Demonstration of Auto-Tracking Charging for a Smartphone with Microwave Power Transmission and Qi Wireless Charging

This paper demonstrated a tracking charging system for a free-moving smartphone, which utilized image recognition technology to locate the position of the smartphone, using a 5.75 GHz phased array system to shift the microwave beams toward the smartphone, then a microwave rectifier circuit converted microwave power into dc power to supply the Qi wireless charging circuit for charging the smartphone. The maximum transmission power of the phased array is 32W, and the radiation angle of the microwave beam is within +/- 25 degrees when the smartphone is outside the radiation area the transmission power will be stopped. The transmission distance is within 50cm, and the smartphone can be automatically tracked and charged.