Circularly Polarized Ridge Gap Waveguide Fed SIW Dielectric Resonator Antenna

A circularly polarized planar DRA based on the substrate integrated waveguide (SIW) technology for 60 GHz is introduced. The antenna consists of multilayered structure with perforated dielectric substrate to make dog-bone shaped DRA. The ridge-gap waveguide technology is used to feed the DRA for the surface wave suppression and gain enhancement. The unit-cell of the ridge gap structure has stop-band of 46–95 GHz. The SIW DRA introduces impedance bandwidth from 59.4 GHz to 60.4 GHz with peak gain of 6.78 dBi. The rotation of the dog-bone shaped DRA by 45 degrees produces left-hand CP with a bandwidth of 0.22 GHz. A 2×1 SIW-DRA elements are designed with sequential rotation and phases for CP bandwidth enhancement. The peak gain increases to 7.82 dB, and a broadband axial-ratio (AR) of 4.8 GHz is achieved.