Coverage-Aware Recharging Scheduling Using Mobile Charger in Wireless Sensor Networks

Energy recharging in wireless rechargeable sensor networks (WRSNs) has acquired much attention in recent years. In literature, many recharging path construction algorithms have been proposed. Most of them considered that all sensors are equally important and designed algorithms to increase the number of recharged sensors or decrease the path length of the mobile charger. However, different sensors have different coverage contributions. Recharging the sensors with larger coverage contribution can achieve better surveillance quality. The proposed recharging scheduling algorithm is divided into three phases, including the <italic>Initialization</italic>, <italic>Recharging Scheduling and Path Construction Phases</italic>. In the second phase, this paper proposed two recharging scheduling algorithms, namely the <italic>Cost-Effective</italic> (<italic>CE</italic>) <italic>algorithm</italic> and <italic>Cost-Effective with Considerations of Coverage and Fairness</italic> (<inline-formula> <tex-math notation="LaTeX">$C^{2}F$ </tex-math></inline-formula>) <italic>algorithm</italic>. The proposed two algorithms construct paths for the mobile charger and select the recharging sensors based on the higher weight in terms of larger coverage contribution and smaller path cost. Performance results show that the <italic>CE</italic> and <inline-formula> <tex-math notation="LaTeX">$C^{2}F$ </tex-math></inline-formula> algorithms yield better performance in terms of the fairness of recharging, recharging stability and coverage ratio, as compared with the existing studies.