map zooms to the site and displays

its coverage.

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Map When a row is clicked in the top panel or a site is clicked on the map, the map

shows the coverage wedge for the selected cell, RxLev (and RxQual for best

server only). The red circle represents the user-configured coverage design

boundary, and data points outside this circle represent overspill.

Side Panel This displays various KPI values for the site selected and a histogram of the

distances at which the cell was measured (see the next section for examples).

Using the Radio Network Explorer The page operates in two modes: Best Server and Where Seen. Changing the

mode affects the RxLev attribute that is displayed on the map. In Best Server

mode the RxLev when the selected cell was the best server is displayed (note

that in this mode, RxQual can be seen). In Where Seen mode, the RxLev

whenever the cell was measured is displayed.

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Note: In the where seen mode, coverage footprint for only the cells that were

best servers in the drive can be visualized.

Sort all information by clicking on the headings of the top panel’s table.

Best Server and Where Seen mode can be selected from the Analysis drop down menu.

In this example, the Quality tab of the side panel shows a percentage of Poor RxQual at the same time as Good RxLev, which usually indicates interference.

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The Distance tab shows the distance at which the cell was measured:

The Visualization tab highlights co/adjacent channel information on the map:

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Clicking on a binned data point on the map displays extra Information:

You can also use the Area Select button to drag a box around all binned data

points for which you want to display Info:

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Additional Features

These are some additional features available at this interface:

• Filters


this dialog.


Select one or more commonly used attributes to plot on the map


Select one or more events to plot on the map

• Analysis drop down menu

Select handset (Best Server or Where Seen)

• Show Overview

Clicking on this link will display an overview of Grade of Service for

the entire drive.



like to look at.

Device

Choose the device (handset or scanner) that you would like to look at. In this example, there is only one device “All”, where everything is grouped together.

Analysis

Where Seen is where the map will show a different footprint of the sector, where it was detected anywhere during the drive, not just the strongest signal. Note: The coverage footprint for only the cells that were best servers in the drive can be visualized. Best Server is by selecting the row will select the cell on the map will show the areas on the map where the selected cell has been detected as the strongest cell.

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Add Filter


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Attributes

To help you understand the problem better, you can visualize more attributes by displaying them on the map. Select the attributes you would like to display on the current map from the Attributes drop down list.

Events


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Miscellaneous Navigation Concepts • When moving from a Critical Issue to an Important Issue, all

diagnostic views will be unloaded, except for those opened by the

user - for example: tables, Message Browser, Protocol Stack

Browser.

• During your analysis, you may have found it necessary to move or

remove the existing diagnostic views and to open one or more new

views. To get back to the original layout, select Click here to re-

sync views for this investigation. Note that this will not affect

any views you opened earlier.

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Exercise: No Dominance

The Summary Dashboard shows a Important Issue: '% area with No Serving

Cell Dominance' (See Coverage Criteria on page 103 for details)

Click on the no Serving Cell Dominance link to open the Cell Coverage analysis page.

1. Click on the issue link to open the Cell Coverage analysis page.

2. Note that several rows in the top table have a low sample count, '#', and

so are unreliable to use in this investigation.

3. To remove rows with low sample counts, apply a Filter with a threshold

of, say, 50 counts. Click Add Filter and OK.

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4. From the Attribute drop-down menu, select an attribute to plot on the

map, based on the related Important Issue from the Summary Dashboard

(for this example, No Serving Cell Dominance):

Important Issue Attribute

Poor Voice Quality ServRxQualSub

Poor Signal Strength ServRxLevSub

The attribute is used in the calculation to identify the issue, as explained

in Coverage Criteria on page 103.

Note: The drive test data is binned according to the selections made in

defining the project template earlier. However, any events displayed on

the map (for example, by using the Events drop-down menu) will use the

exact position rather than a binned position, so events might not align

with the data points.

5. Examine the top panel summary information, which provides indications

of poorly performing cells relating to the Important Issue, and select likely

candidate rows.

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In the example below, a problem row has been selected. The first map image

shows the 'NumNeighbors within 5 dB' attribute, which highlights an area of

poor dominance (drawn in red). The second map image shows RxLev (Where

Seen) plotted for the same sector, which shows that it covers an unnecessarily

large area. This could be corrected by applying some downtilt to the sector.

Coverage Criteria

Condition Top table column or Quality tab1

Criteria

Poor Voice Quality

Poor Quality, Poor Ql

ServRxQualSub < G_RxQualSub_Max threshold

Poor Signal Strength

Poor Level, Poor Lv

ServRxLevSub < G_RxLevSub_Min threshold

No Serving Cell Dominance

No Dom If the sum of all these conditions is > 2: ((ServRxLevSub-NborRxLev[n])<5) * (abs(ServBCCH-NborBCCH[n])<375), where n is 0 to 5.

Good Design G. Design % Where none of the above conditions is true.

