Performance evaluation of uplink contention in visible light communications using road lamp

This paper provides a method to evaluate the performance of contention resolution process existing in the uplink visible light communications. In such a system, multiple vehicles share a common communication channel to convey data packets to receivers mounted in the road lamps along urban streets. A finite state Markov chain model is established to investigate the steady state probability distribution of the system. Then, the average number of vehicles and the average sojourn time of each vehicle are obtained. The model can be used to compare different back off policies. Simulation results are compared with the theoretic results given by the method to show the accuracy of the theory.