Combined Denoise-and-Forward and Superposition Coded Physical-Layer Network Coding in Data Length Asymmetric Two-Way Relay Channels

To improve the bit error rate (BER) performance of physical-layer network coding (PNC) in data length asymmetric two-way relay communication systems, a new PNC scheme named combined denoise-and-forward and superposition-based physical-layer network coding (DNF-SC-PNC) is proposed, and the decoding algorithm of the scheme is improved. In the scheme, the mixed information is denoised and superposed in the relay node, which will be broadcasted to destination node. The destination node will use SIC or LLR algorithm decoding. Theoretical analysis and simulation results show that DNF-SC-PNC can provide better BER performance and better throughput rate performance when the data length is asymmetric. Furthermore, we also proved the LLR algorithm can provide better BER performance and better throughput rate performance than SIC algorithm when the data length is asymmetric.