Incremental and Complementary Coding Techniques for Cooperative Medium Access Control Protocols

Cross-layer designed cooperative Medium Access Control (MAC) protocols for 802.11 wireless networks have been recently shown to achieve a better performance than the Distributed Coordination Function (DCF). This paper analyses the effects of different channel coding techniques on the performance of cooperative MAC protocols. Different forwarding schemes, inspired by Hybrid Automatic Repeat and reQuest (HARQ) techniques, are evaluated, and some guidelines are given to design codes suited to cooperative MAC protocols. Furthermore, the cooperative network´s saturation throughput and average packet delay are theoretically evaluated using the sphere-packing bound and extending the Markov models used for 802.11 networks. The model is validated performing bit by bit simulations of the cooperative MAC schemes, showing that the theoretical limiting performance are closely approached by efficient coding schemes.