All-Dielectric Huygens’ Metasurface Pair for mm-Wave Circularly-Polarized Beam-Forming

A novel all-dielectric Huygens' metasurface pair capable of circularly-polarized beam-forming is proposed. The proposed structure consists of two layers of dielectric resonators separated by approximately one quarter-wavelength at the design frequency. Each dielectric resonator is symmetrical to allow for the transmission of circularly-polarized waves. In order to physically design the structure, each resonator is connected to neighboring resonators using four symmetrical bridges. The second dielectric layer is added to cancel reflections caused by the bridges, allowing for the achievement of perfect matching. Fullwave simulations are used to demonstrate the full phase range achieved by varying unit cell dimensions. The operation of the proposed metasurface is further demonstrated by obtaining refracted and difference-pattern beams from a circularly-polarized slot array antenna.