Demo: Design and Implementation of Intelligent Reflecting Surface for Microwave Power Transmission

Intelligent Reflecting Surface (IRS) is attracting attention as one of the wireless communication technologies that will realize Beyond 5G/6G. IRS is a plate-like device that can reflect incident radio waves by arbitrarily changing their phase for beamforming. In this paper, we design and implement a prototype of IRS for use in microwave wireless power transmission, which is expected to be a means of powering IoT devices and drones. This prototype is composed of 25 reflective elements, each comprising a dipole antenna and varicap diodes. It can set any reflection phase in the range from 0 to π. In the demonstration, we show how the received power can be improved by controlling the reflection phase of each reflective element of IRS by placing it between a wireless transmitter and a receiver.