Multi-Hop RF Wireless Power Transfer for Autonomous Wireless Sensor Network

This paper is devoted to studying multi-hop wireless power transfer (WPT), which is especially applicable in autonomous wireless sensor networks. The main objective of the current work is to investigate the possibility of increasing the efficiency of WPT using a multi-hop transmission approach. The study describes the main limitations of the multi-hop RF energy transmission, analyses the possible technical solution of a multi-hop sensor node, and evaluates the performance of multi-hop WPT compared to the classical technique. The research combines RF signal transmission simulations and experimental studies. Multi-hop WPT analysis is made for the sub-GHz frequency band and two wireless nodes. Friis approximation of point-to-point signal propagation is used for simulating the multi-hop energy transmission in free space, while the method of Shooting and Bouncing Ray is used for multichannel propagation simulation. Current work expands the WPT applications by providing an approach to increase the distance of RF energy transmission for the wireless sensor nodes in the areas with lower coverage.