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Exercise: GSM Visualization

This analysis is used to highlight and investigate interference issues within the

cell coverage page, where you can look at all the Co-Adjacent interfering cells.

In this exercise, you will select one or two sectors with different analysis radii

(change G_Interference_Radius thresholds value) to check out the BCCH

Co/adjacent Channel or the TCH Co/adjacent Channel. Please see

Appendix G on how BCCH and TCH Adjacent Cells are defined.

1 This is the percentage of data points where one (or more than one) condition applies.

1. Sort by % RxQual

2. Select a sector with good RxLev and poor RxQual (Inteference). Click on the sector to zoom in to that area.

By clicking on Distance tab, the Distance Chart will display a histogram of the distances at which the cell was measured:

Quality tab shows the percentage of Good and Poor RxQual and RxLev in the data.

By clicking on Visualization tab, the Distance Chart will be displayed:

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Orange color is for upper adjacent channel interference.

The red circle in the map displays the maximum range for the analysis, as defined in Tools Thresholds Spotlight SL_Overspill_Dist_threshold.

Yellow color is for lower adjacent channel interference/

Red color is for co-adjacent channel interference.

You can set your G_Interference_Radius threshold at Tools Display Thresholds GSM Cell_Plan_Viewer as below:

And set the threshold unit either in KM or Miles at Tools Preferences General Settings Distance Units

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Interlude: Using Cellrefs Your trainer will now take you through a separate worksheet on importing,

configuring, modifying and using your own cellrefs files suitable for GSM. You

will need to have done this before you can proceed to the next section on

examining your own data.

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Workshop: Examining Your Own Data (Optional) This is a freeform section of the course in which you analyse your own data

samples using Spotlight, with the aid of the course trainer. This is only available

if there is sufficient time, and if prior arrangement has been made with the

course trainer.

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Appendix A: UMTS Thresholds You can modify threshold values for event detection using the Tools, Display

Thresholds command. It is important to set your threshold before loading the

data because it will affect the analysis, diagnosis and display of data in

Spotlight. To modify the value, simply click on the associated number and type

in the new value.

Spotlight

SL_Overspill_Dist_Threshold This threshold is used, if there is no Max_ServerDist information in the cellref

and indicates the maximum serving distance (in meters) a cell should serve.

Default is 5000m.

UMTS / Scan_coverage

Uu_Scan_PilotPollutionThreshold In calculating Pilot Pollution, this threshold sets up the level of interference

required for pegging the events (based on scanner info). When 4 or more pilots

are above this threshold, it creates a pilot pollution event. Recommended value

is -15dB and the minimum and the maximum should be around -18 and -10 dB.

Uu_Scan_Poor_EcNoThreshold This is used to indicate poor EcIo values from scanner data. Recommended

value is -15 dB and should lie between -18 and -10 dB.

Uu_Scan_Poor_RSCP_Threshold This is used to indicate poor RSCP values from scanner data. Recommended

value is -95 dBm and should not be lower than -105 dBm.

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Uu_Scan_TooManyServersThreshold In calculating "Too Many Servers", when 4 or more pilots (including the best

server) are within the threshold value in dB of the best server, it creates a "too

many server" event (based on scanner info). Recommended value is 5 dB and

the minimum and the maximum should be around 1 and 10 dB.

UMTS / Spotlight

SL_Ant_Gain_Threshold This threshold is the default Antenna gain, used in the calculation of pathloss.

The default value is 18.4 dB.

SL_BLER_Threshold This threshold is used for determining a UMTS ‘lost DL channel’ condition. The

default value is 10 dB.

SL_BTS_Sens_Threshold This threshold is the default BTS receive Sensitivity, used in the calculation of UL

pathloss. The default value is -120 dBm.

SL_Detectedset_EcIo_Threshold This threshold is used for determining if a detected set member strong enough

to be consider as a neighbor. The default value is -15 dB.

SL_EIRP_Threshold This threshold is the default EIRP, used in the calculation of DL pathloss. The

default value is 50.

SL_MaxTimeBetweenRRC_REQandCallStart This threshold is used for determining UMTS CS calls with excessive setup time.

Recommended value is 6000 ms.

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SL_RapidPathloss_EcIo_Threshold This threshold is used in Rapid Pathloss detection, a condition of which is that

EcIo has dropped by at least this threshold value within the defined time

window. The RSCP condition must also be met for Rapid Pathloss to be detected.

The default value is 5 dB.

SL_RapidPathloss_RSCP_Threshold This threshold is used in Rapid Pathloss detection, a condition of which is that

RSCP has dropped by at least this threshold value within the defined time

window. The EcIo condition must also be met for Rapid Pathloss to be detected.

The default value is 5.

SL_RapidPathloss_Time_window_Threshold This threshold is used to define the window over which Rapid Pathloss is

performed. The default value is 3000 ms.

SL_Site_Issues_Dist_Threshold This threshold is used in the outside beamwidth analysis, and only data within

this distance from the site is considered for the analysis. The default value is

5000m.

