Single-layer broadband vertically polarized endfire magnetoelectric dipole loop antenna and array

Abstract

A single-layer broadband vertically polarized endfire magnetoelectric dipole (ME-dipole) antenna and an antenna array. The main radiator of this antenna is a substrate-integrated closed loop, which consists of two horizontal metallic strips printed on the upper and lower surfaces of substrate and a pair of vertical metallic vias. Excited by a double-sided parallel-strip line at the center of the loop, the metallic vias function as electric dipoles while the entire loop aperture works as magnetic dipole. To facilitate integration, this magnetoelectric dipole loop antenna is fed by an open-ended substrate integrated waveguide (SIW), which also works as a backed cavity to enhance the front-to-back ratio. Moreover, rectangular slots are etched at the edges of the SIW aperture to further improve the front-to-back ratio and also the cross-polarization performance. Thus, a vertically polarized endfire ME-dipole loop antenna with a low-profile structure, broad bandwidth, and stable radiation performance is achieved.