Research On Charging Scheduling Optimization Of Rechargeable Sensor Networks

For a long time,wireless sensor networks have been constrained by the energy bottleneck problem,and wireless power transmission technology provides a new way to solve the energy bottleneck problem,which leads to Wireless Rechargeable Sensor Networks(WRSNs).In WRSNs,the performance of charging scheduling algorithm significantly affects the energy supply efficiency and network lifetime of WRSNs,which is the key factor to maintain the long-term operation of WRSNs.This paper takes the mobile chargers'scheduling strategy in WRSNs as the main research object,mainly including the following 3 aspects:(1)In the single mobile charger scheduling scenario,a scheduling algorithm for customizing charging method called PartialCharge is proposed.In the PartialCharge algorithm,we first select a set of core nodes that can guarantee the coverage of the network monitoring points and provide full charging services for them.When the charging request queue is not schedulable,PartialCharge selects some non-core nodes to provide partial charging services,and deletes the non-core nodes with excessive overhead from the queue.The simulation results showed that the charging throughput,waiting queue length,average response time and node survival rate of the PartialCharge algorithm was improved compared with the existing classical scheduling algorithm.(2)We propose a comprehensive scheme to extend the network lifetime by combining reducing charging task redundancy and optimizing charging scheduling.The scheme includes a sleep scheduling algorithm(K-covering Redundant Node Dormant Scheduling Algorithm,KRND)and a collaborative multi-charger scheduling algorithm(Multi Charging WCV Distance&Energy Oriented Scheduling Algorithm,MCDE).KRND algorithm can determine redundant nodes efficiently by studying the coverage of node sensing boundary and set a node sleep scheduling scheme to ensure the energy balance of nodes.MCDE algorithm defines an effective charging negotiation protocol between nodes and mobile chargers,which can effectively avoid vicious competition among mobile chargers and reduce energy waste.The simulation results showed that our scheme had an obvious improvement in energy saving and charging efficiency compared with the traditional methods.(3)We propose a network partition-based multi-charger scheduling method.In this method,a partition algorithm(Multi-WCV Region Partition Charging Scheduling Algorithm.MPSA)considering the differences of nodes is proposed.The MPSA algorithm not only reduces the charge scheduling complexity of the mobile charger in each zone,but also provides convenience for improving the energy guarantee level of the core nodes.Our method also designs a charging scheduling algorithm(Low Cost Charging Scheduling Algorithm within Each Partition,LCP)to promote the charging efficiency of a mobile charger in each network partition.The simulation results showed that compared with the traditional methods,the MPSA algorithm could effectively reduce the loss caused by node failure,and the LCP algorithm could effectively improve the charging efficiency of the mobile chargers.