Tuesday, July 9, 2013

Drive Test


Drive Test will ensure the network performance and it is directly related to the QoS of the network. Normally drive tests are conducted by Technical Officers (TO) under the guidance of an Optimization Engineer. In Drive Test we drive on a vehicle which is well equipped to measure network performance. Gathered data are recorded using a drive test tool and we can analyze them later. Reasons for doing a Drive Test:
  • For Network Optimization: changing antenna azimuths and tilts
  • To identify network performance of area
  • To troubleshoot customer complaints
  • To check network coverage
  • After a major change in the network E.g. After a parameter change in site 
  • To check signal levels After commissioning a new site
In addition to these occasions we sometimes conduct indoor drive tests in situations when there are issues inside a building. In such situations a person wearing drive test tool and other required equipment will walk inside the building where we need to collect data. Here we face the problem of receiving GPS location. At such scenarios first a reference GPS point is taken at a location of the building. Then a sketch of the floor plan of the building is drawn on the map of the drive test tool. Then the drive test tool is taken on a path inside the building area in a fixed speed. We should travel on a fixed and steady speed because otherwise recording may not have correct details of the recorded data.

Equipment and Tools used in a Drive Test

I got to know about two Drive Test Tools. They are Ericson ® TEMS and JDSU (Agilent). TEMS is for 2G and Agilent is for 3G. Tool will record the details to a “.log” file.  Equipments used:
  • A laptop computer with drive test tool installed in it
  • Two mobile phones which supports the tool (one in Dedicated mode and other one in Idle mode)
  • GPS module to track location
  • The license dongle for the authentication of the drive test tool
Two mobile phones, GPS module and license dongle are connected to the laptop. We can upload the existing site file to the tool and according to the location of GPS, data will be recorded. When the record is done we can analyze the recorded data later.