Continuously Beam-Steered Phased Array Antenna Using GaN Varactors for Millimeter-Wave Applications

A continuously steerable beam patch antenna array employing a classical phase shifter based on GaN HEMTs is presented. Here, the GaN HEMTs are used as varactor diodes to achieve the tunability purpose. By controlling the DC bias of these varactors from −2 V to 2 V, the proposed array antenna can provide continuous beam steering from 0° to +25° in the azimuth plane at 41.20 GHz, while achieving a low side-lobe level and good impedance matching performances. Using GaN HEMTs as varactors to achieve beam steering capability has never been tried before to the best of our knowledge. The measurement results agree well with the simulation results and validate the effectiveness of the proposed beam steering based on GaN technology. This proposed phased array antenna will find numerous applications within future wireless communications systems, especially for millimeter-wave applications.