24-GHz Circularly Polarized Substrate Integrated Waveguide-Fed Patch Antenna

摘要

This paper has presented the design of a 24-GHz patch antenna with characteristics of good circular polarization, simple structure and easy fabrication. The printed antenna consists of two layers of substrates with the lower one for achieving a short-ended substrate integrated waveguide (SIW) and the upper one for supporting the rectangular radiating patch. The left-handed circularly polarized wave has been obtained by etching a 45° rotated cross-shaped slot on the broad wall of the SIW. The obtained results can confirm that the proposed antenna has achieved an impedance bandwidth ($ert mathrm {S}_{11} {ert } le $-10 dB) of 23.1-25.3GHz and the 3-dB axial ratio bandwidth of 23.2-24.7GHz.