A Dual-Wideband Dual-Polarized Aperture-Shared Patch Antenna With High Isolation

A dual-wideband dual-polarized aperture-shared patch antenna with high isolation is proposed, which consists of an S-band circularly polarized antenna and an X-band linearly polarized antenna. The S-band antenna adopts the stacked patches, where the upper parasitic patch is introduced for increasing gain and bandwidth and also works as a ground plane for the X-band excited patch. The X-band feed coaxial line perforates the center of S-band excited patch and parasitic patch, so that the coshared aperture antennas are tightly integrated and have a high isolation. The simulated and measured results are matched well and show that the proposed antenna obtains 10 dB impedance bandwidths of 19.3% and 22%, peak gains of 10.8 dBi and 8.5 dBic, for X-band and S-band, respectively. Meanwhile, the 3 dB axial-ratio bandwidth of the S-band is 19.2% and the port isolation between S- and X-bands is higher than 32 dB.