Wideband High-Gain Circularly Polarized Resonant Cavity Antenna With a Thin Complementary Partially Reflective Surface

In this communication, a new wideband resonant cavity antenna (RCA) with circular polarization is proposed. A wideband circularly polarized (CP) crossed-dipole antenna acts as the main radiating element inside the cavity. The dipole is designed based on self-complementary structures and utilizes several parasitic patches and posts to obtain wideband circular polarization and impedance characteristics. The incorporation of the proposed antenna with a new broadband thin single-layer dual-sided partially reflective surface (PRS) designed based on the complementary structure contributes to the improvement of the antenna gain in a broad bandwidth. The fabrication of the PRS on both sides of a thin single laminate substrate reduces thickness of the PRS compared with conventional multilayer PRS structures, in which the layers are separated by a gap distance. The measured results, which are in agreement with the simulations, show that the proposed antenna has a maximum measured gain of 12.5 dBic, while the 3 dB gain bandwidth and 3 dB axial ratio bandwidths are 39% and 43.37%, respectively. The measured results demonstrate the wideband functionality of the proposed antenna.