dt concise guide

7/28/2019 DT Concise Guide

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DRIVE TESTING USING TEMS

A Concise GuideRevision 1.1

ACETelecom


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Table of contents

GETTING STARTED 4

SETTING YOUR TEMS INVESTIGATION SOFTWARE 6

SETTING UP AND CONNECTING EXTERNAL EQUIPMENT 7

CONNECTING TEMSMOBILE STATION 7CONNECTING GPS 9

RECORDING/LOGGING THE DRIVE TEST 10

SWAPPING LOGFILES 10

TYPES OF DRIVE TESTS 11

IDLE MODE 11HOW TO ESTABLISH A CONTINUOUS/LONG CALLS 11HOW TO ESTABLISH SHORT CALLS 11

READY FOR DRIVE TEST?(SOME IMPORTANT TIPS) 13

BEFORE GOING TO THE DRIVE TEST 13

WHILE SETTING UP AND CONNECTING THE EXTERNAL EQUIPMENT (TEMS OR GPS) 13DURING DRIVE TEST 13AFTER THE DRIVE TEST 13

TRX TESTING USING TEMS 14

COMMON BCCH TESTING DRIVE 15

AMR TESTING DRIVE 16

DRIVE TEST USING MORE THAN ONE TEMS MOBILE 17

SITE VERIFICATION PROCEDURE 18

1.TRXTEST: 182.GPRSTEST: 193.INTRASITEHANDOVERTEST: 20


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4.INTERSITEHANDOVERTEST: 215.COVERAGETEST: 21

CLUSTER DRIVE TESTS 23

AREA LEVEL DRIVES 31

REHOMING DRIVES 33

GPRS LEVEL TESTING 34

FREQUENCY SCANNING 38

MAPPING OF SCANNED FREQUENCIES 43

LAYER 3 MESSAGING 49

LAYER3MESSAGINGINTEMS 52

SOME PROBLEMS AND THEIR REMEDIES 56

WHY MY MOBILE IS SPONTANEOUSLY DISCONNECTED EVERY NOW AND THEN? 56WHY DOES THE MOUSE POINTER STARTS BEHAVING WEIRDLY WHEN I CONNECT MY GPS? 57

REVISION HISTORY 58


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Getting Started

ACE TELECOMwelcomes you to this concise tutorial/document on Drive Testing using TEMSInvestigation GSM. It is the leading air-interface test tool for Wireless Networks.

Getting started gives a quick overview of the TEMS Investigation user interface. The working ofthe TEMS INVESTIGATION is described in more detail in the later part of the document.

Workspace and WorksheetsThe entity that stores all the windows and settings used in a working session is called theworkspace. Only one workspace can be open at a time.

To manage your windows more smoothly, you can divide your workspace into severalworksheets. Up to ten worksheets can be active simultaneously.

ToolbarsThrough the toolbars all the central functions are accessible. Most of the toolbar buttons aremirrored in the menus.

NavigatorFrom the Navigator, you can open presentation windows, change the color ranges of informationelements, and manage your worksheets.

The Navigator is especially useful for configuring the workspace at the beginning of a session.


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Menu BarThe menus mirror most of the toolbars as well as the Navigator's Menu and Worksheets tabs.

Status Bar

The Status bar displays symbols and short messages that indicate the current status of theapplication.


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Setting your TEMS INVESTIGATION softwareThis chapter deals with preliminaries that you must work through before you can start usingTEMS Investigation, such as configuring your TEMS software and connecting external equipmentlike GPS and TEMS mobile station.

1) TEMS Investigation can be opened by choosing:StartProgramsTEMS ProductsTEMS Investigation GSM 5.1.

2) Now go to the Map Worksheet by clicking MAP tab at the bottom of the TEMSInvestigation window.

3) Next thing now is to zoom into the country or city where you want to drive test and addsufficient layers.

4) Adding Layers(for example area map, drive route or any other layer)a. Adding layers is simple. J ust click the Layer Control button at the top of the

Map window.b. Layer Control window will appear and you can easily add new layers (tab files) by

clicking on the Add button and browsing your folders for the requiredlayer.(Remember to keep the layers above the ocean and also the map layer)

c. The new layers will be visible on the Map window as soon as you click OK.

5) Adding Cellfiles (cellfile contains the cell information in the network like Cellname, Cell id,direction, ARFCN, BSIC, LAC, etc)

a. Click on the configuration tab at the bottom of the TEMS Investigation window.b. Now go to the window named GENERAL and double click Cellfile Load

(highlighted in the snap on the right).c. Another window will appear named

PROPERTIES (as seen in the snapbelow). Check on USE CELLDEFINITION FILE. And then browsefor the folder where you have saved

the latest cellfiled. After loading the cell file click OK on

the properties window and go back tothe MAP window to check whether thecellfile has been loaded.

