Millimeter-wave circularly polarized cavity-backed slot antenna based on SIW

This paper proposed a circularly polarized cavity-backed slot antenna based on substrate integrated waveguide (SIW). The resonant cavity of the antenna is constructed to suppress the electromagnetic waves radiating downward, and the feed SIW is used for slot coupling feeding to reduce the loss, and a pair of rotating triangular patches are introduced into the radiation layer, which are excited by the resonant cavity. For the patch, the surface current flows along the edge of the patch. Since the electric field components of the two right-angle side currents are orthogonal to each other, a circularly polarized wave is formed to radiate energy outward. 18%, and the axial ratio bandwidth reaches 11.1%.