Electronically steerable antenna using a circular patch surrounded by a reconfigurable circular mushroom-like substrate

In this work, a novel technique for designing electronically steerable antennas by using a circular patch incorporated with a reconfigurable mushroom-like substrate has been proposed. The mushroom-like substrate is composed of a periodic structure of metallic rings and of a periodic structure of vias. The beam steering is obtained by controlling the connection of the vias to the ground. The gain, beam direction and return loss have been analyzed for different configurations using a full-wave method. These results show that the proposed antenna is able to steer a beam in two planes with a more than 10 dB gain. Experimental results have been presented to validate the proposed concept.