Design of a Potter Horn Antenna

Within this paper, a square waveguide Potter horn antenna is designed to excite the higher order modes in the form of a step. The antenna consists of a third-order step and a horn. The higher order modes generated by the step suppress the side lobe in the E-plane, and then the phase between the TE and TM modes is controlled by the length of the horn to realize the rotationally symmetric radiation patterns at apertures. The simulation results show that the antenna has excellent symmetry in the E-plane and H-plane of the radiation patterns in the range of 22-29 GHz with an impedance bandwidth of 27.5%. Its side lobe level is less than -20 dB and the peak gain in band is 17.4 dBi.