Published online by Cambridge University Press: 16 April 2021
A circularly polarized high-power antenna with higher-order mode excitation (TM01) is presented in this paper. The proposed structure consists of metal plates placed on the conical horn antenna's aperture for achieving TM01 to circular polarized TE11 mode conversion at the output. The structure is simulated on CST Microwave Studio. The designed antenna exhibits high gain and a directive radiation pattern. The axial ratio of the proposed structure is below 3 dB. The simulated and measured reflection coefficient for TM01 mode excitation is below −10 dB over a frequency range of 2.95–3.13 GHz. The structure is purely metallic, and the calculated high-power microwave (HPM) capability is up to the MW level. The proposed antenna is helpful for portable HPM systems.