基于网络编码的双向多中继系统中断概率分析

Outage Probability Analysis of Bi-directional Multi-Relay System Based on Network Coding

网络编码在双向多中继系统中已经得到了广泛地研究,并有效地提高了双向多中继系统的吞吐量。首先本文导出了在译码转发方式时,独立正交信道和多接入信道下基于网络编码的双向多中继系统平均中断概率表达式。Monte Carlo仿真和理论分析非常吻合,验证了理论分析的正确性。之后分析了系统平均中断性能在不同信噪比和不同中继节点个数等多种情形下与功率分配因子的关系,揭示了功率分配因子与系统总功率和中继节点数量之间的内在关系。仿真结果表明,双向多中继系统采用网络编码进行传输时,在独立正交信道下和多接入信道下的功率分配因子取值在区间[0.5,0.6]内能够获得最优的系统中断概率性能,并且多接入信道下的系统中断性能要好于独立正交信道。

Network Coding has been investigated extensively in bi-directional multi-relay system and can improve the throughput of bi-directional multi-relay system effectually.Firstly two outage probability expressions of bi-directional multirelay system on independent orthogonal channel and multiple access channel with decode-and-forward based on network coding are given in this paper and theory analjsis is proved correct by Monte Carlo simulation.Secondly we analyze the system average outage performance at different situation of different power allocation coefficient,SNR and the number of relay,indicating the inherent relationship between power allocation coefficient and total system power as well as the number of relay. Simulation results indicate that optimal system outage performances of bi-directional multi-relay system on the two channels are attained when power allocation coefficient is chosen in[0.5,0.6],and we can see that outage performance of the system on multiple access channel is better than the independent orthogonal channel.