SL_UMTS_DT_Troubleshooter_CriticalIssues_Threshold This threshold is used to filter out critical issues from the UMTS dashboard that

are equal or less then this value. Recommended value is 0.

SL_UMTS_DT_Troubleshooter_ImportantIssues_Threshold This threshold is used to filter out Important issues from the UMTS dashboard

that are equal or less then this value. Recommended value is 0.

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UMTS / UE_Coverage

Uu_CoverageLimitedUE_TxPowerThreshold This is used in the Coverage Limited event. If the UeTransmittedPower is greater

than Uu_CoverageLimitedUE_TxPowerThreshold AND the

CPICH_RSCP_in_ActiveSet is less than Uu_Poor_RSCP_Threshold AND the

CPICH_EcNo_in_ActiveSet is less than Uu_Poor_EcNoThreshold, then a

Coverage Limited event will appear on the map. Recommended value is 10 dBm.

The minimum should not be lower than 0 and the maximum should not be

higher than 25 dBm.

Uu_EcNoInterferenceThreshold This is used in conjunction with the RSCP Interference Threshold for the System

Interference event. If the CPICH_RSCP_in_ActiveSet is greater than

Uu_RSCP_Interference_Threshold and the CPICH_EcNo_In_ActiveSet is less

than Uu_EcNoInterferenceThreshold, then a System Interference event appears

on the map. Recommended value is -15 dB. Values should lie between -10 and -

18 dBm.

Uu_HighUE_TxPower This is used in the Poor Uplink Coverage event. If the UeTransmittedPower is

greater than Uu_HighUE_TxPower AND the CPICH_RSCP_in_ActiveSet is greater

than Uu_Poor_RSCP_Threshold AND the CPICH_EcNo_in_ActiveSet is greater

than Uu_Poor_EcNoThreshold, then Poor Uplink Coverage will appear on the

map. Recommended value is 15 dBm. Values should lie between 0 and 25 dBm.

Uu_LowUE_TxPower This is used in the Poor Downlink Coverage event. If the UeTransmittedPower is

less than Uu_LowUE_TxPower AND the CPICH_RSCP_in_ActiveSet is less than

Uu_Poor_RSCP_Threshold AND the CPICH_EcNo_in_ActiveSet is less than

Uu_PoorEcNoThreshold, then the Poor Downlink Coverage event will appear on

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the map. Recommended value is -15 dBm. Values should lie between -30 and 0

dBm.

Uu_PilotPollutionThreshold In calculating Pilot Pollution, this threshold sets up the level of interference

required for pegging the events. When 4 or more pilots are above this threshold,

it creates a Pilot Pollution event. Recommended value is -15 dB and should lie

between -18 and -10 dB.

Uu_Poor_EcNoThreshold This is used in the Coverage Limited event. If the CPICH_EcNo_in_ActiveSet is

less than Uu_PoorEcNOThreshold AND CPICH_RSCP_in_ActiveSet is less than

Uu_Poor_RSCP_Threshold AND Ue_TransmittedPower is greater than

Uu_CoverageLimitedUE_TxPowerThreshold, then a Coverage Limited event will

appear on the map. It is also used in the Poor Uplink and Downlink Coverage

event. Recommended value is -15 dB and should lie between -18 and -10 dB.

Uu_Poor_RSCP_Threshold This is used in three different events. In the cases where

CPICH_RSCP_in_ActiveSet is lower than Uu_Poor_RSCP_Threshold, it will trigger

either a Coverage Limited event or a Poor Downlink Coverage event. In the case

where it is greater than Uu_Poor_RSCP_Threshold, it will trigger a Poor Uplink

Coverage event. Other conditions must be satisfied for these events to occur -

please note the other thresholds involved.

Recommended value is -95 dBm and should not be lower than -105 dBm.

Uu_RSCP_InterferenceThreshold This is used for the System Interference event. If the CPICH_RSCP_in_ActiveSet

is greater than this threshold and the CPICH_EcNo_in_ActiveSet is less than

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Uu_Poor_EcNoThreshold, then a System Interference event appears on the map.

Recommended value is -80 dBm and should lie between -90 and -60 dBm.

Uu_TooManyServersThreshold In calculating "Too Many Servers", when 4 or more pilots (including the best

server) are within the threshold value in dB of the best server, it creates a "too

many server" event (based on scanner info). Recommended value is 5 dB and

the minimum and the maximum should be around 1 and 10 dB.

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Appendix B: Data settings for UMTS Neighbor

Analyses

Setting Default value

Description

Reporting Range (dB)

5 For each data point, the algorithm creates a candidate list that includes those SCs within the Reporting Range value of the strongest signal. For example, if the strongest signal is -4 dBm, the default value of 5 dB would include in the candidate list all weaker SCs with signal strengths down to -9 dBm.

Addition Threshold (%)

1 Defines the percentage of samples that must be reached to trigger a cell being added as a suggested neighbor. This is used to reduce the effect of stray signals.

