研究表明基于无线信道的广播特性,网络编码技术能够显著降低多播通信中的传输时延。多源多播模型中,在任一源节点已知其他源节点信息的条件下,现有传输方案能够确保系统时延最小化。本文在其他源节点信息未知时,对现有多源多目的单中继模型应用网络编码后的时延性能进行分析,并将该模型推广到多中继模型,提出了基于网络编码和机会中继选择策略的MR-OPP-NC方案,并在译码转发机制下,利用中断概率量化了应用网络编码前后的时延性能,仿真表明本文所提MR-OPP-NC方案与未使用网络编码的机会中继方案相比较,能获得显著的时延增益。
Research work has shown that taking advantage of the broadcasting nature of wireless channel network coding across multicast communication can significantly reduce system delay.In multi-Source multicast scenario,with the condition that each source has priori knowledge of other sources,existing transmission schemes can insure systematic delay minimum.In this paper,we analyze the delay performance of network coding for multisource-multidestination single-relay scenario without the above mentioned condition. Moreover,we extend the scenario to the multi-relay scenario,simultaneously proposing the MR-OPP-NC scheme based on network coding and opportunistic relaying selected strategy.We apply outage probability to the quantification of the delay performance of Network Coding with decode-and-forward(DF)strategy.Simulation results confirm that in contrast to opportunistic relaying scheme without network coding MR-OPP-NC scheme proposed can get significant delay performance gains.