Compact Integrated Circular Polarization Filtering Antenna based on SIW Cavity

In this paper, a compact integrated circular polarization filtering antenna is proposed based on substrate integrated waveguide (SIW) cavity. Firstly, a dual-mode (TE102 and TE201 modes) rectangular cavity is utilized as a common feeding cavity to achieve a dual-mode filtering response. And then, an additional rectangular patch with a slot is coupled from the feeding cavity for circular polarization radiation. To verify the proposed concept, a prototype circular polarization filtering antenna is simulated. The circular polarized filtering antenna resonates at 4.225 GHz with a low cross-polarization and a high gain of 7.23 dBi.