Novel circularly polarized slot array antennas with a wide 3-dB axial ratio bandwidth based on a spindle-shaped radiating cavity
Hai Wang, Xue Lei, Tiandong Duan, Tianpeng Li, Jun Gao, Mingyang Zhao
A novel wide 3-dB axial ratio (AR) circularly polarized 2 × 2 array antenna is proposed in this paper. The spindle-shaped coupling cavity with tilted waveguide is capable of generating circular polarization waves from incident linear waves, which improves the AR bandwidth (ARBW) of the antenna. With this structure, a similar amplitude of the two orthogonal transmitted wave components and a stable