Distance Spectrum and Performance of Channel-Coded Physical-Layer Network Coding for Binary-Input Gaussian Two-Way Relay Channels
The authors investigate a Channel-coded Physical-layer Network Coding (CPNC) scheme for binary-input Gaussian two-way relay channels. In this scheme, the codewords of the two users are transmitted simultaneously. The relay computes and forwards a Network-Coded (NC) codeword without complete decoding of the two users' individual messages. They propose a new punctured codebook method to explicitly find the distance spectrum of the CPNC scheme. Based on that, they derive an asymptotically tight performance bound for the error probability. Their analysis shows that, relative to the single-user scenario, the CPNC scheme exhibits the same minimum Euclidean distance but an increased multiplicity of minimum distance error events.