Cellular Drive Test

Hello everyone. Let me try to post a simple documentation about one of our activities in MobileCommLab, drive test. After some research and held trainings at our campus since last year, I don’t think it’s bad to share about drive test here. Why? Because some of my friends want to learn this, but they don’t have much resource to pay for the training fees. If you find this post useful and maybe you’re interested to learn more, our research lab is always open to anyone for deeper discussion and practice. Feel free to ask any lab assistants you meet in the lab. :)

In general, Drive Test (DT) can be defined as the methods used to determine the actual condition of the radio performance of a service provider (operator) by collectiong the data in certain area.
Here are some of functions of DT:

  • Analyzing the causes of customer complaints of a service
  • Find problems or maintenance on the radio network
  • To analyze the results of the optimization process
  • To ensure its services performance remain satisfactory by conducting regular DT

There are several commonly used software for drive testing, such as TEMS Investigation (from Ericsson), or the Nemo Outdoor (from Nokia). The one that our campus has in MobileCommLab is TEMS softwares and handsets. We could use TEMS 6 for GSM or TEMS 8 for UMTS(WCDMA) drive test. Now, here’s the steps in DT :

1. Drive test equipments preparation

Before perform a DT, we should make a checklist of hardware used, i.e.:

  1. Laptop with charger and USB hub
  2. License dongle for TEMS 8
  3. TEMS handsets, charger, and data cables
  4. 2G/3G SIM cards
  5. GPS and data cable
  6. Inverter and the cable terminal
  7. Battery (for GPS) and the battery charger

Then do the required software checks, i.e.:

  1. TEMS Investigation 6 or 8
  2. HASP Emulator (for TEMS 6)
  3. Handset driver or PC Suite (T68i, Z800, or K800)
  4. GPS driver

2. Workspace configuration

While doing DT, not all parameters need to be analyzed. Therefore, it’s necessary to arrange our workspace properly for easier analysis of DT parameters. For example in 2G (GSM) DT, arrange the workspace like the following picture:

(picture will be uploaded later)

Description of windows used:

  1. Open Worksheet Map and minimize the size of the map window
  2. GSM Serving + Neighbors (Presentation -> GSM -> GSM Serving + Neighbors): to display the serving cell (Serving / Active Set) and neighboring cells (Neighbor Set)
  3. GSM Radio Parameter (Presentation -> GSM -> GSM Radio Parameters): to display the indicator / radio parameters of GSM system such as RxLev, RxQual, FER, SQI, TA, etc.
  4. GSM Current Channel (Presentation -> GSM -> Current Channel): to provide informations of channels and the cells in use
  5. GPS (Presentation -> Positioning -> GPS): to know the position of lattitude, longitude, and monitor vehicle speed
  6. Equipment Configuration (Configuration -> Equipment Configuration): to adjust the equipment properties used
  7. Command Sequence (Control -> Command Sequence): to run repeated commands on the handset continuously and automatically
  8. Events (Presentation -> Signaling -> Events): to display the event is in progress

3. Port Configuration

We need to know the port where a GPS driver, handset, and the data cable is installed in order to be recognized by DT software. Note the port number of the devices we use at DT. Open Device Manager by right-clicking My Computer, Properties, Hardware, Device Manager. Then find the modem, double click on needed devices, then click the Modem tab. Remember, for the data cable, the port number is always smaller than the port number of the mobile phone.

Then, in the TEMS Investigation software, do the following:

  1. Open the Equipment Configuration window, then click the plus icon
  2. Select port for the handset / MS (e.g. COM5) and its data cable / DC (e.g. COM4)
  3. After all ports are configured, and the dongle’s inserted, connect all devices by clicking on Connect All / F2 (green colored)
  4. If you want to disconnect (after the DT finished), disconnect all by clicking on Disconnect All (red colored)

4. Command Sequence Configuration

Command sequences required for such processes e.g. calls, sms, etc. They can be automatically repeated while DT.

Here’s an example configuration using the TEMS 8 command sequence :

  1. Click Edit (pen and paper image at button) to edit the new command
  2. Then enter the Loop (General -> Loop) and click add to the bottom button. Type 1000 in the Time / Count Loop
  3. Then enter the Dial command and click insert button so the Dial command is in the Loop. Then enter Phone Number and Duration as needed. For example the duration of the Long Call 120 and 15 for the Short Call
  4. Then select the Wait (General -> Wait) and click down button so the wait be after Dial in the Loop. Enter Wait Time 15

5. Map Configuration

While drive testing, map is needed to analyze where we stand compared to the cell position, condition of DT area, etc. Steps to configure the map, i.e.:

  1. In the layer control, Remove all the layers except Pinpoint, Cell, Event, AMR, RF Quality, and Coverage Layer
  2. After that, Add DT area maps
  3. Then enter cellfile. Configuration -> General -> Cellfile Load

6. Configuring the Notebook

Power Management
Before the DT, we should adjust the laptop to be always on. Open Power Options from the Start -> Settings -> Control Panel -> Power Options. Set Power schemes laptop: Always On.

Virtual Memory
Virtual memory is required because the DT need high memory resource. Steps to set the virtual memory are:

  1. Start -> Settings -> Control Panel -> System.
  2. On the Advance tab -> click Performance.
  3. Click Change in the virtual memory. Set the value as needed. It’s better to use more than recommended size

7. Begin drive testing

  1. Configure recording properties. Click Logfile -> Recording Properties
  2. Select recording folder. Click Browse -> Choose the folder
  3. Select Quick logging and setup size of swap file “after reaching message “ to prevent a huge size logfile
  4. Open saved workspace with the map and cell file
  5. Connect all equipments by clicking green colored connect icon / F2
  6. The windows in the workspace will be filled and sounds will come out for running events
  7. Lock the handset RAT (Radio Access Technology) into GSM only or UMTS only
  8. Start drive test by clicking record button, then click start Command Sequence
  9. When all DT route has finished, wait untill call ended, then stop command sequence, and stop recording.

Summary : Start Record Logfile –> Start Command Sequence –> Stop Command Sequence –> Stop Record Logfile

References :

  • TEMS Investigation Manuals
  • MobileCommLab Drive Test and Optimization Training Modules
  • Orinaica’s blog at wordpress.com
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