Simultaneously charging multiple sensor nodes in multi-antenna wireless-powered sensor networks

In this paper, we investigate a multi-node multi-antenna wireless-powered sensor networks (WPSN) comprised of one power beacon and multiple sensor nodes. The proposed beam-splitting technique enables a power beacon to split microwave energy beams towards multiple nodes for simultaneous charging. We propose an optimal joint beam-splitting and energy neutral control algorithm for perpetual operation of multiple sensor nodes. We have implemented a real WPSN testbed and conducted experiments. We have shown that the proposed algorithm can successfully keep all sensor nodes alive by optimally splitting energy beams to sensor nodes.