Node Failure Avoidance Mobile Charging in Wireless Rechargeable Sensor Networks

Abstract

Recent breakthrough progress of wireless energy transfer technology and rechargeable lithium battery technology emerge the wireless rechargeable sensor networks(WRSNs). In WRSNs, how to schedule the mobile charger to efficiently replenish energy for sensor nodes is very challenging. However, most of current existing WRSNs mobile energy replenishment schemes either cannot adapt to the dynamic and diversity energy consumption of sensors in actual environment or leave out of consideration of the fairness of charging response, which may result in sensor nodes failure due to energy depletion and low charging performance. Particularly, the nodes failure issue will get worse when there are a large number of charging requirements in the network. In this paper, we explore the node energy depletion problem in mobile charging for WRSNs and propose a node failure avoidance online charging scheme(NFAOC). To avoid the nodes failure due to energy depletion, NFAOC compares the current maximum tolerable charging delay of each request node with its shortest waiting time for charging, and then always chooses the nodes which make the least number of other request nodes suffer from energy depletion as the charging candidates. Simulation results demonstrate that NFAOC can effectively solve the node energy depletion problem with lower charging latency and charging cost in comparison with other current existing online charging schemes.