W-Band Folded Reflectarray Using Elements with Polarization Torsion

This paper presents a novel W-band folded reflectarray antenna composed of a single-layer reflectarray, a polarizing grid, and a linearly polarized horn feed. It features a unique element with polarization torsion, consisting of two copper layers on a Rogers RT5880 substrate. Using this element, a square reflectarray with an aperture diameter of 11.
$99\lambda 0(39.1$
mm) at a center frequency of 92 GHz was designed and analyzed. The simulation results show a gain of 28.7 dBi at 92 GHz and a maximum aperture efficiency of 49.5%. Additionally, the proposed antenna exhibits a 1-dB gain bandwidth of 10.87% (88–98 GHz) within the W-band. These findings highlight the promising potential of this design for wireless communication applications.