Design of a Broadband Dual Circularly Polarized Septum Antenna

In this paper, a wideband dual circular polarization septum antenna working in X-band is presented. The antenna can realize dual circular polarization by inserting a stepped metal septum in the rectangular waveguide. The bandwidth of the antenna is widened by loading the dielectric in the rectangular waveguide and using a stepped feeding at the bottom of the antenna, which makes the antenna element convenient for array application. The simulation results show that the proposed antenna can obtain a 15% bandwidth for the VSWR less than 2, the isolation between the input ports less than -10 dB, and the axial ratio less than 3 dB.