Joint LDPC and physical‐layer network coding with incremental phase pre‐rotation for two‐way relaying

Abstract

To obtain a robust physical-layer network coding (PLNC) for two-way relaying system, the authors propose a low-density parity-check (LDPC) coded PLNC scheme with phase pre-rotation to combat the carrier phase asynchronous in the multiple access stage. At two users, each modulation symbol is rotated according to a predefined incremental phase without the knowledge of carrier phase difference. Decoding simulation and numerical analysis are carried out to evaluate this joint LDPC and PLNC scheme with phase pre-rotation. Simulation results show that this strategy can achieve a significant improvement and a good trade-off between performance and complexity. Protograph-based extrinsic information transfer analysis demonstrates the proposed scheme is robust, which is consistent with the simulation results.