Multi-relay cooperative NB-LDPC coding with non-binary repetition codes over block-fading channels

In this paper, we propose a cooperative coding scheme to communicate efficiently over multiple-relay fading channels. The particularity of our approach is to rely on non-binary LDPC codes at the source, coupled with non-binary repetition codes at the relays. A simple joint decoding strategy is used at the receiver end, so that the decoding complexity is not increased compared to a system without relays, while preserving the coding gain brought by re-encoding the signal at the relays. We show by simulations that the proposed scheme allows maintaining a constant gap to the outage probability of the cooperative system, irrespective of the number of relays.