Removal Threshold (%)

0.2 Defines the minimum percentage of samples that cells in the current neighbor list must achieve in order to be recommended for retention in the list. When the percentages of samples fall below this threshold, cells will be recommended for removal from the list.

Minimum Samples

50 Only sectors which have been measured above the Ec/Io Threshold at least this many times will be included in the analysis. Note that the algorithm works off Binned data.

UMTS Threshold Type

Used for 3G-2G Neighbor Analysis. Depending on which measurement your network uses for determining when to hand over, select EcIo, RSCP, EcIo or RSCP, or EcIo and RSCP.

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Description

Maximum Intersite Distance (meters)

5000 Defines the maximum line-of-sight distance in meters between two cells for one to be considered for inclusion on the other's neighbor list. For rural areas where the average intersite distance is naturally greater than a dense urban environment, use a higher value. To disable this feature, set this value to 0.

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Setting Default Description value

Angle to site threshold (degrees)

90

Defines the maximum angle between the edge of a cell's beam width and the data point, for that cell to be considered for inclusion in the serving cell's neighbor list.

In this example, the beam width is shown as a darker blue arc, and the angle to site threshold in lighter blue arcs on either side. Acceptable data points are within this threshold of the candidate sector's beam width, and are also within the Maximum Intersite Distance (the blue circle).

This threshold ensures that missing neighbors are not suggested from reflected signals or back-lobes, and also that only cells angled towards the data point are suggested.

To disable this feature, set this value to 0.

Only process first best SC

Selected

Select this option to analyze the neighbors of the best cell only. De-select this option if you want to analyze the neighbor list of all of the cells within the reporting range.

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Description

Maximum Size 15 Defines the maximum number of candidates in the candidate list.

Include existing neighbors

Selected

Used for 3G Neighbor Analysis. Select this option for the current neighbor list in the cellrefs file to be considered for additions and removals.

EcIo Threshold (dB)

0 Used for 3G-2G Neighbor Analysis. A neighboring cell must have an EcIo of less than or equal to this value to be included on the potential neighbor list.

RSCP Threshold (dBm)

-100 Used for 3G-2G Neighbor Analysis. A neighboring cell must have an RSCP of less than or equal to this value to be included on the potential neighbor list.

Once a potential neighbor list has been calculated for each data point, they are

aggregated by serving cell to produce the recommended neighbor list. This is

compared with the existing list to calculate which are additions, retentions and

removals.

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Appendix C: UMTS Event Diagnoses

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Dropped Calls

Diagnosis Condition and notes

System Released When the cause code is Not Normal (0-31, 42) in either

the NAS message or the RRC message.

Missing Neighbor SC in Active Set after event < > SCs in Active Set and

Neighbor list before event.

Handover Problem Multiple Active Set update messages are received and a

particular SC is not added to the Active Set.

For the Raked RF Condition, the system picks the diagnosis with the highest

value, providing it is higher than the specified threshold:

Pilot Pollution 4+ pilots in Active or Monitored Set with

Ec/No > Uu_PilotPollutionThreshold (-15 dB).

Pilot Pollution:

Too Many Servers

4+ pilots in the Active or Monitored Set with Ec/No within

Uu_TooManyServersThreshold dB of the best server

(Uu_ActiveSet_EcNo_0).

Interference Problem CPICH_EcNo_in_ActiveSet <

Uu_EcNoInterferenceThreshold (-15 dB) AND

CPICH_RSCP_in_ActiveSet >

Uu_RSCP_InterferenceThreshold (-80 dBm).

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Dropped Calls


Coverage Limitation

Problem

CPICH_EcNo_in_ActiveSet < Uu_Poor_EcNoThreshold (-

15 dB) AND

CPICH_RSCP_in_ActiveSet < Uu_Poor_RSCP_Threshold

(-95 dBm) AND

UeTransmittedPower >

Uu_CoverageLimitedUE_TxPowerThreshold (10 dBm).

Poor DL Coverage

Problem

CPICH_EcNo_in_ActiveSet < Uu_PoorEcNoThreshold (-15

dB) AND


(-95 dBm) AND

UeTransmittedPower < Uu_LowUE_TxPower (-15 dBm).

Poor UL Coverage

Problem

CPICH_EcNo_in_ActiveSet > Uu_Poor_EcNoThreshold (-

15 dB) AND

CPICH_RSCP_in_ActiveSet > Uu_Poor_RSCP_Threshold

(-95 dBm) AND

UeTransmittedPower > Uu_HighUE_TxPower (15 dBm).

Lost DL Channel Over 5-seconds, on average, Uu_Trch_DownlinkBLERAGG

> SL_BLER_Threshold.

Investigate Further

(unknown diagnosis)

More investigation is needed. Use other tools and views

to refine your understanding of the problem.

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Note that the window size used to evaluate the condition is the period from 5

seconds before the drop, up to the drop itself.

Call Setup Failure


System Rejected /

RRC Failure

When an RRC message contains an RRC Reject.