Your TEMS Investigation is now ready to be used and next step is to connect external equipmentlike TEMS and GPS.


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Setting up and connecting External equipment

Connecting TEMS Mobile Station1) Place the external antenna at the roof of your drive test vehicle. It is magnetic and will

stick easily to the rooftop.

2) Connect the connector of the antenna to an adaptor(a wire) that will lead to the jacket ofthe TEMS mobile station.

3) Now place the TEMS MS into the jacket.

4) The TEMS MS is now ready to be connected to the laptop via USB data cable.

5) Connect the TEMS MS to your laptop ports.

When you have plugged an external device (MS or GPS) into a PC port, you must performtwo steps in TEMS Investigation before you can start using it: first to enable the device, then

to connect it (in an abstract sense of the word). From now on in this chapter, the word"connect" when used by itself refers to the operation carried out within the application, not toconnecting the device physically to the port.

Enabling can be done in two ways: either for all devices at once, using the Identify Equipmentfunction (Automatic), or for each device separately (Manual). But its always a nice practice toconnect manually.

6) Automatic enabling can be done by going to the Port configuration window in the

Configuration Tab and clicking IDENTIFY EQUIPMENT button .

7) Manual enabling (preferred to avoid port conflicts) is done using the buttons that looks

like this . (this enables one device at a time)a) When you click the manual enable button a window will appear named

ADD EQUIPMENT.b) In the Port combo box you select the correct COM port. (In our case its

the one other than COM3 and COM16)c) Under Equipment you select the type of external device. Choose "T610"

for the TEMS MS and it will appear as an MS device.d) You can repeat step a, b, c for connecting more than one tems.


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8) To connect a single external device(TEMS):Choose the device in the combo box of the Equipment Control toolbar (at the top of

TEMS Investigation).

And

Click Connect on theEquipment Control toolbar.

9) To connect all external devices:

Click Connect All on the Connections toolbar.

Connected devices are accompanied by a green-light symbol in the combo box. Thesame symbol appears in the status bar and in the Port Configuration window.

Note: If you have a logfile opened, you must close it to be able to connect equipment.

12) If you want to leave an external device plugged into the port, but disconnected in theapplication for the time being:Choose the device in the toolbar combo box.

Click Disconnect on the Equipment Control toolbar.

To disconnect one external device.Click Disconnect All on the Connections toolbar.

For a disconnected device, the symbol representing it reverts to red.


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Connecting GPS1) Connect the GPS to the laptop via the data cable.

2) Manually enable the GPS (as said before manual enabling is preferred to avoid port

conflicts) using the ADD button which looks like this .a) When you click the manual enable button a window will appear named

ADD EQUIPMENT.b) In the Port combo box you select the correct COM port. (In our case its

COM16 because the PCMIA card is already configured at COM16).c) Under Equipment you select the type of external device. Choose

"NMEA0183" for the GPS and it will appear as a GPS device.

3) To connect a single external device:Choose the device in the combo box of the Equipment Control toolbar (at the top of

TEMS Investigation).And

Click Connect on theEquipment Control toolbar.

4) To connect all external devices:

Click Connect All on the Connections toolbar(or press shortcut key F2).

Connected devices are accompanied by a green-light symbol in the combo box. Thesame symbol appears in the status bar and in the Port Configuration window.

Note: If you have a logfile opened, you must close it to be able to connect equipment.

5) If you want to leave an external device plugged into the port, but disconnected in theapplication for the time being:Choose the device in the toolbar combo box.

Click Disconnect on the Equipment Control toolbar.

To disconnect one external device.

Click Disconnect All on the Connections toolbar.

For a disconnected device, the symbol representing it reverts to red.

Note: Place the GPS at some position where you have a clear view of the sky either onthe dashboard or at the back of the car where the speakers are installed.


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Recording/Logging the Drive TestAfter Setting up your equipment and TEMS INVESTIGATION you are now ready for drive test.

The main aim is to recording what you are testing. Recording can be started by simply clickingthe recording button at the top of the TEMS INVESTIGATION window in the recording tool bar. It

is the button with a red circle.

Swapping logfiles

At any time while recording, you can close the current logfile immediately and continuerecording to a new file.

Click Swap Logfiles.The new logfile will be named according to the default format MMDD_nn.log, regardlessof the name you chose for the original file.

