A Frequency Reconfigurable Fabry-Perot Cavity Antenna

This paper presents a frequency reconfigurable Fabry-Perot Cavity antenna which can continuously change its operating frequency from 5.1 GHz to 6.0 GHz. It consists of a rectangular patch antenna with a parasitic square patch structure acting as the cavity exciter, a superstrate with 9×9 square-patch-type unit cells, and a high impedance surface with 48 phase-varying elements. Each phase-varying element is composed of a bowtie patch printed on the top layer of a substrate and a varactor diode is inserted in the middle of the patch. By tuning the varactor diode on each element, its operating frequency can be varied. Moreover, the antenna's maximum directivity can be shifted with the frequency.