The Dynamic Linear Combination Retransmission based on Network Coding in Multicast Network

Network coding (NC) is an efficient way to decline the retransmission and provides a reliable connection in the wireless multicast network. However, in the NC schemes based on XOR, if one coded packet is lost, the transmitter must retransmit the same one until all the receivers correctly receive it. This strategy falls into the routine of ARQ (Automatic Repeat Request), which has already been proved with low bandwith efficiency. Accordingly, in this paper we proposed a dynamic linear combining retransmission(DLCR) strategy and fixed linear combining retransmission (FLCR) strategy based on the random network coding to improve the bandwidth efficiency in wireless multicast network. The key idea of the proposed schemes is to form the coded packet dynamically according to the real-time network status during the retransmission. Besides, we also analyzed the proposed schemes and get the corresponding theory analysis results. The simulations show that our schemes can well improve the efficiency of transmission.