There is another thing called quick logging in TEMS. In this you simply set the no. ofmessages per logfile and the logfile swaps automatically.

To do quick logging we:1) Choose Recording Properties... from the Logfile menu.2) A window will appear select the default folder where you want to save the logfiles.3) Then check on the Quick Logging option and type in the no. of messages for the

logfile to swap.


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Types of Drive TestsWe usually come across 3 types of Drive test:

1) Idle Mode2) Short Call

3) Long Call/Continuous Call

or you may asked to use any two or may be all three.

Idle ModeIn idle mode you dont need to try anything. J ust have to connect the mobile and relax keeping aneye on disconnection or dropped Rxlev due to antenna connections.

How to establish a Continuous/Long calls1) For the first time you have to manually dial a no. from your TEMS mobile station.

2) After the first time you can use the redial button in the toolbar at the top of the TEMSINVESTIGATION window.

(In idle mode) It redials the last call;(in dedicated mode:) It terminate the ongoing call.

In the latter case, the receiver symbol is crossed out.

How to establish Short callsWe can generate short calls using the command sequences in the TEMS INVESTIGATION. TheCOMMAND SEQUENCE window can be found in the CONTROL worksheet which can beopened by clicking the Control tab at the bottom of the TEMS INVESTIGATION window.

To add commands we click add in the Command Sequence and an ADD COMMANDwindow appears.

The commands are organized in a tree structure in the left-hand box. Choose the command youwant to add and specify the arguments.

The Command line box at the bottom of the dialog contains the full wording of the command,complete with mobile designation and all arguments.

Click the Add above button to add the command above the one selected in the CommandSequence window.

Click the Add below button to add this command below the one selected in the Command

Sequence window. Click the Close button to close the dialog when you are done with the command

sequence.


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A snap of the ADD COMMAND dialog box can be seen below:

For example if we want to make a call sequence of 60 second call with a delay of 10 secondbetween each call the command sequence will look like this:

For the above sequence we just go to the ADD Command window and select Voice (atthe bottom left of the ADD COMMAND window

Then select the dial command and make changes according to our need.

Like in this case we set the Number as 09122055968 and do not any other of theoptions.

Then we add the a wait of 60 seconds by going to General Command options andselecting wait and changing the seconds options in the wait command to 60.

Then we add in the End Call command from the Voice (at the end of the ADDCOMMAND window).

At the last instance we add a wait of 10 sec to give a delay of 10 sec between twoconsecutive calls


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Ready for Drive Test?(Some important t ips)After you have setup and installed the TEMS and GPS you are now ready to Drive Test.Following are some of the tips that might help during and before you start the drive test.

Before going to the Drive Test Make sure that you have the required data :

o updated cellfile, route that you need to followo and any other information from the person you are reporting to.

You are not missing any equipment at office or at home like GPS, inverter, antenna , etc TEMS mobile is charged because charging during the drive test really wastes time. You have bought batteries for the GPS.

While setting up and connecting the External Equipment (TEMSor GPS)

Be patient and DONT RUSH Handle the antennas with care because they are delicate and usually if one mishandles it

can affect its performance (loss in Rxlevel). While connecting the equipment make sure that you first connect the TEMS mobile and

then GPS. Otherwise you might experience COM port conflicts. Check the Rxlevels of the the tems just to check their is no abnormal behavior.

For example sometimes when the antenna connection is loose you might experience aconsiderable drop in the Rxlev.

If you are using more than one TEMS MS make sure that all of them give the same Rxlevin idle mode. (Compare the Rxlevel at some point where you are being served by thesame cell) If the Rxlev is difference check your external antenna connections.

During Drive Test MAKE SURE YOU ARE LOGGING/RECORDING and that you know the folder you are

saving the log file in. Keep an eye on any disconnections. If there are any disconnections stop logging and

reconnect. And start from the point where the equipment disconnected. If you are not able to reconnect then simply disconnect every external device and try

again. If you are still not able to connect then simply restart TEMS INVESTIGATION. Ifstill you are not able to connect then SIMPLY restart your PC.

Af ter the Drive Test J ust wrap your equipment in a nice orderly manner and make sure that you dont RUSH

because the equipment is really delicate and mishandling can easily damage it. Check everything before leaving the drive test vehicle especially the TEMS Mobile.


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TRX Testing using TEMS

Steps to be followed:- Stand in the main lobe of the sector whose TRXs are to be checked

- Dont be very close to the SITE keep a distance of 100 meter so that the call is nothanded over to some other cell.

