A Wideband Circularly Polarized Antenna Based on the Patch Resonator and SIW Cavity

A circularly polarized (CP) antenna with wide bandwidth is presented based on the circular patch resonator and square substrate integrated waveguide (SIW) cavity in this paper. By embedding the circular patch resonator in the middle of the square SIW cavity, multiple resonances are created. Then, a slot is etched in the patch resonator to realize right-handed circular polarization (RHCP). Simulation outcomes demonstrate that the proposed antenna has achieved the -10dB impedance bandwidth of 2.88-3.11GHz. Besides, two axial ratio (AR) nulls are produced so as to result in an enhanced 3dB AR bandwidth of 2.97-3.09GHz.