Charging Scheduling Algorithm for Wireless-Powered Communication Networks

Abstract

Wireless power transfer (WPT) to charge a wireless device (WD) using radio frequency (RF) has been a promising power supply solution in wireless networks. It should extend network lifetime and guarantee network sustainability and reliability. Charging from one energy source (ES) shared by several WDs makes the scheduling algorithm most important. This paper considers a directional ES that has significant scheduling impacts relative to the more commonly studied omnidirectional ES. The directional energy source overcomes the restrictions of broadcast energy by concentrating the power on the intended sectors and thus significantly improving energy efficiency. We propose a charging scheduling algorithm to maximize the network lifetime under several network conditions. The proposed algorithm first determines the charging duration for all WDs in a given sector. The algorithm then determines the transmit power from ES to each WD in the sector. The performance of the proposed algorithm is compared with that of a well-established benchmark scheme. The extensive simulation results demonstrate the effectiveness of our proposed algorithm.