Warning Data Dissemination Technology Research Based On 802.11 Broadcast For Vehicular Networks

With the development of wireless communication technologies, there are more and more vehicles equipped with wireless communication instruments. Then wireless communication among vehicles and between vehicles and roadside infrastructure appear. Wireless communication among vehicles is similar to ad hoc networks, thus, it is also called as VANETs. Otherwise among vehicles is not entirely equal to ad hoc networks. Especially, broadcast technology in the ad hoc networks not adapt to warning message broadcasting in the VANETs.Safe application is the most important among the applications of the VANETs. Thus, this paper thoroughly discusses warning data dissemination in the VANETs.First, this paper introduces broadcast technology in the ad hoc networks and the standard of dedicated short range communication (DSRC) and analyzes the demand of warning data dissemination in the VANETs.Second, single-hop can meet to the demand of warning data dissemination while scope of accident is small. According to the fact, the paper proposed a strategy of adaptive warning data dissemination on the basis of summarizing the newest technology. The strategy can enhances reliability and reduce delay of warning data packets.Finally, the paper analyzes the collision problem of rebroadcast that exists in the environment of forwarding warning data based on multi-hop. On the basis of the foregoing analysis, the paper proposed a strategy of warning data dissemination that based on 802.11 broadcast in the VANETs. Packet forwarding time of the strategy changes adaptively with local node density in the VANETs. Simulation results show that the strategy can reduce packet forwarding the delay time.