Wireless Energy Transmission Channel Modeling in Resonant Beam Charging for IoT Devices
Power supply for Internet of Things (IoT) devices is one of the bottlenecks in IoT development. To provide perpetual power supply for IoT devices, resonant beam charging (RBC) is a promising safe, long-range, and high-power wireless power transfer solution. How long distance RBC can reach and how much power RBC can transfer? In this paper, we analyze the consistent and steady operational conditions of the RBC system, which determine the maximum power transmission distance. Then, we study the power transmission efficiency within the operational distance, which determines the deliverable power through the RBC energy transmission channel. Based on the theoretical model of the wireless energy transmission channel, we establish a testbed. According to the experimental measurement, we validate our theoretical model. The experiments verify that the output electrical power at the RBC receiver can be up to 2 W. The maximum energy transmission distance is 2.6 m. Both the experimental and theoretical performance of the RBC system are evaluated in terms of the transmission distance, the transmission efficiency, and the output electrical power. Our theoretical model and experimental testbed lead to the guidelines for the RBC system design and implementation in practice.