Amplify-and-Forward Relaying Based Multi-Relay Wireless Network Coding

This paper extends the amplify-and-forward based wireless network coding (AFNC) for single-relay network to multi-relay network with a chain topology. Direct application of the relaying protocol utilized in the conventional single-relay AFNC to the multi-relay scenario causes two major problems: the phenomenon of back stream of data, which we call data reflection, and inter-hop interference. We propose a distributed relaying protocol for the multi-relay AFNC, which can cope with the data reflection by using locally available information. Moreover, we introduce the technique of frequency domain equalization (FDE) for the transmission and the detection of signals in order to utilize the interference as informative signal. Computer simulation results show that, with the proposed method, the multi-relay AFNC can be realized and the interference is successfully utilized to improve the throughput performance.