Performance Analysis of Downlink GPRS Traffic after a BTS Failure

The data traffic is burstier and has longer connection time as compared to voice traffic. Global system for mobile (GSM) was developed to carry the voice traffic and it is not suitable for carrying data traffic. General packet radio service (GPRS) has been well integrated in the GSM networks to accomplish efficient spectrum utilization for data traffic. Serving GPRS support node (SGSN) is the main module of GPRS network which is responsible for delivering data packets to mobile stations via base transreceiver station (BTS) and vice versa. Depending upon coding scheme, each packet has some forward error correction capability and retransmissions are also done if errors are more. If a BTS stops functioning (i.e. fails) then packets could not be delivered to users of this area. In this work, it is suggested to use the PDCHs, which were assigned to the failed cell, by transmitting them from neighbor BTS. It will assure some service in the failure affected area at the cost of increased cochannel interference, thus bit error rate (BER), decreased throughput etc to cochannel users. Quantification of the impact of BTS failure on the performance of GPRS downlink traffic is main goal of this paper.