A Wideband Circularly Polarized Crossed-Slot Antenna with Stable Phase Center

Abstract

A wideband circularly polarized crossed-slot antenna with a stable phase center is investigated in this letter. The proposed antenna consists of a crossed-slot radiator and a Γ-shaped feeding structure. Orthogonal modes can be excited by perturbing the crossed slot to realize circular polarization. Both simulation and measurement of the designed antenna demonstrate a-10 dB impedance bandwidth of 43.8% and a 3 dB axial-ratio bandwidth of 42.6%, covering all the global navigation satellite system (GNSS) bands. Due to the overall symmetry of the radiation crossed slot, a phase center of the proposed antenna remains stable within a wide beam of 100° covering the whole GNSS bands, with phase center variation retained below 5°.