Reliable Cooperative MAC Protocol in Ad Hoc Networks under Bad Wireless Channel Environments

In this paper, a new reliable cooperative MAC protocol, which can enhance the system throughput under bad wireless channel environments, is proposed, and the protocol´s performance is evaluated with a computer simulation. The system throughput and average delay, except queuing delay, are used as performance metrics. The numerical results show that the scheme proposed in this paper provides 24 more system throughput than the rDCF scheme. On the other hand, the proposed scheme has a higher system performance in the average delay when the number of terminals is small but provides slightly worse system performance when the number of terminals increases. That is because the system performance is mostly dominated by channel contention when the number of terminals becomes large and because retransmission timers after transmissions of CRTS and DATA frames are set with a greater value than the rDCF scheme.