Dual-Band Dual-Linearly/Circularly polarized Shared-Aperture antenna for satellite communication systems

This paper presents a dual-band dual-linear/circular-polarization shared-aperture antenna for satellite communication. The antenna has dual linear polarization (DLP) radiation performance in K-band and dual circular polarization (DCP) radiation performance in Ka-band. The four radiation patches cut by two slots in the linear polarization structure form a 2 × 2 circular polarization array. By cleverly combining DLP and DCP radiation elements in the substrate integrated waveguide (SIW), low profile and compact size structure are achieved. The proposed DLP and DCP shared-aperture antenna is fabricated by adopting a multilayer PCB technology. Measured results imply the operating bandwidths of 21.6–22.6 GHz and 20.7–22.6 GHz for horizontal polarization (HP) and vertical polarization (VP). Moreover, wide 3-dB axial ratio (AR) bandwidths of the DCP element are achieved, with the peak gain of 6.5 dBi and 7.4 dBi. The antenna with features of low frequency ratio shared-aperture, high polarization diversity and low cost is suited for the millimeter-wave satellite communication system.