High gain transmitarray antenna based on ultra-thin metasurface

This article presents a bandwidth enhanced transmitarray (TA) antenna based on ultra-thin metasurface (MS) for high gain operating at X-band. The antenna consists of a three layers continuous flat structure and an aperture coupled microstrip antenna as the feed source. The relative phase shift of 360° is achieved by the unit cell design based on ultra-thin MS, and the quasi-spherical wave could be focused as plane wave when the wave goes through TA. The aperture coupled microstrip feed is designed with a bandwidth of 20.6%, and the bandwidth enhanced property of feed source will reduce the negative effect of elements mutual coupling on TA and increase the bandwidth of the TA antenna. The TA antenna gain increases from 8.25 to 18.98 dB and with a side lobe level of −14.3 dB. Owing to the low-profile and easy configuration, this kind of TA antenna has great potential, wireless communication.