Relay Selection for Cooperative MAC Considering Retransmission Overhead

Relay node (RN) plays a key role in cooperative communications and RN selection may substantially affects the performance gain. In this paper we address the issue of RN selection while taking into account Medium Access Control (MAC) overhead, which is incurred by not only handshake signaling but also frame retransmissions due to transmission error. We use a theoretical model to analyze the cooperation performance gains of cooperative MAC mechanism, and are thus able to select the optimal relay node. We derive the network saturation throughput of the designed MAC with our RN selection algorithm. Numerical results validate the effectiveness of our analytical model and show that our designed MAC significantly outperforms existing cooperative MAC mechanisms which do not consider retransmission MAC overhead.