Cross-Polarization Suppression of Dual-Polarized Planar Patch Antenna Arrays Using Parasitic Elements

This paper presents a design example of a parasitic element aimed at suppressing cross-polarization levels in a polarization-shared planar patch antenna. The proposed parasitic element enhances the cross-polarization level of the E-plane main polarization in a single antenna element by 17.2 dB and that of the H-plane by 3.8 dB. When used in a 2 × 2 antenna array, the configuration improves the E-plane cross-polarization level by 17.1 dB and that of the H-Plane by 13.4 dB after incorporating the parasitic element.