MAC Performance Analysis for Vehicle-to-Infrastructure Communication

The newly emerged vehicular ad hoc network adopts the contention based IEEE 802.11 DCF as its MAC. While it has been extensively studied in the stationary indoor environment (e.g., WLAN), the performance of DCF in the highly mobile vehicular environment is still unclear. On addressing this issue, we propose a simple but accurate analytical model to evaluate the throughput performance of DCF in the high speed vehicle-to-infrastructure (V2I) communications. We unveil the impacts of nodes mobility (velocity and moving directions) on the system throughput. Particularly, we show that with node velocity increasing, the throughput of DCF decreases monotonically, which demonstrates the inefficiency of DCF in the highly mobile environment. Via extensive simulations, we validate the accuracy of the developed analytical model and finally discuss the method to optimize DCF towards the maximal throughput.