中文摘要：

随着无线通信技术的发展,车载自组织网络（Vehicular Ad Hoc Network,VANET）已经成为一个新型的研究领域。针对VANET中车辆行驶的特征以及车辆间安全信息传输严格的时延限制和高可靠性要求,提出了一种基于簇的协作MAC（CCB-MAC）协议用于安全信息的传输。当在广播期间节点没有接收到安全信息时,被选择的辅助节点重传先前侦听到的安全信息到目的节点,并且重传是在未被预留的时隙中进行的,这将不会中断正常的传输。数值分析和仿真结果表明,CCB-MAC明显提高了安全信息传输成功的概率,降低了传输时延和丢包率。

英文摘要：

Owing to the advancement of wireless communication technologies,vehicular Ad Hoc networks（VANETs）have become an emerging field of research.According to the characteristics of VANET and the strict delay constrains and high reliability requirement of safety messages,we presented a cooperative clustering-based MAC（CCB-MAC）protocol for safety messages.In CCB-MAC,the selected helpers relay the safety message to the nodes that have failed in reception during the broadcast period.In addition,cooperation is conducted in idle slots,without interrupting the normal transmission.Both numerical analysis and simulation results show that the proposed protocol improves the probability of successful packet transmission,reduces the transmission delay and packet loss rate significantly.