基于网络编码的优化V2R数据传输性能的研究

Research on V2R data transmission performance optimization based on network coding

将路侧设备RSUs作为车载网络VANETs的缓冲点,可缓解车与车V2V之间连通的间歇性问题。然而,由于车辆的快速移动以及RSU短的传输距离,车辆驻留同一个RSU的时间很短。尽管广播技术能够有效地提高广播带宽利用率以及系统响应时间。但RSU采用广播技术前需要获取车辆缓存数据项的先验知识。因此,车辆需要向RSU服务器上传缓存信息,浪费了带宽。为此,针对基于RSUs的VANETs,提出基于网络编码的车与路边设施V2R通信的数据传输算法NCDD。NCDD算法允许车辆不必向RSU服务器上传它们的缓冲信息,并利用网络编码提高RSU的广播性能,仿真结果也证实了NCDD算法能够有效地降低截止期错失率和系统响应时间。

The road side units(RSUs)acting as a buffer point of VANETs(vehicular Ad Hoc networks)can alleviate the intermittent connectivity issue of vehicle-to-vehicle(V2V). The vehicle spends short time on stopping at the same RSU due to the fast vehicle mobility and short RSU transmission range. Although the broadcast technology can improve the broadcast bandwidth usage efficiency and system response time effectively,but the RSU before using broadcast technology needs to acquire the prior knowledge of vehicle′s cached data items. Therefore,the vehicle needs to upload the cache information to the RSU server,which wastes the bandwidth. Aiming at VANETs based on RSUs,a network coding-based data dissemination(NCDD)algorithm of V2 R is proposed. The NCDD algorithm allows vehicles not to upload their cache information to RSU server. The network coding is used to improve the RSU broadcast performance. The simulation results verify that the NCDD algorithm can reduce the deadline miss ratio and system response time.