CM Service

Abort/Reject

A CM Service Abort / Reject message was received.


the NAS message or the RRC message.

Missing Neighbor SC in Active Set after event < > SCs in Active Set and

Neighbor list before event.

Handover Problem Multiple Active Set update messages are received and a

particular SC is not added to the Active Set.

For the Raked RF Condition, the system picks the diagnosis with the highest

value, providing it is higher than the specified threshold:


Ec/No > Uu_PilotPollutionThreshold (-15 dB).

Pilot Pollution:

Too Many Servers

4+ pilots in the Active or Monitored Set with Ec/No within

Uu_TooManyServersThreshold dB of the best server

(Uu_ActiveSet_EcNo_0).

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Call Setup Failure





Uu_RSCP_InterferenceThreshold (-80 dBm).

Limited Coverage

Problem


15 dB) AND


(-95 dBm) AND


Uu_CoverageLimitedUE_TxPowerThreshold (10 dBm).

Poor DL Coverage

Problem

CPICH_EcNo_in_ActiveSet < Uu_PoorEcNoThreshold (-15

dB) AND


(-95 dBm) AND

UeTransmittedPower < Uu_LowUE_TxPower (-15 dBm).

Poor UL Coverage

Problem


15 dB) AND


(-95 dBm) AND

UeTransmittedPower > Uu_HighUE_TxPower (15 dBm).

Lost DL Channel Over 5-seconds, on average, Uu_Trch_DownlinkBLERAGG

> SL_BLER_Threshold.

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Call Setup Failure


Investigate Further

(unknown diagnosis)

Use other tools and views to refine your understanding of

the problem.

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Note that the window size used to evaluate the condition is the period from 5

seconds before the drop, up to the drop itself.

Excessive Calls


Multiple RRC attempts More than 1 RRC attempt.

For the Coverage Issue Condition, the system picks the diagnosis with the

highest value, providing it is higher than the specified threshold:


Ec/No > Uu_PilotPollutionThreshold (-15 dB)




Uu_RSCP_InterferenceThreshold (-80 dBm)

Limited Coverage

Problem


15 dB) AND


(-95 dBm) AND


Uu_CoverageLimitedUE_TxPowerThreshold (10 dBm)

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Excessive Calls


Poor DL Coverage

Problem


15 dB) AND


(-95 dBm) AND


Uu_CoverageLimitedUE_TxPowerThreshold (10 dBm)

Poor UL Coverage

Problem


15 dB) AND


(-95 dBm) AND

UeTransmittedPower > Uu_HighUE_TxPower (15 dBm)

High RAB Activation

Time

Uu_RRC_RadioBearerSetup_r3_IEs_activationTime_0 >

229

(part of the RadioBearerSetup message)

Investigate Further

(unknown diagnosis)

More investigation needed. Use other tools and views to

refine your understanding of the problem.

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Appendix D: GSM Thresholds You can modify threshold values for event detection using the Tools, Display

Thresholds command. It is important to set your threshold before loading the

data because it will affect the analysis, diagnosis and display of data in

Spotlight. To modify the value, simply click on the associated number and type

in the new value.

Spotlight

SL_Overspill_Dist_Threshold This threshold is used if there is no Max_ServerDist information in the cellref

file, and indicates the maximum serving distance (in meters) a cell should serve.

Default is 5000m.

GSM / Advanced_Handover_Analysis

Dragged_Dominance_Hysteresis This threshold is the dBm hysteresis applied to the Best Neighbor Level to

trigger a loss of dominance of the server. Once a loss of dominance is triggered,

and not re-established before the Dragged_HO_Window timer expires, then any

subsequent Handover Failure or Dropped Call will trigger the Dragged Handover

Failure or Dragged Drop. Dominance loss = ServRxLevSub < (Best_Nbr -

Hysteresis). The default value is 5 dBm.

Dragged_HO_Window This threshold is the number of milliseconds that the MS must lose dominance

for, before a Dragged Handover Failure or Dragged Dropped Call is triggered.

The default value is 10000 ms.

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Ping_Pong_HO_Window This threshold is the number of milliseconds during which a handover back to

the previous cell will trigger the Ping Pong Handover Event. The default value is

6000 ms.

GSM / Analysis

G_Distance_Max This threshold is used to determine the maximum distance allowed per cell.

Typically, values in excess of 8000 meters are usually regarded as distant

serving cells.

G_Handover_Min This threshold is used in conjunction with handover to determine the minimum

possible signal difference for handover to take place. Recommended values are

5-6 dB.

G_MsTxPowStepOrdered_Min This threshold is used in conjunction with the signal strength to determine

incorrect uplink power balance. This value is usually set to 0 to indicate

maximum uplink power.

G_Prolong_Interf_timer This threshold is used in conjunction with the signal strength and signal quality

to determine prolong interference – that is, good signal strength but bad quality

in this time window will cause a prolong interference event.

