The Optimal Packets Scheduling for Buffer-Aid Energy Harvesting RSUs in Cooperative Vehicle Infrastructure System

Abstract

In this paper, we investigate the optimal packet scheduling for RSU-to-vehicle downlink communication in Cooperative Vehicle Infrastructure System (CVIS). The RSU is powered by a capacity-limited battery storing harvested energy with reliable energy source as backup, which meets requirement of renewable energy and ensures sustainability of communication system. We aim to find the optimal packet scheduling policy that minimizes the data queuing delay under a given the reliable power constraint and downlink availability rate. According to probabilistic scheduling policy, we adopt data buffer queue and harvesting energy queue as the state-space, and determine the transition action by the joint state of packet arrivals and channel state to establish a two-dimensional Markov chain. Based on this, the optimization problem is formulated. By solving the problem and analysing its solution, we derive the optimal transmission parameters and the optimal scheduling policy which turns out to be threshold-based. Simulations are demonstrated to verify the accuracy of the theoretical derivation results.