Single-fed circularly polarized patch antenna for 60 GHz wireless applications

Millimeter wave technology has facilitated new commercial gigabit wireless applications which require large bandwidth. Circular polarized millimeter wave antennas act as an efficient tool for suppressing the multipath fading effects seen in millimeter wave band. In this paper, a circularly polarized substrate integrated waveguide fed aperture coupled antenna at 60 GHz is presented. The circular polarization is achieved using cross slot on the patch. Simulated result shows that at 60 GHz the axial ratio is better than 0.3 dB, which is closer to the ideal axial ratio value for circular polarization. The antenna provides good impedance bandwidth of 10% (59-65 GHz) and reasonably good 6-dB axial ratio bandwidth.