Abstract: In order to solve the problem of real-time charging of nodes in a large wireless rechargeable sensor network, a network with multiple mobile chargers is studied. Based on the fair division of the network into multiple clusters, a real-time charging algorithm for multiple mobile chargers (STMA) based on space-time cooperation is proposed: the charging path of the mobile charger is planned by jointly considering the spatial location of the node and the charging deadline. The latest charging request is obtained in time during the charging process, and the charging path is adjusted in time according to the urgency of the charging request. The simulation results show that, compared with the algorithm that simply considers the space-time requirements, the STMA algorithm increases the energy utilization rate by about 14% and the node survival rate by about 9%, which is more suitable for the real-time charging requirements of the nodes. 

Key words: wireless rechargeable sensor network, multiple mobile-chargers, real-time charging, space-time collaboration