A high isolation dual-polarized microstrip patch antenna based on backed substrate integrated cavity and pins-loaded cross slot

摘要

A X-band aperture-coupled patch antenna based on backed substrate integrated cavity (SIC) and pins-loaded cross slot with dual linear polarization and high isolation is investigated. Loaded pins are applied to cross aperture to reduce the mutual coupling between the slots. SIC is used to reduce the coupling caused by parallel plate mode. Moreover, one-cross-point structure of feed networks is used to further improve the isolation. A prototype of the dual-polarized antenna is fabricated and measured. The measured results show that the dual-polarized antenna exhibits impedance bandwidths better than 30% (voltage standing wave ratio <= 2), cross polarizations better than -27 dB. And the isolation between the two ports is above 51 dB. To the best knowledge of the authors, this is the highest isolation yet achieved for a patch antenna with wide bandwidth.