Asynchronous two-way relay communication with physical-layer network coding
异步双向中继信道的物理层网络编码

An important issue in physical layer network coding(PNC) is how to deal with the asynchrony caused by transmission environment, such as carrier frequency asynchrony, carrier-phase offset and symbol misalignment. Most previous work assumed symbol transmission was strict synchronization, which could not be guaranteed in practical system. This paper mainly proposes an asynchronous transmission scheme in two-way relay channel with physical layer network coding. The relay solved the asynchronous problem by using BP(Belief Propagation) algorithm. Simulation results show that BP algorithm can reduce performance degradation caused by the signal asynchronous. Symbol offset can reduce the performance degradation due to phase offset.