G_RxLevSub_Min This threshold is used to determine the minimum acceptable value for signal

strength. Any signal below this threshold is categorized as poor coverage.

Recommended value: -95 dBm.

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G_RxQualSub_Max This threshold is used in conjunction with the signal strength to determine

whether there is interference present on the cell. Typically, values in excess of 3

with good signal strength usually indicate the presence of interference.

G_TimingAdvance_Max This threshold is used in absence of the Distance parameter to determine the

maximum distance allowed per cell. Typically, values over 16 (that is,

approximately 8 km) are usually regarded as distant serving cells.

GSM / Cell_Plan_Viewer

G_Interference_Radius This value is used to define a radius of analysis about a selected sector for co-

adjacent interference and neighbors visualizations in the Cell Plan Viewer. You

can set the units to be used (either miles or kilometers) in Preferences, General

Settings, Distance Units.

G_ScanSortSigLevel_Min This value is used in relation to the scanner signal level; for example, in the

Channel Overlap analysis in the GSM Cell Plan Viewer.

GSM / Events

G_Timeout_ChannelRequest This value is used to determine the time (in ms) the system will wait for RR

Channel Request messages to be answered before registering a Call Setup

Failure. Default is 3000 ms.

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GSM / Spotlight

SL_GSM_Ant_Gain_Threshold This threshold is the default Antenna gain, used in the calculation of pathloss.

The default value is 18.4 dB.

SL_GSM_BTS_Sens_Threshold This threshold is the default BTS receive sensitivity, used in the calculation of UL

pathloss. The default value is -120 dBm.

SL_GSM_EIRP_Threshold This threshold is the default EIRP, used in the calculation of DL pathloss. The

default value is 55.

SL_GSM_High_TX_Power_Threshold This threshold is used for determining a ‘High TX’ condition. The default value is

30.

SL_GSM_RapidPathloss_RxLev_Threshold This threshold is used in Rapid Pathloss detection, a condition of which is that

RxLev has dropped by at least this threshold value within the defined time

window. The RxQual condition must also be met for Rapid Pathloss to be

detected. The default value is 5 dB.

SL_GSM_RapidPathloss_RxQual_Threshold This threshold is used in Rapid Pathloss detection, a condition of which is that

RxQual has dropped by at least this threshold value within the defined time

window. The RxLev condition must also be met for Rapid Pathloss to be

detected. The default value is 2.

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SL_GSM_RapidPathloss_Time_window_Threshold This threshold is used to define the window over which Rapid Pathloss is

performed. The default value is 3000 ms.

SL_GSM_Site_Issues_Dist_Threshold This threshold is used in the ‘outside beamwidth’ analysis, and only data within

this distance from the site is considered for the analysis. The default value is

5000m.

GSM / Troubleshooter

G_Analysis_Time_After This value is used to determine the time (in ms) allocated to investigate the

radio conditions AFTER the detected event occurrence. Typically, values of 5000

to 10000 ms are used. Values less than 5000 ms will tend to be more accurate,

but less attributes will be detected, while values in excess of 10000 ms tend to

have a high detection of attributes, but with relatively low accuracy since the

time under analysis is large.

G_Analysis_Time_Before This value is used to determine the time (in ms) allocated to investigate the

radio conditions PRIOR to the detected event occurrence. Typically, values of

5000 to 10000 ms are used. Values less than 5000 ms will tend to be more

accurate, but fewer attributes will be detected, while values in excess of 10000

ms tend to detect a large number of attributes, but with relatively low accuracy

since the time under analysis is large.

G_CallDropRate This threshold is used to determine the criterion for KPI acceptance in the

repository views. The Call Drop Rate should not exceed 2% of all successful calls

in the busy hour. If the resulting KPI is equal to or less than this value, it will be

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flagged as accepted and will show up as a green tick mark in the KPI table. If it

is higher than this value, it will be flagged as failed and will show up as a red

cross in the KPI table.

G_CallSetupSuccessRate This threshold is used to determine the criterion for KPI acceptance in the

repository views. The Call Setup Success Rate should be in excess of 98% for

most GSM networks in the busy hour. If the resulting KPI is equal to or in excess

of this value, it will be flagged as accepted and will show up as a green tick

mark in the KPI table. If it is less than this value, it will be flagged as failed and

will show up as a red cross in the KPI table.

G_HandoverSuccessRate This threshold is used to determine the criterion for KPI acceptance in the

repository views. The Handover Success Rate should be in excess of 98% for

most GSM networks in the busy hour. If the resulting KPI is equal or in excess to

this value, it will be flagged as accepted and will show up as a green tick mark in

the KPI table. If it is less than this value, it will be flagged as failed and will

show up as a red cross in the KPI table.

G_LocationUpdateSuccessRate This threshold is used to determine the criterion for KPI acceptance in the

repository views. The Location Update Success Rate should be in excess of 98%

for most GSM networks in the busy hour. If the resulting KPI is equal or in

excess to this value, it will be flagged as accepted and will show up as a green

tick mark in the KPI table. If it is less than this value, it will be flagged as failed

and will show up as a red cross in the KPI table.

