Millimeter-wave single feed dual-polarized air-filled SIW slotted antenna array

In this work, a single fed dual-polarized air-filled substrate integrated waveguide (ASIW) slotted array antenna for operation in millimeter-wave frequencies is presented. A waveguide slot configuration that can radiate nearly equal components of horizontal and vertical polarizations is presented which is used to design a dual-polarized antenna with a single feed. An arrangement of slots is designed based on the optimization of aperture fields from a combined configuration of transverse and longitudinal slots to obtain dual-polarized radiation. The antenna comprises 8 elements of the designed slot pattern terminated with a short circuit. The spacing between the consecutive array elements and the placement of short circuit is optimized to achieve the dual-polarized radiation over good bandwidth. The antenna features input reflection better than $-10 \mathrm{~dB}$ for a bandwidth of 1.2GHz from 37.3-38.5 GHz with an efficiency over 75% in the entire bandwidth. The maximum gain realized in horizontal and vertical polarizations at 38.2GHz is 9.7dBi and 10.1dBi, respectively. The proposed antenna is fabricated and the measured results are in good agreement with the simulated ones.