Design of Dual-Feed Dual-Polarized Microstrip Antenna with High Isolation and Low Cross Polarization

A broadband dual-feed dual-polarized microstrip antenna with low cross polarization and high isolation is presented. The dual-orthogonal linearly polarized mode is excited by two different feed mechanisms from a single circular radiating patch. One of the two modes is excited by a pair of -shaped probes with a 180° phase differences, and the other is excited by an -shaped aperture. The proposed design has a very simple antenna structure with a wide input impedance bandwidth (23.25% for Port1 and 35% for Port2) and also its two input port isolation is found to be as low as -40 dB. Measured results of the fabricated antenna prototypes are also carried out to verify the simulation analysis.