异步双向中继信道的物理层网络编码

物理层网络编码(physical-layer network coding,PNC)中的一个重要问题是,如何解决由于传输环境导致的信号不同步问题,包括载波频率不同步、相位偏移和符号不同步.之前文献大多数都是假设符号发送严格同步,主要研究了异步双向中继信道物理层网络编码方案,中继端利用BP(Belief propagation)算法来解决异步导致系统系能下降的问题,仿真结果表明,利用BP算法可以减小信号异步导致的系统性能下降,相位偏移对系统性能下降影响较大,而符号偏移却可以减小这种性能下降.

Asynchronous two-way relay communication with physical-layer network coding

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.