2D leaky-wave antenna with controlled direction of radiation in the azimuthal plane

This paper presents a two-dimensional (2D) metasurface antenna array composed of mushroom cells coupled by thin slots in the top metallization. The antenna is fed through power dividers designed in substrate-integrated waveguide technology. The antenna structure is therefore designed in a fully up-to-date integrated version. The array shows beam steering in the azimuthal plane controlled by signal amplitudes fed into particular ports at the edges of the matrix. The main advantage of this antenna is no need to use phase shifters applied in standard 2D antenna arrays. Two antenna versions have been designed, fabricated, and experimentally tested. The beam can be steered within 360 degrees (90 degrees) in azimuth. The steering of the beam in elevation from backward to forward directions within 40 degrees is done by changing frequency from 21 up to 23.8 GHz. This interval is reduced to 30 degrees by exciting the antenna simultaneously at two adjacent ports at the same amplitude.