城市环境下VANET路由协议的研究.docVIP

 城市环境下 VANET 路由协议的研究 雷亚星，李剑峰** （北京邮电大学信息与通信工程学院，北京 100876） 5 10 15 20 25 30 摘要：在城市环境下，由于车载自组织网络（Vehicular Ad Hoc Network，VANET）拓扑结 构复杂、变化快，车辆节点移动速度较高，车辆运动轨迹受限于道路静态形状等特点，给 VANET 路由协议的设计带来了很大困难。本文提出了一种改进 VANET 路由协议—基于辅助转 发中心（Auxiliary forwarding center，AFC）的路由算法，即在路口设置辅助转发中心， 用来弥补移动节点转发数据包时，在路口位置容易产生数据分组转发中断的缺陷。本文采用 网络仿真软件 NS2（Network Simulator Version 2）对理论研究成果进行仿真。通过对比 分析 AFC 网络和无 AFC 网络数据传输性能，仿真结果表明：借助于路口设置的 AFC，减少了 数据包由于路口转发失败导致丢包的现象，在保证端到端时延的情况下提高了数据包的交付 率。因此，在车载自组织网络中，本文研究的算法可以提供更好的网络性能。 关键词：车载自组网；地理位置信息；AFC 中图分类号：TP393/H32 THE RESEARCH OF VANET ROUTING PROTOCOL IN CITY SCENARIOS LEI Yaxing, LI Jianfeng (School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876) Abstract: In the urban environment, these three reasons：high-speed of the vehicles, complexity and quickly-changed the topology of the VANET, and the trajectory of Vehicle movement limited by the road static shape , introduce much difficulties to design of VANET routing protocols. An improved VANET protocol – Routing Protocols based on Auxiliary forwarding center, was proposed in this paper. It is realized by setting Auxiliary forwarding center in the intersection, to solve the problem that the data packet transmissions easy to be interrupt. In this paper, the network simulator NS2 is used to evaluate the research findings. By comparing the data transmission performance between AFC set in the intersection or not, the modified VANET protocols show better data transmission performance. By helping of AFC set in the intersection, less data packet failed. Therefore, the improvement of the two parts raised data packet delivery on condition that the end-to-end delay has not been increased. Consequently, in VANET, the proposed protocol in this paper can provide a better performance. Keywords: Vehicular Ad hoc Network; geography; AFC 35 0 引言 由于 VANET 中所有节点地位平等、自组织、无需事先布置网络设施或者中心控制节点、 网络节点高速移动导致网络拓扑动态变化等，路由算法在很大程度上决定了整个 VANET 网 络的性能。因此，如何设计出有效的路由