Comprehensive GPSR Routing in VANET Communications with Adaptive Beacon Interval
Traditional GPSR and its enhanced protocols make forwarding decision only basing on one specific segment of the neighborhoods, thus the Successful Date Rate (SDR) often seems unpleasing. And the constant beacon interval always cause data collisions when the vehicle densities meet a high level. To solve the problems, we introduce a concept - the Coefficient of Dependence (CoD), to describe the contribution of all the influencing factors within two-hops, where the CoD is synthetically considered according to its neighbors' number, data deliver frequency, driving direction and positions. The beacon interval is then set dynamically by CoD. Besides, we propose the synthetical Optimum in Optimums (OinO) strategy when node is to forward packets, ensuring the worst result barely acceptable. The simulation results confirm that our scheme reduces beacon overhead and data collisions especially in high densities and velocities of vehicular ad hoc network, while ensuring the Successful Date Rate (SDR) performances well.