A Wideband Wide-Beam Microstrip Antenna with Superstrate for Millimeter-Wave Applications

Antennas’ wide beamwidth is necessary for wide area coverage. This paper presents a wideband millimeter-wave microstrip antenna featuring half-power beamwidths (HPBWs) of 131° and 125° in the E- and H-planes. It comprises a circular patch, two back-to-back half-disks, and two concentric metallic ring strips on a superstrate. A slot on the ground fed by a microstrip line acts as the antenna’s excitation. Simulation results show that the antenna’s bandwidth is enhanced by the compound notches on the half-disks, and the beamwidth is increased by the two concentric metallic rings on a superstrate. Being optimized, the proposed wide-beam antenna demonstrates an impedance bandwidth of 54% that ranges from 22.23 GHz to 38.7 GHz, which makes the antenna an excellent choice for communications systems or phased arrays.