- Establish a call and wait for 60 secs- Disconnect the call and establish a call again to check the other TRX- Using the same procedure to check all the TRXs of that sector.- If call cannot be made on any one of the TRXs try for at least 20 times. If still you cant

make a call then note this down.- Also note down any other problems that you observe for example low power TRX,

frequency swap etc.Sometimes if u cannot reach any of the 900 bands it is a usual tactic enabling only 900 band onyour MS. Following steps tells you how to do that:

1) Go to the Control Properties worksheet by clicking on the Control tab at the bottom of theTEMS window.

2) Now go to the Handset control window of the desired MS and right click.3) Now choose properties4) Mobile Properties window for that MS will open.5) Now click on the Band Control tab and disable/uncheck 1800.


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Common BCCH Testing Drive

- The check for common BCCH is just like any other drive test the only thing that we needto observe is that for each sector or segment the BCCH is the same for both 900 and the

1800 band. This can be seen from the snapshot of the Current Channel window below:

As can been seen from the two figures above the BCCH of the two TRX although one is in the900 hopping and the other in the 1800 hopping. This show that common BCCH is workingproperly on this sector.


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AMR Testing Drive

During the AMR test the only change that need to be made in your TEMS configuration that is toenable the TEMS mobile stations AMR setting. Rest of the test depends on the RF engineer who

sends you for the Drive. It depends on how he wants the comparison result. For example he mayask you to set one MS on only AMR(Full or Half rate or both) and one non AMR(Full rate, EFR oretc).

Steps to enable AMR on your TEMS MS:1) Go to the Control Properties worksheet by clicking on the Control tab at the bottom of the

TEMS window.2) Now go to the Handset control window of the desired MS and right click.3) Now choose properties4) Mobile Properties window for that MS will open.5) Go to the Speech Codec tab and check on the AMR full and AMR Half rate.


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Drive Test using more than one TEMS Mobile

Connecting more than one TEMS MS has already been explained in the CONNECTINGEXTERNAL EQUIPMENT chapter. So the task now is to open new Radio Parameter or CurrentChannel windows for the second MS or the third MS.(MS2 and MS3)

For example, if you want to open a Radio Parameter Window for the second TEMS MS (MS2)just follow the following steps:

1) Click on the Presentation tab at the top of the TEMS INVESTIGATION window2) Go to GSM3) Now select Radio Parameter4) A new Radio Parameter window will open.5) Right Click it6) Select Properties7) And change the MS to MS2 in the Properties Dialog box that opens.8) Click OK to make the changes.

Simple isnt it.

A snapshot of the Radio Parameters Properties dialog box can be seen below.


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SITE VERIFICATION PROCEDURE

The site verification process outlined by Nokia consists of five important tests. The testsare mentioned below and one should carefully read and follow the details in order to

successfully complete the site verification process.

The tests to be carried out are:

1. TRX test2. GPRS test

3. Intrasite Handover test

4. Intersite Handover test5. Coverage test

1. TRX TEST:

To carry out the TRX test following guidelines should be taken into account

- Stand in the main lobe of the sector approximately at a100 meters distance

- Make a call on the test number and wait for approximately 30 secs

- End the call and establish another call and check if the call has gone on another TRX sothat it could be verified as well

- Repeat the procedure until all the TRXs have been verified

- If the call is not established on a particular TRX, attempt at least 20 times and if the callstill does not establish on that TRX, take a note of this and report it to the person in

charge

- Repeat the procedure for all the sectors of the site

Tips:

The drive tester might experience a scenario in which the call establishes on the 1800

MHz band but fails to do so on the 900 MHz band. This occurs due to low traffic on a

particular cell site. To suppress the 1800 MHz band one has to uncheck 1800 from the

band control properties of the Mobile Station. This would lead the mobile to make callsonly on the 900 MHz band.

Issues:

There are two issues which concern the radio planners in the TRX test; one being LowPower TRX and the second being the Cross Feeders.


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Low Power TRX:

This refers to different RX levels measured form different TRXs in the same sector. The

deviation can vary from a few dB to more than 25 dB.

Cross Feeders:

As the name suggests, this happens when the feeder cables of two different sectors are

crossed, which in turn leads to the fact that the coverage areas of the two adjacent cells

are crossed.

If the drive tester finds any such issue during the drive test he/she should immediately

inform the person in charge.

2. GPRS TEST:

This test is done to ensure whether or not General Packet Radio Service (GPRS) isenabled on a site. This test can be performed by browsing some sites in the TEMS

handset. This is achieved by clicking the internet options in the main menu of the

TEMS handset.

