Broadband Folded Reflectarray Fed by a Dielectric Resonator Antenna

In this letter, a broadband folded reflectarray (FRA) is designed and fabricated. The FRA consists of a main reflectarray, the polarizing grid, and a feeding dielectric resonator antenna embedded in its structure. With the help of the multilayered reflecting element, the main reflectarray is capable to provide 90°of polarization rotation and proper phase compensation for a linearly polarized incident wave. By altering the microstrip line length, a wide phase coverage can be obtained with a good phase linearity. To validate the FRA design, both simulations and experiments are conducted, and good agreements are obtained. The FRA accomplishes 31% matching bandwidth from 9 to 12.1 GHz. In addition, a high aperture efficiency of 50.3% and the peak gain of 28.08 dBi at 10.8 GHz is achieved. Compared with the published works, the proposed FRA is especially advantageous for low profile and good efficiency.