A Planar Integrated Beam Scanning Folded Reflectarray with Circular Polarization for Millimeter-Wave Applications

In this paper, a planar integrated circular polarization folded reflectarray (CPFRA) based on the single-layer thin substrate for spatial beamforming and wide-angle beam scanning is proposed. The substrate integrated waveguide (SIW) cavity-backed patch antennas are used as the primary feed sources instead of the conventional horn antenna. A meander line polarization converter is designed and integrated to achieve linear polarization to circular polarization conversion. A 140 mm × 140 mm CPFRA is simulated to verify this design. Simulated results show that the proposed CPFRA can achieve a 1.2 dB gain drop across the scanning convergence from _27° to 27° at the working frequency 26.5 GHz. The right-hand circular polarization (RHCP) beam is formed with the axial ratio (AR) less than 2 dB in the whole scanninz range.