60GHz 2D metal-only reflectarray with high gain and high aperture efficiency

A metal-only reflectarray with a feed aperture is simulated to obtain high gain and high aperture efficiency. The optimal aperture height of a feed is approximately the height of a reflectarray. Using this optimal aperture height (= 80 [mm]), we obtained the simulated antenna gain as 35.1 [dB] for 60 [GHz]. To understand the E-plane radiation pattern of a metal-only reflectarray, we formulated the electric field of a feed aperture and adopted the physical optics (PO) approximation.