A focusing reflectarray and its application in microwave virus sanitizer

In this paper, a focusing reflectarray based on the conductor-backed strip dipole unit cell is proposed and designed for use in the microwave virus sanitizer. Unlike traditional far-field antennas that form a planar phase front in a specified far-field direction, the focusing reflectarray is designed to coherently add the fields radiated from the feeding antenna at a predetermined focal point, typically within its radiating near-field region and to ensure adequate power density to inactivate the H3N2 virus sample. Furthermore, the focusing reflectarray has a simple and planar structure compared with conventional focusing antennas. Since the microwave resonant absorption frequency of the H3N2 virus is at about 8GHz, an 8x8 focusing reflectarray is designed for operation at 8GHz. A prototype antenna is then fabricated and used for H3N2 virus sanitization. It is demonstrated experimentally that the death rate of the H3N2 virus sample is up to 93%, verifying the feasibility of the microwave virus sanitizer as well as the proposed focusing reflectarray.