基于位置信息的多车协同碰撞预警协议

在车载自组网中,无线信道的通信质量直接影响了EWM(emergence warning message)的多跳广播传输性能.为提高车辆在复杂信道环境下的EWM传输效率、降低延时,综合考虑交通环境下无线网络信号的可靠性、消息传输的实时性及道路交通状况信息,提出一种基于位置信息的多车协同碰撞预警协议(vehicle collision warning protocol,VCWP).该协议在通信范围内选取首选转发车和候选转发车,在进行退避时间的选取时,采取基于邻节点密度的信道竞争机制,以保证EWM在复杂信道环境下的低时延、可靠送达.仿真验证表明VCWP与GPSR(greedy perimeter stateless routing)、IEEE 802.11p协议的BEB(binary exponential back-off)退避策略相比具有良好的性能,提高了EWM传输成功率,降低了时延,为复杂信道通信质量环境下EWM的传输提供了可靠性保证.

Research on Multi-Vehicle Cooperative Collision Warning Protocol Based on Location Information

In vehicular ad hoc networks (VANET), the communication quality of wireless channel directly affects the performance of EWM (Emergence Warning Message) multi-hop broadcast. In order to improve the EWM transmission efficiency and reduce the delay of vehicles in the complex channel environment, a multi-vehicle collision cooperative early warning protocol(VCWP) based on location information is proposed, which comprehensively considers the reliability of wireless network signals, real-time transmission of messages and road traffic condition information in the traffic environment. The protocol selects the preferred forwarding vehicle and the candidate forwarding vehicle within the communication range to ensure the low delay and reliable delivery of EWM in the complex channel environment. In the selection of retreat time, the channel competition mechanism based on the density of adjacent nodes is adopted. Simulation results show that VCWP has good performance compared with GPSR(Greedy Perimeter Stateless Routing) and BEB (Binary Exponential Back-off) based on IEEE 802.11p, improves the success rate of EWM transmission, reduces the time delay, and provides a reliability guarantee for EWM transmission in complex channel communication quality environment.