Developme nt of circularly polarized antennas based on dual-mode hexagonal SIW cavity

In this paper, hexagonal substrate integrated waveguide (S IW) cavity is introduced to realize two low profile, single fed and circularly polarized (CP) cavity antennas for the first time. One of the structures presents right handed CP (RHCP), while the other one offers left handed CP (LHCP). The two proposed antennas are compact and are light in weight. They can be easily fabricated using only a single layer of printed circuit board (PCB). Other advantages of these antennas are including low fabrication cost and easy integration with planar circuits. The proposed antennas are successfully designed, fabricated and tested. Measured results are in a very good agreement with those simulated in Ansoft HFSS. The obtained results show that the proposed antennas have also the advantages of conventional cavity backed antennas including high gain and high front to back ratio.