Distributed joint optimization of relay selection and subchannel pairing in OFDM based relay networks

Relay selection and subchannel pairing are important issues in OFDM based cooperative wireless systems to improve the system performance and reliability. Most of the relay selection schemes in modern literatures are centralized under the assumption that the overall channel condition is known at the source node, each relay node and the destination node which is impractical. In this paper, we will propose a low computational complexity distributed relay selection and subchannel pairing algorithms under limited channel state information. Through the computer simulation, we found that under the limited channel state information constraint, the proposed algorithm can achieve a much better system performance than the traditional relay selection and subchannel matching schemes and earn most of the system performance of the optimal one.