A novel dual-polarized, wide-band microstrip patch antenna with aperture coupling

A novel dual-polarized aperture-coupled microstrip patch antenna with a wide bandwidth, high isolation, low cross-polarization levels and low backward radiation levels is designed and its features are presented. The square microstrip patch is fed at two comers via the H-shaped apertures. The theoretical analysis is based on the finite-difference time-domain method. A parametric study on the input impedance of the antenna with a single input port is presented and a dual-polarized antenna is then designed, fabricated and measured. The measured return loss exhibits an impedance bandwidth of over 24.4% and the isolation between two polarization ports is better than 30 dB over the bandwidth. The cross-polarization levels in both E and H planes are better than -23 dB. The front-to-back ratio of the antenna radiation pattern is better than 22 dB.