Opportunistic vehicle-to-vehicle relay with adaptive modulation for drive-thru internet access

Drive-thru Internet is a promising technique that exploits the inter-connected roadside access points (APs) to offer Internet access. However, there will be very high costs to deploy and maintain a large number of APs to provide ubiquitous coverage. There are many studies on vehicle-to-vehicle (V2V) relay to further improve the performance of the drive-thru Internet system. In this paper, we investigate an opportunistic V2V relay protocol with adaptive modulation and propose an analytical approach to evaluate the access performance in terms of average packet delay and overall success probability. Based on the analysis, the modulation modes can be adapted to guarantee a required transmission success probability while minimizing the average packet delay. The numerical and simulation results demonstrate the accuracy of the analysis and the effectiveness of the proposed V2V relay protocol with adaptive modulation.