Once the packets start to

transfer, TEMS goes into

the packet mode as shown

in the figure below. Withthis data transfer is

ascertained.


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All the sectors of the site are to be checked one by one and if any inconsistency is found,the drive tester should inform the RF Engineer.

Other GPRS measurements, if required, can be obtained from the Data Services

presentation menu

3. INTRASITE HANDOVER TEST:

This test is carried out to make sure that the handover between adjacent sectors of a siteare successfully taking place.

For example if a certain site has three sectors namely A, B & C. The drive tester would

have to check handovers from A to B to C to A (clockwise) and A to C to B to A(anticlockwise). Separate logfiles are maintained for both directions.

Tips:

Sometimes these handovers cannot be verified by the drive tester due to the fact there is

no road through which he/she can access the sectors consecutively. If this happens, the

drive tester would have to force the handovers between the sectors. This is done byselecting the source channel and the target channel through the dedicated mode tab in

the mobile properties window. The figure below explains this.


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4. INTERSITE HANDOVER TEST:

This test is carried out to ensure that a particular cell hands off of a call bi-directionally to

all of its first tier neighbors. To perform this test the drive tester has to initiate a call from

the cell whose intersite handover test is to be conducted and move towards all of itsneighbors. Once this is done the drive tester would move back to the original cell and let

the handovers take place. If any discrepancy is found the engineer should inform the RF

planner to make the necessary changes at the BSC.

5. COVERAGE TEST:

This test is done to verify the coverage footprint of a cell site. This is also performed on

all the sectors of a site. To execute this test the drive tester has to lock the frequency of a

particular sector and disable the handovers as shown in the figure below.


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Once this is done, a call is established and the drive tester drives in the line of sight ofthat sector until and unless he/she reaches a point where the call is dropped due to low

RX levels or bad quality. When the network is in its initial stages i.e. when frequency

reuse is not very tight, the call usually drops due to low RX levels, but when more andmore sites are added to meet the capacity needs, the call drops generally due to bad

quality caused by increased interference.

To reset handovers and frequency lock press the button.Drive test results will give the penetration level of signals in different regions of the

network. These results can then be compared with the plans made before the networklaunch. In urban areas, coverage is generally found to be less at the farthest parts of the

network, in the areas behind high buildings and inside buildings. These issues become

serious when important areas and buildings are not having the desired level of signal evenwhen care has been taken during the network planning phase. This leads to an immediate

scrutiny of the antenna locations, heights and tilt. The problems are usually sorted out by

moving the antenna locations and altering the tilting of the antennas.

Precautions:

While conducting this test, the drive tester should confirm that he/she has locked on theproper frequency and the handovers are disabled as if this is not done vigilantly, he/she

may have to redo the drive again (because handovers might take place).


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CLUSTER DRIVE TESTS

Usually, new sites are grouped in clusters of comparatively the same number of sites

(usually 10 to 15 sites per cluster). Now, as already explained every new site integratedhas to go through a site verification procedure before being commercialized. In addition

to this a more comprehensive drive test is required which covers all major and minorroads for every cluster before acceptance by customer.

Generally, the drive tester is provided with a drive route of every cluster before driving it.But, as the maps are not very accurate and are flexible, new routes can be added if found

suitable by the drive testers and in turn the network planners.

A cluster drive route will somewhat look like the figure below:


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The red lines shows the cluster boundary and the blue lines show the drive route to be

followed inside the cluster.

The purpose of cluster drives is to identify and investigate the errors made by network

planners. These can be frequency plan mistakes, adjacency definition problems, as well

as parameter mismatches.

Now, to perform the cluster drive test, the drive tester would have to connect two TEMShandsets. One would be used for short call and the other for long call.

SHORT CALL: (MS 1)

To set a mobile in the short call mode, the drive tester has to start a call sequence. The

call sequence setup procedure is outlined below:

First of all, click the add command button in the Command Sequence

window.


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Click Dial in the Voice Tab. Select the Equipment Name. Here MS1 is selected. Click Number/MS box and enter the number to be dialed. Here for example the

testing number *009 is entered.


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Click Wait in the General Tab. Enter the number of seconds for which the call should remain established.


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Enter the number of seconds for which the mobile should remain in Idle mode.

Select the first command in the command sequence box and using right click ofthe mouse enter into the properties.


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Check the Repeat box and enter Infinite. The loop will repeat for infinite number

of times.


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Final view of the command sequence box.

The short call gives us information about Call Setup Success Rate etc. It is useful inidentifying the cells on which calls are not established due to any reason.

