Dynamic Relay Selection for ARQ Protocol in Wireless Cooperative Networks

A joint consideration about Automatic Repeat re-Quest (ARQ) retransmission scheme and dynamic relay selection for wireless cooperative networks is proposed in this paper. Relays selected for retransmission in ARQ are different from round to round, so that good relays (with good channel condition on average) will be used only once. Each relay quantizes its source-relay channel state information (CSI) and figures out which quantization regions it belongs to. Relays in each quantization regions will be only responsible for one possible retransmission. In this way, much power of these good relays are reserved. Simulation results show that although the proposed scheme will bring certain packet loss ratio (PLR) performance loss, optimizing the choice of thresholds of the quantization will limit this performance loss.