Performance analysis of a cooperative MAC

A good approximate analytical formulation of the saturated throughput of a Cooperative MAC (CoopMAC) is presented via a two-dimensional discrete-time Markov chain rather than using an approximation. A helper node is used to relay packets from the source node to the destination node within a coverage via a faster two-hop link if possible. The analytical model is formulated with a number of data rates and their corresponding distances. The critical probabilities that at least a helper node exists in different regions to relay packets are explicitly derived through areas of the intersection of the coverages of the source and destination nodes using different data rates to the helper node. By using the weighted sum of the probabilities of the statistics of each of the stations, the saturated throughput of CoopMAC protocol is explicitly derived. Numerical results of the saturated throughput show that the agreement between the simulation and the new analytical results for CoopMAC is very good.