Joint Network and Channel Decoding for HARQ in Wireless Broadcasting System

This paper presents a novel joint network and channel decoding-interference canceling (JNCD-IC) algorithm for HARQ in wireless broadcasting system. In this system, the base station uses network coding for retransmission. In the retransmission phase, JNCD-IC scheme is proposed for the receivers to recover multiple error packets from the composite packet which is formed by XORing error packets from different receivers. Traditionally, receivers can only recovery one error packet from the composite packet using XOR method when it knows all the other packets in this composite packet as a prior, while the JNCD-IC scheme is trying to recovery multiple error packets from the composite packet by treating the network code and channel code as a single parity check product code. Simulation results for Rayleigh block fading channel show a significant increase in throughput compared to the current schemes.