A Novel Adaptive Cooperative MAC Protocol for Wireless LANs

In this paper, we propose a novel adaptive cooperative medium access control (MAC) protocol, called ACoopMAC, that adopts new frame control formats and is completely backward compatible with the legacy IEEE 802.11 distributed coordination function (DCF). To adapt to dynamic channel variation and network topology, the sender selects either direct transmission or cooperative transmission adaptively based on the instantaneous channel measurements. An extended analytical model based on elementary conditional probability is adopted to evaluate throughput and average delay performance of our proposed protocol. Analytical and simulation results show that ACoopMAC can improve the throughput performance and substantially reduce system delay, compared to CoopMAC protocol.