Parity Forwarding For Multiple-Relay Networks

This paper proposes a relaying strategy for networks with multiple relays where each relay forwards parities of decoded codewords. This parity-forwarding scheme can be thought of as a generalization of Cover and El Gamal´s well-known decode-and-forward strategy for the classic three-terminal relay channel to networks with multiple relays. As compared to previous multiple-relay decode-and-forward strategies, the parity-forwarding scheme is more flexible and can achieve a higher rate. The proposed strategy can be easily applied to networks with complex topologies. We show that relay networks can be degraded in more than one way, and parity-forwarding is capacity achieving for a new form of degraded relay networks