Linear-to-circular polarization conversion based on all-dielectric 3D-printed metasurface for the application of broadband circularly polarized reflectarray antenna

A form of reflective half-wave plate based on all-dielectric 3D-printed metasurface is proposed in this paper. The element of the proposed reflective half-wave plate consists of a novel hexagonal prism dielectric resonator (HPDR), a square substrate and a ground plane. The designed HPDR element can effectively convert the incident linearly polarized (LP) waves into the reflected circularly polarized (CP) waves. Meanwhile, an approximately linear reflection phase ranging over 360 degrees of HPDR element is realized by varying the height of HPDR, which can significantly simplify the design procedure. In addition, based on the proposed HPDR element, a CP dielectric reflectarray antenna is designed. In order to verify the feasibility of the proposed design method, the dielectric reflectarray antenna with LP feeding is fabricated and measured, which can achieve a 1 dB gain bandwidth of 17.9% and a 3 dB axial-ratio bandwidth of 15%. A good agreement between the simulation and measurement is also observed. To the best of authors' knowledge, the broadband CP dielectric reflectarray antenna based on all-dielectric 3D-printed metasurface may be the first ever reported.