LONG CALL: (MS 2)

This is also known as the continuous call. This is set up by dialing a testing number and

keeping the mobile in the dedicated mode until the cluster drive is completed. This isuseful in identifying handovers, missing neighbors, adjacency problems etc.


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AREA LEVEL DRIVES

Area level drives are conducted usually for major cities, metropolitan areas etc. This

drive is somewhat similar to a cluster drive, the difference just being that a third TEMShandset has to be connected as MS3 for GPRS testing.

The drive route to be followed is not as comprehensive as the cluster drive route, only the

major roads have to be driven (specifically the cluster boundaries), but still it is beneficial

to discuss the drive route with the Radio Frequency Planner before leaving for drive.

The figure below shows the city of Peshawar, Pakistan and its proposed area level drive

route.

As can be seen above, only the major roads need to be covered.

Now, coming to the testing part. The first two TEMS handsets MS1 and MS2 are to be

connected in the same manner as done before for cluster drives. The MS1 would be used

for generating a call sequence, as discussed earlier, and MS2 would be used for the longcall.

A third TEMS handset is connected as MS3, and is used for GPRS testing, an essential

component of the area level drive. Once MS3 is connected with the first two in place, oneis ready to perform the area level drive. The GPRS testing, in this case, is done by

browsing sites randomly in the TEMS handset until the drive is completed, to make surethat Packet Data Protocol context is activated and sites are allowing GPRS traffic.


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The drive tester should inform the Radio Frequency Planner if he/she observes any

inconsistency or flaw. The engineer should make sure that there are no adjacency errorsor handover failures etc.


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REHOMING DRIVES

The process of rehoming refers to the activity of moving a BTS from the control of one

BSC to another due to various reasons such as capacity enhancement, to shed load off the

BSC etc.

The rehoming drive is done to ensure that sites are properly created and defined at theMSC. This relates to adjacency definition at intrasite and intersite level. The call setup at

each cell also needs to be checked.

To perform this test, a TEMS handset is connected in the usual manner. Then, for every

new site created (rehomed) the drive tester would have to stand in the main lobe of each

cell and setup two calls to ensure whether or not site is allowing traffic. After ensuring

proper call setup, an intrasite handover test has to be completed both clockwise andanticlockwise. When done, the drive tester would have to check intersite handovers of

that particular site with its first tier neighbours to make sure that the adjacencies are

properly defined at the switch. (The details of each test are mentioned in the SiteVerification Procedure)

Any discrepancies such as handover failures, call setup failures, missing neighbours etc.should be immediately notified to the Radio Frequency planner because the sites rehomed

are usually those ones which are already on-air(commercialized) and issues pertaining to

them cannot be held for long.


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GPRS LEVEL TESTING

General Packet Radio Service testing is done to ensure that the service is active on all thesites to be analyzed. The procedure to perform this test is not very complex.

First of all the DT engineer has to configure GPRS settings in his/her TEMS handset. Thesettings are given below (for Telenor and T610 handset):

Go to Menu by pressing the joy stick Go to connectivity and click Data Comm. In Data Communication click Data Accounts Click on Create New Account Check GPRS Data Type the Name of Account Telenor

Go to APN, click edit and write wap and click OK Go to User ID, Edit and write Telenor and then press OK/Save. Same

procedure should be followed for Password.

(Please note that User ID and Password are Case Sensitive) Save all the settings Go back to connectivity and click WAP Options Click WAP Profiles Click New Profile and write Telenor WAP Press OK and edit connecting using. Select Telenor WAP Edit IP address and write 172.18.19.11 and press OK Press Save Your GPRS is now configured

The drive tester has to connect the Mobile Station (MS) following the usual procedure.Now, to test the GPRS activity in an area, one has to drive through the region and browse

websites on the internet. While traversing the area the DT engineer has to make sure thathe/she has checked the GPRS activity on all the sectors of the sites that are in that region.

All the data throughput details can be obtained from the data window in the TEMSInvestigation software.

GPRS Line Chart tracks GPRS performance, including events occurring during the data

service testing.


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GPRS Line Chart Sliding Window is the same as GPRS Line Chart but with averaging

of throughput values. The length of the averaging window is user-configurable: Open theGeneral window, right-click "GSM specific", and set the length in seconds.


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GPRS Status Shows the current state of the GPRS connection as well as the distribution

of channel coding scheme use.

Data Bytes Sent/Received shows the total number of data bytes sent and received at

various protocol levels.

Data Throughput shows current throughput and error/retransmission rates forGPRS/EDGE.


