Relay selection scheme for cooperative communication networks using contract theory

Precise resource allocation such as best relay selection or optimum power allocation improves performance in cooperative communications. In this paper, we propose a strategy to select the best relay nodes in decode-and-forward parallel cooperative relay networks.We apply a contract theoretic framework over the wireless system to formulate an incentive compatible contract. The designed contract would not just stimulate relays to cooperate, but also incite relays to reveal their channel state information in a trustworthy manner. The proposed relay selection scheme is based upon minimizing the cost for the source node to send data to the destination node. However, the source node wishes to maintain a certain transmission rate to the destination node, although there is a constraint imposed on each relay node´s power. Simulation results show that the proposed scheme can improve utility of the source node, compared with the nearest neighbor relay selection algorithm.