Performance analysis of a cooperative MAC based on opportunistic relaying for ad hoc networks

The paper presents a cooperative MAC based on opportunistic relaying for ad hoc networks. In the proposed MAC, the cooperative scheme will be activated on the condition that the source contended the channel successful, but the destination receives the inaccurate packets because of the channel noise. Based on opportunistic relaying, the neighbor which has the best channel condition to the destination will be selected as the relay to help the source transmitting packets. An innovative analytical model which considers both of the cooperative scheme and the opportunistic relaying is presented to evaluate the performance of the proposed MAC. Simulations are also performed to validate the analytical model. The comparison with the DCF shows the cooperative scheme can achieve substantial throughput performance improvement when the direct link is poor. Furthermore, the paper compares the proposed MAC with the cooperative MAC based on proactive relay selection. The proposed MAC not only has the benefits that required less cooperative overhead and more suitable for distributed networks, but also has the close performance to the cooperative MAC based on proactive relay selection which is shown from the analytical results.