Dual-Band Circularly Polarized Shared-Aperture Antenna Array for Satellite Communications

This paper presents a dual-band, circularly polarized, shared-aperture antenna array for satellite communications. The antenna array operates in two distinct frequency bands: K-band and Ka-band. The K-band radiating element is an open-loop an-tenna integrated into the array, while a circular microstrip radia-tor is positioned at the center of the K-band open-loop antenna to enhance the efficiency of the aperture reuse. Both dual-band radi-ating elements are printed on the substrate surface and are inde-pendently excited via coaxial pins, enabling seamless integration with CMOS chips and circuits in tile-based T IR modules. Due to the compact structure and simple feeding, the low cost and light weight can be achieved. Simulated results demonstrate that the proposed antenna array achieves beam scanning of 40° in the Ka-band and 60° in the K-band.