D2D网络中基于牺牲节点的网络编码协作重传策略

Network Coding Cooperative Retransmission Strategy Based on Sacrificial Node in D2D Network

针对D2D无线网络中多终端并发协作重传过程中平均解码时延较高的问题,提出了一种牺牲节点的协作重传策略。在重传阶段,发送终端在立即可解网络编码(Instantly Decodable Network Coding,IDNC)图上根据接收终端与发送终端的链路质量、终端数据包权重和接收终端的连通度选择出发送终端的最优编码包,以降低系统的平均解码时延。同时,利用部分接收终端对最优编码包的无效解码和不可解码的特性,扩展了备选协作终端,使更多的终端参与到协作传输过程。仿真结果表明,所提策略有效降低了系统的平均解码时延和重传次数。

In order to solve the problem of high average decoding delay in the process of multi-terminal concurrent cooperative retransmission in device-to-device(D2D)wireless network,a cooperative retransmission strategy at the expense of nodes is proposed.In the retransmission phase,the transmitting terminal selects the optimal coding packet of the transmitting terminal on the instantly decodable network coding(IDNC)diagram according to the link quality between the receiving terminal and the transmitting terminal,the terminal packet weight and the connectivity of the receiving terminal,so as to reduce the average decoding delay of the system.At the same time,taking advantage of the invalid decoding and undecodability of the optimal coding packet by some receiving terminals,the alternative cooperative terminals are extended to make more terminals participate in the cooperative transmission process.Simulation results show that the proposed strategy effectively reduces the average decoding delay and retransmission times of the system.