【摘要】 在分析考虑十字路口的广播协议的基础上,提出一种基于自适应信标交换的方向广播协议DB-IA。通过自适应信标交换机制获取网络拓扑信息,在各路段上选择最远节点转播分组,较大程度上减少广播跳数。采用ACK确认机制,结合双向传输和存储-转发策略缓解网络空洞造成的广播中断问题,提高广播的可靠性。通过设置递增的退避时间控制转播队列,使转播快速、有序完成。仿真结果表明,DB-IA具有相对较好且稳定的性能,适合交通安全类信息传输。更多还原

【Abstract】 A novel directional broadcast considering intersection via adaptive beaconing(DB-IA)based on the analysis of considering crossroads broadcast protocol was proposed.Adaptive beacon exchange mechanism was used to obtain the information of network topology,and node with the longest distance was selected to broadcast packet for each road,greatly reducing broadcast hop.DB-IA adopted acknowledgement(ACK)packets to ensure the reliability of broadcast.The combination of bi-directional propagation and carry-and-forward resolved the problem of network fragment.DB-IA controled the rebroadcast sequence by setting incremental backoff counter implicitly,in which way the relay nodes rebroadcasted in a timely and orderly fashion.Simulation results indicate that DB-IA performs better on effectiveness and reliability in different scenarios,which means it is suitable for traffic safety messages.更多还原