Relaying in wireless networks modeled through cooperative game theory

We analyze the capacity of wireless networks in the presence of cooperative relaying by using game theory instruments. Cooperation is approached as a cross-layer interaction between routing and medium access control; the latter is assumed to be based on memoryless time-division multiplexing, where the users have fixed probabilities to access the channel. We investigate the proper cooperation mechanism to be adopted by the users so that a gain is obtained by both those who have their transmission relayed to the final destination and also those who act as relays. Especially, we show how this gain can be directly related to a throughput improvement if the users follow specific access procedures. This incentive to cooperation works not only in an abstract information theoretic context, but also for a more direct personal advantage of the users. Numerical results are shown to confirm the validity of the proposed approach. The adopted methodology is useful both for modeling and performance analysis of communication links in relay networks, and for designing viable protocols which the users have incentives to follow.