The Research Of Routing Algorithms For Vehicular Ad-hoc Networks In The Multiple Scenarios

With the rapid development of national economy, the vehicle plays more and more important role in daily life. As traffic developes, it also becomes a severe problem which obesses people. The frequent accidents, serious traffic congestion and complex terrain environment and the comfort of travelling environment and other issues are attracting increasing attention. So how to deal with the problems faced by daily traffic to improve traffic safety and comfort is an important issue which relates to the social harmony and economic development.As mobile Ad-Hoc network technology continues to mature in recent years, many researchers has begun to deploy the mobile Ad-Hoc network in the automotive environment to solve the traffic problems faced by daily traffic.Based on highways and city scenes as the background this paper carries out a series of studies about the routing layer in vehicular Ad-Hoc networks and puts forward some innovative algorithms which are validated by the mobile model of vehicles in actual environment.Firstly: At the scene of highway through the new method of setting CBF timer the improved algorithm CBF-MA can actively sense the vehicular speed and direction of movement, thus it can choose the next node more suited as a forwarding node to reduce routing hops and shorten the delay in transmitting data packets to destinations. PCBF-MA algorithm is the further expansion of CBF-MA algorithm. In addition to sensing nodes'speed and direction of movement it also can predict the distance between vehicular nodes based on the speed and direction of corresponding nodes and thereby further reducing of the number of broadcast data packets and the pressure on the wireless bandwidth.Secondly: In the city scenes the algorithm of PCBF-MA based on the anchorpath is a improvement of PCBF-MA algorithm according to the characteristics of complex topography of city scenes and the traffic flow on roads. The selection process of anchorpath can record the corresponding road information. In this way this process can initiatively sense the terrain in urban scenes to avoid routing failures caused by obstructions as well as can also sense the density of traffic on the city roads to avoid routing failures caused by bad network connectivity.The last part of this paper proves the feasibility of the improved CBF algorithms put forwarded in this paper through a series of simulation experiments. Whether in the highway scene or scenes in the urban environment, CBF-MA algorithm, PCBF-MA algorithm and based Anchor-path PCBF-MA algorithm have shown good performance.