Design of A Dual-Circular Polarized Antenna Array for Dual-Band Aperture-Shared Applications

This paper presents a dual circularly polarized dual-band antenna array based on frequency selective surfaces, including a
$2\times 2\ \text{low}$
-band (LB) antenna array with four
$2\times 2$
high-band (HB) antenna arrays underneath. The proposed LB antenna operating at 1.7-2.4 GHz (34.10/0) consists of an Frequency Selective Surface (FSS) based radiator and two feeding coaxial lines. Four HB units distributed under each LB unit. Besides, the passband of the proposed FSS-radiator is designed to cover the operating band of 5–6 GHz (18.2%). As a result, the radiation of the HB units can transmit through the FSS-radiator of the LB units. For demonstration, a prototype is designed and fabricated. The suggested design has been produced and tested, and the measured results match the simulations well.