Delay-Tolerant On-Demand Mobile Charging Scheduling Scheme for Wireless Rechargeable Sensor Networks

Wireless sensor networks based on mobile charging vehicle can significantly alleviate the problem of network energy hole and extend network lifetime, but it is faced with how to improve the charging efficiency when the charger's power is constant. In this paper, a delay-tolerant on-demand mobile charging scheduling scheme (DMCSS) is proposed for maximizing the the charging efficiency and preventing nodes from premature failure under the condition of limited mobile charger capacity. The main challenges of our scheme are how to optimize the trajectory and maximize charging efficiency. In DMCSS, we design an adaptive and scalable energy charging strategy for realizing the rational allocation of power resource and devise an efficient next charging node selection algorithm function by considering the angle, the residual energy of RS and the current distance between request RS and MCV. With extensive simulations, we demonstrate that DMCSS scheme not only significantly increases charing efficiency, compared with EDF, NJNP, LADP, and RCSS schemes, but also prevents nodes from premature failure.