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Data Timeslots shows the timeslots currently used on the uplink and downlink for GPRSor HSCSD, as well as the utilization, performance, and channel coding scheme usage for

each timeslot.


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Then, click on the properties in the scanning menu.

The following window appears. Check manual selection and click select

Now, check the channels to be scanned (network dependent) and click OK.Please confirm the selection from the RF Planner.


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After this, click advanced from the measurement settings window and checkDecode BSIC and click OK.


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All the settings required are now complete, and the drive tester is ready toperform the test. Click the start scanning button

The mode in the Current Channel window would change from idle toscanning as shown below.

The measurements can be taken from the scanner bar chart.


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Mapping of Scanned Frequencies

Problem:

The MAP window in TEMS Investigation GSM maps the samples in idle anddedicated correctly but is unable to map when frequency scanning activity is performed.

Solution:

In the MAP window, the drive tester usually monitors RxLev (received signal strength)

or RxQual (received quality) in idle and dedicated mode drive tests. The RxQual can

only be plotted in the dedicated mode and NOT in the idle mode.

Now, to plot samples when conducting a frequency scan, the drive tester has to changethe theme in the MAP window in TEMS as shown by the snapshots below:

Click the (Add / Edit Theme) Button in the TEMS MAP window.

Then, when the Theme Settings window pops up, click the + sign next to thecoverage layer.


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Then, double-click on whatever is shown inside the coverage layer.

Select the Mobile Handset that is being used for frequency scanning. (It might beMS1 or MS2, select the one you are using, usually MS1).


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Then click on the (Select Color IE) button.


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From the list, now click on the Strongest Scanned ARFCN and the pressselect as shown below

Once the range has changed to Strongest Scanned ARFCN click OK.


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The Theme Settings window will also show the Strongest Scanned ARFCNas below. Now, click Close


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Once all of this is done the drive tester would be able to observe mapped samples of the

scanned frequencies/channels.

Now the drive tester is ready to conduct the frequency scan by following the

guidelines given in the Frequency Scanning document.


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LAYER 3 MESSAGING

Signaling protocol structure in GSM

Layer 1 is the physical layer. Layer 2 is the data link layer. Layer 3 is the GSM signaling protocol.

Layer 3 - GSM signaling protocol. Layer 3 is itself divided into three sub-layers.

Radio Resource Management Mobility Management Connection Management

Radio Resource Management (RR-Layer)

The RR-Layer is concerned with the management of RR-session, which is the time that a

mobile is in dedicated mode, as well as the configuration of radio channels. In additionRR-Layer manages power control, discontinues transmission and reception, and

handovers.

Handover (handoff) is switching of an on-going call to a different channel or cell.

There are four types of handovers

Switching channels in the same cell. Switching cells under control of the same Base Station Controller (BSC)


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Switching cells under the control of different BSCs, but belonging to the sameMobile service Switching Center (MSC)

Switching cells under control of different MSCs.

The first two types of handover, called internal because they involve only BSC, and MSC

is notified only on completion of the handover.

The last two types of handover, called external because they involve MSC.Handover may be initiated by MSC (traffic balancing) or by mobile unit. The mobile

unit always scans Broadcast Control Channel of up to 16 neighboring cells, and forms alist of the six best candidates for possible handover. This information is transmitted to

current Base Station at least once per second. BSC and MSC use this information for

handover algorithm.

One of the problems while making handover decision is whether the poor signal quality is

due to physical interference or mobile having moved to another cell. There are two basic

algorithms for making handover decision:

Minimum acceptable performance: If signal degrades beyond some point, thentransmission power is increased. If power increase does not lead to improve then

handover is performed. Disadvantages: increasing transmission power may cause

interference with neighbor cell.

Power budget: Uses handover to improve transmission quality in the same or lower

power level. This method avoids neighbor cell interference, but is quite complicated.

Mobility Management (MM-Layer)

Manages problem that arise from mobility of the subscriber. The ideal situation is whensystem always knows where the subscriber is located (what cell) in each moment. But

this will cause the subscriber to update the system on every move, and this means a lot of

obsolete update messages, wasting bandwidth. Another extreme situation is when system

never knows subscribers position, but this will cause the system to look for the user overthe whole geographical area, that means a lot of paging messages on every terminating

call. Strategy used by GSM is as following, group of neighbor cells is grouped in one

location area and subscriber updates its position when moving from one location area toanother. Paging is done only in the current location area. The only question is "what

division of cells to location areas is optimal?". There are various algorithm for solving

this problem, they are mostly based statistical data.


