Design of a Novel Dual-band Dual-circularly Polarized Waveguide Slot Array Antenna

Abstract

A novel dual-band dual-circularly polarized waveguide slot array antenna is designed. The antenna opens two orthogonal slots with different lengths on the standard waveguide and is excited at two frequencies. The electric fields of TE10 and TE01 modes are obtained. To achieve the purpose of dual-band dual-circular polarization. Two orthogonal slots can not only make the antenna elements have slow-wave properties and delay phase, but also make the antenna elements in different frequency bands have the same virtual short-circuit wall, which simplifies the difficulty of design and processing. The antenna can achieve an equidistant array and become an array antenna. Through simulation verification, the S11<-10 dB in the two frequency bands from 11 GHz to 11.3 GHz and from 13.1 GHz to 13.8 GHz. In this bandwidth, the axial ratio bandwidth is less than 3 dB, respectively. The isolation between the two ends is better than 12 dB, and it has left and right circular polarization. The problem of the deterioration of the axial ratio of the circular polarization of the antenna caused by the different phases between the waveguide slot antennas is solved.