Multiple Antennas Design for the RF Wireless Power Transfer System

Wireless power transfer is a technology' that can effectively power various internet of things (IoT) devices that will explode in the future. Wireless power transmission is achieved through various methods, it is important to improve the power transmission distance and efficiency. In particular, long-range wireless power transmission system using microwave is less efficient than other transmission methods. Therefore, in designing the power transmitter and receiver, the link budget should be analyzed and the system should be designed based on this to maximize the power transmission efficiency. In this paper, we propose a multi-antenna design method of power transmitter and receiver via link budget analysis. Through the simulation and measurement results, it is confirmed that the antenna gain required in the system can be achieved through the multi-antenna configuration, and the optimal transmission power value should be calculated in consideration of the RF-DC rectifier efficiency. Based on this, it is possible to design a wireless power transmission system having excellent power transmission efficiency.