Abstract
Cooperative communications with another node is a promising method to mitigate signal fading and interference problem for wireless ad hoc networks. A good cooperative MAC protocol can improve network performance, make the network more reliable and reduce energy consumption. The previous cooperative MAC protocols are designed for IEEE 802.11b. Thus recent users use IEEE 802.11g or 802.11n more frequently. We design a cooperative MAC protocol for IEEE 802.11g and can also be used in 802.11n. In our proposed protocol, the relays with similar transmission rates are partitioned to the same group. It can reduce efficiently the time slots to select the better relays to help data transmission. Furthermore, we propose a retransmission scheme to reduce the retransmission time. When data transmission is fail, the backup relays which have received the data frame will help retransmission instead of repeating the retransmission cycle. Simulation results show that the proposed protocol outperforms previous work in terms of increase the network throughput and reduced the average delay time.