2-Dimensional (2D) Beam Steering-Antenna Using Active PRS for 5G Applications

This paper presents a compact coaxial-fed square microstrip patch antenna integrated with a beam-steering Partially Reflective Surface (PRS). The proposed design has a two-dimensional (2-D) Fabry-Perot Cavity (FPC) antenna acting as a radiator and the PRS as a beam-steering superstrate operating at 5.5 GHz. The PRS consists of 6 × 6 reconfigurable unit cells etched on Rogers 5880 with a thickness of 1.57 mm. By controlling the switching of PIN diodes in different sections of PRS, beam steering can be achieved up to ±47° in the azimuth plane with a gain of 9.1 dB and 10.2 dB and ± 15° steering in an elevation plane with a measured gain of 9.3 dB and 8.9 dB, respectively. The antenna prototype is 2.56 λ × 2.56 λ at 5.5 GHz, and the measured gain values are around 10 dBi for all the states. The beam is able to radiate at boresight or tilted to 42° in two azimuthal directions and 45° in elevation direction by adjusting the PIN diodes ON/OFF states. The 10 dB impedance bandwidth of 5.4–5.52 GHz is achieved.