Non-binary joint network/channel coding for multi-user ARQ

We propose a novel joint network and channel coding scheme for multi-user ARQ where network coding is employed to combine retransmissions to several users in a packet-based wireless system. Our approach features a joint design of non-binary network coding and trellis-coded modulation and enables symbol-wise iterative network/channel decoding. Our results based on Monte-Carlo simulations for Rayleigh block-fading channels show an improved performance compared to the conventional separate design while at the same time the amount of feedback and the complexity per user are reduced.