Dual-Band Circularly-Polarized Beam-Steerable Reflectarray for Satellite Applications in the Ku band

This work presents the design of a dual-band reconfigurable circularly polarized (CP) reflectarray (RA) antenna for satellite communication in the Ku bands. Simultaneous and independent control is provided over the downlink and uplink beams at frequency bands of [10.8 - 11.8] GHz and [13.8 - 15] GHz, respectively. The unit cell is composed of two circular rings, each loaded using four varactor diodes, for operating in the two bands. The rings are symmetrically loaded in the vertical and horizontal directions to provide an isotropic response suitable for CP applications, and enable a phase range of more than 300 degrees as the capacitive loading varies. Here, the response of the unit cell is studied through fullwave simulations and quasi-optical (QO) measurements, and a fabricated prototype of the RA is presented.