G_OverAllSuccessRate This threshold is used to determine the criterion for KPI acceptance in the

repository views. The Overall Success Rate should be in excess of 98% for most

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GSM networks in the busy hour. If the resulting KPI is equal or in excess to this

value, it will be flagged as accepted and will show up as a green tick mark in the

KPI table. If it is less than this value, it will be flagged as failed and will show up

as a red cross in the KPI table.

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Appendix E: Data settings for GSM 2G Neighbor

Analysis


Description

RxLev Threshold (dBm)

-95 The RxLev of the serving cell must be better than this value before the cell will be considered in the analysis.

Reporting Range (dB)

5 The RxLev of the serving cell must be no further than this from the RxLev Threshold before the cell will be considered in the analysis.

Addition Threshold (%)

1 Defines the percentage of samples that must be reached to trigger a cell being added as a suggested neighbor. This is used to reduce the effect of stray signals.

Removal Threshold (%)

0.2 Defines the minimum percentage of samples that cells in the current neighbor list must achieve in order to be recommended for retention in the list. When the percentages of samples fall below this threshold, cells will be recommended for removal from the list.

Minimum Samples

50 Only sectors which have been measured above the Ec/Io Threshold at least this many times will be included in the analysis. Note that the algorithm works off Binned data.

Maximum Intersite Distance (meters)

5000 Defines the maximum line-of-sight distance in meters between two cells for one to be considered for inclusion on the other's neighbor list. For rural areas where the average intersite distance is naturally greater than a dense urban environment, use a higher value. To disable this feature, set this value to 0.

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Setting Default Description value

Angle to site threshold (degrees)

90

Defines the maximum angle between the edge of a cell's beam width and the data point, for that cell to be considered for inclusion in the serving cell's neighbor list.

In this example, the beam width is shown as a darker blue arc, and the angle to site threshold in lighter blue arcs on either side. Acceptable data points are within this threshold of the candidate sector's beam width, and are also within the Maximum Intersite Distance (the blue circle).

This threshold ensures that missing neighbors are not suggested from reflected signals or back-lobes, and also that only cells angled towards the data point are suggested.

To disable this feature, set this value to 0.

Only process first best ARFCN

Selected Select this option to analyze the neighbors of the best cell only. De-select this option if you want to analyze the neighbor list of all of the cells meeting the other criteria.

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Description

Maximum Neighbor List Size

32 Defines the maximum number of recommended neighbors. Note that the higher the number of potential neighbors, the longer it will take for a handset to find appropriate neighbors, conceivably resulting in a dropped call.

Once a potential neighbor list has been calculated for each data point, they are

aggregated by serving cell to produce the recommended neighbor list. This is

compared with the existing list to calculate which are additions, retentions and

removals.

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Appendix F: GSM Diagnosis

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Call Setup Failure


RR Failed An RR Channel Request is not followed by an RR Immediate Assignment with matching establishment cause and random reference within the time period specified by the G_Timeout_ChannelRequest threshold.

Immediate Reject An Immediate Reject message was received.

Another Call Started • Another RR Channel Request with the same establishment cause and random reference occurs more than 200 milliseconds after the RR Immediate Assignment and before the call setup is complete.

• Another RR Channel Request with a different establishment cause or random reference occurs at any time after the RR Immediate Assignment and before the call setup is complete.

CM Service Abort / Reject

A CM Service Abort / Reject message was received.

System Released When the cause code is Not Normal (0-31, 42) in either the NAS message or the RR Channel Release message.

Poor Coverage If ServRxLevSub < G_RxLevSub_Min.

Interference If ServRxQualSub > G_RxQualSub_Max.

Other More investigation is needed. Use other tools and views to refine your understanding of the problem.

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Location Update Failure


RR Failed An RR Channel Request is not followed by an RR Immediate

Assignment with matching establishment cause and random

reference within the time period specified by the

G_Timeout_ChannelRequest threshold.

Immediate Reject An Immediate Reject message was received.

Another Call Started • Another RR Channel Request with the same

establishment cause and random reference occurs more

than 200 milliseconds after the RR Immediate

Assignment and before the call setup is complete.

• Another RR Channel Request with a different

establishment cause or random reference occurs at any

time after the RR Immediate Assignment and before the

call setup is complete.

LU Reject A Location Update Failure message was received.



System Released When the cause code is Not Normal (0-31, 42) in either the

NAS message or the RR Channel Release message.

Other More investigation is needed. Use other tools and views to

refine your understanding of the problem.

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Dropped Calls



the NAS message or the RR Channel Release message.

Missing Neighbor

Handset: If after the drop, BCH is not in the BA list, but

was before the drop.

Scanner: If one of the top 6 BCH is not in the BA list

before the drop.

Handover Problem If stronger neighbors than the serving cell for a period.

