The  AVL(Automatic Vehicle Location) systems is  consisting of a Tr-band GSM/GPRS data Module and GPS receiver .

  The tri-band GSM/GPRS data module is designed to work with  European E-GSM 900 and also  DCS 1800 MHz . GPRS multi-solt class 8 and terminal class B is supported.
  This Class B data module can be connected to a packet data network, i.e. Internet or an intranet, and at the same time be able to be paged for incoming telephone calls(or circuit switched data calls).Therefore a user can be connected to a packet data for a long time(always connected)and at the same time not miss any telephone calls.  
  This data module supports all four coding scheme from CS-1 through CS-4,thus it can support download speed of 36.2 kbps for coding scheme 1 up to 85.6kbps for coding scheme 4.It also supports upload speed of 9.05kbps for coding scheme 1 up to 21.4kbps for coding scheme 4.