Offset reflectarray using single-layer microstrip elements with high metallic conductor areas

In this paper, an offset reflectarray with single-layered microstrip elements whose metallic conductor areas are high, which can achieve an improved aperture efficiency of an offset reflectarray antenna. The elements consist of rectangular sub-patches which are divided by patch division lines (PDLs) and the reflection phases are not obtained by varying metallic conductor size but only by moving PDLs. To show a validation of the proposed elements, an offset reflectarray is fabricated and analyzed at 12 GHz. The realized gain of the offset reflectarray antenna is 28.19 dBi with aperture efficiency of 62%, where the diameter of the reflectarray is 260 mm with focal length of 190 mm.