An efficient cooperative retransmission for wireless regenerative relay networks

This paper considers retransmission mechanisms in wireless regenerative relay networks. The retransmission can be realized in a cooperative manner with the assistance of all available relays. This may result in a high overall power consumption due to a considerable number of overlapped packets in the retransmission, especially when the number of relays is large. In this paper, we propose a cooperative retransmission (CR) scheme based on relay cooperation and binary XOR operation to significantly reduce the number of packets to be retransmitted for a more power efficient system with non-overlapped retransmission. Particularly, we derive the error probability of the retransmission decision at the source and relays, which shows that the proposed CR scheme also improves the reliability of the retransmission. Finally, simulation results are presented to verify the analytical findings and show that the proposed CR scheme reduces the number of retransmissions and removes overlapped retransmitted packets.