Dual-band Dual-Circular Polarization Miniature Co-Aperture Microstrip Antenna

This paper proposes a high isolation, miniaturized Ku/Ka dual-band dual -circular polarization co-aperture antenna. The Ku unit works at 16Ghz and uses the single-feed method to achieve left-hand circular polarization, then the Ka unit works at 27Ghz which utilizes the double-feed method to achieve right-hand circular polarization. With the help a stacked layout, a square metal patch is inserted between them, which increases the isolation of two radiation ports, and also served as the GND of the upper patch. The simulation results show that the antenna achieves 6.25% axial ratio bandwidth in ku band and 3.8% in ka band, more than 20dB isolation between two feeding ports. The gain of the ku band is 6dBi and ka band is 4dBi.