城市车联网中紧急消息的快速广播路由研究

On Fast Broadcasting of Emergency Messages in Urban VANET

研究了车载自组织网络(VANET)中紧急安全消息的多跳广播协议,针对城市场景的特点提出了一种基于最小期望剩余时延转发的广播算法(BP-MEDF).该算法综合考虑了信号衰落、排队时延、广播干扰和车辆快速移动等因素,提出基于最小期望剩余时延的中继优选模型,结合城市道路的静态和动态路由属性,协议规定发送端首先指定最佳中继快速转发消息,当指定的中继转发失败时其他接收节点协作转发以确保路由可靠性.通过NS2仿真表明,相比于传统的协议, BP-MEDF在满足一定广播可靠性的前提下,降低了广播时延,具有更高的广播效率.

This paper is related to the studies on multi-hop broadcast protocols for safety message in Vehicular ad-hoc Network(VANET), and a broadcast protocol has been proposed with the minimum expected delay forwarding(BP-MEDF) in city scenario. Considering such factors as signal fading, queuing delay, broadcast interference and rapid movement of vehicles etc. BP-MEDF presents relay optimal selection model based on the minimum expected delay forwarding, and combine the Static and dynamic routing properties of urban road to forward message as the best forwarder at sending end, and other receivers assist in forwarding if specified forwarder rebroadcasts unsuccessfully. The software simulation shows that BP-MEDF reduces the broadcast delay on the premise of satisfying the broadcast reliability comparing with the traditional protocol.