2025 Volume E108.B Issue 3 Pages 274-281
A reflector antenna excited by TM01 circular waveguide mode is studied. Since the conventional reflector antenna with steps cancels out half of the polarized components in the main beam direction, the polarization loss increases, theoretically by 3 dB. Therefore, we propose an antenna to improve the gain by loading a metal grid on the step reflector surface, as compared to the conventional antenna design. Prototype verification shows the effectiveness of the antenna.