A Periodic and Distributed Energy Supplement Method Based on Maximum Recharging Benefit in Sensor Networks

The issue of using vehicles to wirelessly recharge nodes for energy supplement in wireless sensor networks has become a research hotspot in recent works. Unfortunately, most of the researches did not consider the rationality of the recharging request threshold (RRT) and also overlooked the difference of node's power consumption, which may lead to the premature death of nodes as well as low efficiency of wireless charging vehicles (WCVs). In order to solve the above problems, a periodic and distributed energy supplement method based on maximum recharging benefit (PDESM) is proposed in this article. First, to avoid frequent recharging requests from nodes, we put forward an annuluses-based cost-balanced data uploading strategy under deterministic deployment. Then, one WCV in each annulus periodically selects and recharges nodes located in this region which sends the energy supplement requests. In addition, the predicted values of power consumption of nodes are calculated out according to the real-time energy consumption rate, and thus the most appropriate RRT is obtained. Finally, a moving path optimization scheme based on the minimum spanning tree is constructed for distributed recharging. Simulation results show that PDESM performs well on enhancing the proportion of the alive nodes as well as the wireless recharging efficiency compared with node failure avoidance online charging and first come first served. Moreover, it also has an advantage in balancing the energy consumption of WCVs.