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As seen from Figure, when a subscriber registers to MSC it sends registration message

that contains subscribers information. MSC updates its VLR and sends a message tosubscribers HLR.

Authentication and security

Since the radio medium may be accessed by anyone, authentication is used to prove that

the users are who they claim to be. Each subscriber is given a secret key that is recorded

in subscribers SIM and Authentication Center (AuC), during authentication AuCgenerates a random number that is sent to mobile. Using the secret key and this random

number mobile produces a response using ciphering algorithm A3. The response number

should be equal to the one calculated by AuC.

The same initial random number in conjunction with secret key is used to generate the

ciphering key using A8 algorithm. This ciphering key together with TDMA frame

number is used compute a sequence that is XORed with the sent data.

Connection Management. (CM-Layer)

An incoming mobile termination call is directed to Gateway MSC (GMSC). GMSC isbasically a switch, which is able to interrogate the subscribers HLR to obtain routinginformation. The routing information that is returned to GMS is the Mobile Station

Roaming Number (MSRN). MSRN are related to the geographical numbering plan, and

not assigned to subscribers. To obtain subscribers MSRN, subscribers HLR have to

query subscribers current VLR.


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LAYER 3 MESSAGING IN TEMS

Layer 3 messages in TEMS give us a lot of information regarding power control,

discontinuous transmission, handover/ handover failures etc.

For power control and DTX, the drive tester would have to readSystem Information

Type 6.

Handover Command gives us information about the handover which is about to takeplace


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The engineer can also edit the properties of the Layer 3 Messages by right clicking in the

window.


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One can then filter only the required messages.


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Some Problems and their Remedies

Why my mobile is spontaneously d isconnected every now and

then?

USB Legacy SupportUSB Legacy Support must be turned off in BIOS. For information on how to do this,please consult the user manual for your computer.

Advanced Power Management (APM)Advanced Power Management (APM) should be disabled if possible, since it may causedisconnects in TEMS Investigation. The reason that this can happen is that APMsometimes switches off the communication circuits to save power. This may occur evenwhen a mobile station is connected and communicates with the PC on a regular basis.For information on how to disable APM in BIOS, please consult the user manual for yourcomputer.

Windows Power ManagementYou must disable all power management routines in Windows. For further instructions,please consult the documentation for the variety of Windows you are using.

Screen Savers and Energy Saving FeaturesYou should make sure that the computer used for measurement and recording does notgo into any kind of standby mode:Disable the Windows screen saver under Control Panel Display Screen Saver. In thesame dialogs, make appropriate settings under "Energy saving features..." so that thesefeatures are never activated during measurement.Disable any other screen savers.

Port-scanning SoftwareYou should not have any software installed that periodically scans COM or USB ports, forinstance Microsoft Outlook synchronization software from Sony Ericsson (Extnd Connect)or Nokia (Nokia PC Suite). The reason is that such software may cause difficult connectproblems in TEMS Investigation.

Automatic Updating of SoftwareSoftware that uses an "auto update" function to receive automatic updates from a website over a dial-up connection should be disabled.

IR PortThe IR port on your PC may need to be disabled, since it may interfere with the ordinaryCOM ports. Please consult the user manual for your computer regarding how to disablethe IR port.

BluetoothBluetooth must be disabled on the PC.


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Why does the mouse pointer starts behaving weirdly when Iconnect my GPS?In some cases Windows 2000/XP will mistakenly identify an NMEA GPS as a Microsoft Serial

BallPoint, i.e. a type of mouse. You will then lose control of the mouse pointer, and the pointer willstart moving around on the screen.

If this occurs you need to disable the Microsoft Serial BallPoint device in Windows. The easiestway to do this is as follows:

Disconnect the GPS from the PC. From the Control Panel, open the Device Manager. Now connect the GPS. In the device list under "Mice and other pointing devices", a new

mouse device "Microsoft Serial BallPoint" will be displayed. Disengage the power supply to the GPS. The Microsoft Serial BallPoint device will remain visible in the list for some seconds;

during this period it is possible to open the device property page without interference fromthe mouse pointer.

Right-click the Microsoft Serial BallPoint device and choose Properties. In the Device usage combo box, choose "Do not use this device (disable)". This disables

the Microsoft Serial BallPoint device.


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REVISION HISTORY

Version Author Notes

1.0 Arsalan Shabbir Sipra First Version

1.1 Syed Ahmed Saad Abid Added:

Site Verification Procedure Cluster Drive Test Area Level Drive Test Rehoming Drive GPRS testing Frequency Scanning Mapping of scanned

channels Layer 3 messaging

dt concise guide

Documents