See GSM Dragged Handovers.



Other More investigation is needed. Use other tools and views

to refine your understanding of the problem.

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Handover Failure Diagnosis

The diagnosis for Handover Failure is derived directly from the CauseCodeRR

value.

For example:


Handover Impossible

(TA out of Range) Handover Failure message, CauseCodeRR = 8

Channel mode unacceptable Handover Failure message, CauseCodeRR = 9

Frequency not implemented Handover Failure message, CauseCodeRR = 10

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Appendix G: GSM Visualization There are two network visualization features implemented in this page. For each

feature, to determine the analysis radius around the selected site, the user

needs to set the thresholds G_Interference_Radius or use the default

threshold of 10 units. The units for this threshold can be in either Kilometers or

Miles, as set in Tools Preferences General Settings Distance Units.

BCCHColourAdjacentCells() Define an analysis radius within which this visualization is to occur.

Select a site with BCCH g_bcch.

Inside the analysis radius, trigger the analysis for any site with co-channel

interference, upper/lower adjacent channel interference:

If the site has the same BCCH (otherBCCH==g_BCCH) ⇒ Co-interference.

For all the possible related TCHs, if otherTCH[j]==g_BCCH ⇒ Co-interference.

If the site has upper adjacent BCCH (otherBCCH==g_BCCH+1) ⇒ Adjacent

upper.

If the site has lower adjacent BCCH (otherBCCH==g_BCCH-1) ⇒ Adjacent

lower.

For all the possible related TCHs, check if otherTCH[j]==g_BCCH+1 ⇒ Adjacent

upper.

For all the possible related TCHs, check if otherTCH[j]==g_BCCH-1 ⇒ Adjacent

lower.

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As each site can only have one color, the sequence of steps is very important:

the first satisfied condition decides the color of the site in analysis. The colors

used are:

red for co-channel interference

orange for upper adjacent channel interference

yellow for lower adjacent channel interference.

All site information is stored in three structures, one for the co-channel

interference, one for the adj/low channel interference and one for the adj/upp

channel interference. Three tables, sorted by distance from the selected site,

contain information on the sites that neighbor the selected site:

Distance from the selected site

SiteName, Sector

BSIC

%Interference

#InterferedChannels

Channel.

%Interference is calculated as the ratio between the number of channels in

common and the sum of all the channels. In the example below, if the other cell

has 4 channels, 1 BCCH and 3 TCHs, and the selected cell BCCH is equal to one

of the other cell TCHs, the number of channels in common is equal to 2. Then

%Interference is equal to 2/(4+1) = 40%.

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In this case, BCCHColourAdjacentCells, #InterferedChannels is equal to 1. The

Channel field gives the type and the number of the channel that gives

interference, i.e. BCCH 740.

TCHColourAdjacentCells() Define an analysis radius within which this visualization is to occur.

Select a site with TCHs stored in g_tch.

Inside the analysis radius, we trigger the analysis to any site for co-channel

interference, upper/lower adjacent channel interference: for all the g_TCHi

If the site has same BCCH (otherBCCH== g_TCHi) ⇒ Co-interference.

For all the possible related TCHs, if otherTCH[j]==g_TCHi ⇒ Co-interference.

If the site has upper adjacent BCCH (otherBCCH==g_TCHi +1) ⇒ Adjacent

upper.

If the site has lower adjacent BCCH (otherBCCH==g_TCHi -1) ⇒ Adjacent lower.

For all the possible related TCHs, check if otherTCH[j]==g_TCHi +1 ⇒ Adjacent

upper.

For all the possible related TCHs, check if otherTCH[j]==g_TCHi -1 ⇒ Adjacent

lower.

As in BCCHColourAdjacentCells(), each site can only have one color, and so the

sequence of steps is very important: the first satisfied condition decides the

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color of the site in analysis. The colors used are:

red for co-channel interference

orange for upper adjacent channel interference

yellow for lower adjacent channel interference.

All site information is stored in three structures, one for the co-channel

interference, one for the adj/low channel interference and one for the adj/upp

channel interference. Three tables, sorted by distance from the selected site,

contain information on the sites that neighbor the selected site:

Distance from the selected site

SiteName, Sector

BSIC

%Interference

#InterferedChannels

Channels.

%Interference is calculated as ratio between the number of channels in common

and the sum of all the channels. In the example below, if the other cell has 4

channels, 1 BCCH and 3 TCHs, and the selected cell has 2 TCHs that are equal

to the other cell’s BCCH and to one of the other cell’s TCHs, then the number of

channels in common is equal to 4, and %Interference is equal to 4/(4+2).

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In this case, #InterferedChannels is equal to 2. The Channels field gives the

type and the number of the channels that give interference, i.e. BCCH 740, TCH

570, TCH 571.

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MyActix and Support For more information regarding Spotlight, logon to our Extranet: MyActix. After

you’ve register yourself, you can download the latest Actix Software, self-study

modules, and report any problem concerning Spotlight.

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