A Dual-Circularly Polarized Reconfigurable Reflectarray Antenna With Independent Beam Scanning Capability

A 1-bit reconfigurable reflectarray antenna (RRA) capable of simultaneously radiating left-handed circular polarization (LHCP) and right-handed circular polarization (RHCP) beams is proposed in this article. Furthermore, the LHCP and RHCP beams can be scanned independently. A polarization decomposition and synthesis method is utilized to transform the dual-circularly polarized (dual-CP) phase control into equivalent dual-linearly polarized (dual-LP) phase control. Using this method, an RRA element with a combined cross and split-ring shape is designed. Four PIN diodes are soldered on the element. By switching the diodes, four states are realized to independently control the dual-CP phase response. An array consisting of
$16 \times $
proposed elements is fabricated and measured. The results show that the array operates near 16.5 GHz and can independently scan dual-CP beams from 0° to 45°. The maximum gains for LHCP and RHCP beams are 19.22 and 18.72 dBic. The 3-dB gain bandwidth and 3-dB axial ratio bandwidth are 6.1% and 4.9%, respectively.