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在车载网络VANETs(Vehicle Ad Hoc Networks)中,采用广播技术分发数据包.为此,提出基于概率和时延的混合的车载网络广播PDHB(Probabilistic and Delay-based Hybrid Broadcast)协议.PDHB协议主要由转发概率计算阶段和定时时延2个阶段.首先,利用车辆密度和距离信息计算转发概率,然后再利用转发概率设置定时,进而减少冗余数据包,缓解广播风暴问题.仿真结果表明,与泛洪广播协议相比,PDHB协议的冗余数据包下降近20％,数据包投递成功率提高了23％.“,”Broadcasting is used in data dissemination for Vehicle Ad Hoc Networks (VANETs). Therefore, a probabilistic and delay-based hybrid broadcast (PDHB) protocol for VANETs is proposed in this paper. PDHB protocol is characterized by two phases: probability-computing and delay-timing. Firstly, the density and distance of vehicles are used to compute the probability of forwarding messages, then the time interval of delay is decided according to the probability, which reduces numbers of redundant messages and copes with the broadcast storm problem. The simulation results show that the proposed protocol reduces redundant messages. Compared with flooding, numbers of redundant messages of PDHB is reduced by 20 ％, and the data deliver ratio is improved by 23 ％.