基于D2D的无线多媒体网络编码广播重传策略

Video distortion reduction with instantly decodable network coding and Device-to-Device communications

本文提出了一种基于Device-to-Device(D2D)的无线多媒体网络编码广播重传策略.在D2D场景下,多个终端设备之间存在网络编码冲突和传输冲突等问题.为此,构造了一种D2D广播网络编码(IDNC)图,所有的可行编码和无传输冲突情况均被表示在图中.基于构造的IDNC图,设计了面向批次传输和滑动窗口传输的最优广播重传算法.同时,为降低算法复杂度,提出了一种最大权重网络编码选择算法(MWSA-NC).仿真结果表明:与传统方案相比,提出的算法能极大地提高系统吞吐量,降低解码时延和减少视频流失真.

In this paper, we propose a scheme of wireless multimedia network coded broadcast retransmission, based on Device-to-Device （D2D） communications, in which there are network coding conflicts and transmission conflicts between multiple terminal devices. For this reason, a novel instantly decodable network coding （IDNC） graph is constructed, where all the feasible coding and non-transmission collision cases are shown in the graph. Based on the constructed IDNC graph, we design the optimal broadcast strategy for batch transmission and sliding window transmission, and propose a heuristic maximum weight network coding selection algorithm （MWSA-NC） to reduce the complexity of the optimal search algorithm. The simulation results show that compared to the traditional scheme, the proposed algorithm can greatly improve the throughput of the system, reduce decoding latency and reduce video stream distortion.