物理层网络编码分组的机会中继

为提升物理层网络编码方案的抗衰落性能，该文提出了一种基于物理层网络编码的机会中继方案(Opportunistic Relaying based-on Physical-layer Network Coding，PNC-OR)，该方案利用物理层网络编码的基本思想、有效提升网络吞吐的同时，通过中继节点的分布式选择，也能够使系统获得多用户分集增益，提高了系统的抗衰落性能。针对双向无线中继信道中端到端信息交换的情形，推导了准静态衰落环境下PNC-OR中多个目的节点接收信息的和容量。数值结果显示：和机会中继、传统网络编码两种方案相比，PNC-OR具有更高的频谱效率，并且随着中继节点的增多，频谱效率也越高。

Opportunistic Relaying of the Physical-Layer Network Coding Packets

To combat fading in wireless channel, an Opportunistic Relaying scheme based on Physical-layer Network Coding (PNC-OR) is proposed, which not only improves the network throughput by network coding ideas, but also achieves the multi-user diversity gain through relay node selection. Focusing on the bi-directional wireless relaying channels, the sum capacity of the destination nodes in the PNC-OR scheme for the quasi-static fading environment is developed. The numerical results show that in contrast to the opportunistic relaying scheme and conventional network coding scheme, PNC-OR scheme achieves higher spectral efficiency.