Dynamic method of network coding based retransmission for wireless multicast

In wireless single-hop multicast with network coding based Automatic Repeat reQuest (NC-ARQ) scheme, the sender needs to combine one or several lost packets as one retransmission packet to reduce the number of multicast transmissions. This paper proposes a new scheme, called Dynamic Network Coding based ARQ (DNC-ARQ), to improve the efficiency of the multicast transmissions. The main idea is to allow the BS to select the combination for the lost packets in dynamic range: the BS would not retransmit for a lost packet until an optimum combination is found or the lost packet achieve the maximum delay. We also derive the upper and low bound of DNC-ARQ scheme and give a practical algorithm. Both theoretical analysis and simulation results confirm the proposed scheme hold more efficient and less decoding delay than the traditional NC-ARQ.