Dual Circularly Polarized Waveguide Array Antenna Formed by Full-Metallic Bow-tie Radiating Cavities

A full-metallic dual circularly polarized antenna based on an array of bow-tie shaped radiating elements is presented in this contribution. The radiating element, formed by a bow-tie shaped cavity, can generate dual circular polarization. It is fed by a square waveguide path that supports the two degenerate modes TE
10
and TE
01
. The excitation of the TE
10
mode in the input port generates left-hand circular polarization while the TE
01
mode generates right-hand circular polarization. Furthermore, a dual circularly polarized array antenna formed by bow-tie radiating elements has been designed. The two degenerate modes TE
10
and TE
01
are supported by a four-way feeding network implemented in square waveguide technology. Both the single radiating element and the dual circularly polarized array have been fabricated by CNC milling techniques. A pure circular polarization performance, high gain or high efficiency have been obtained, experimentally validating the dual circularly polarized bow-tie element in an array configuration.