Antenna-filter-antenna-based cell for linear-to-circular polarizer transmit-array

In this paper, we propose a dual-band linear-to-circular polarization converter element based on the antenna-filter-antenna (AFA) structure. The traits of this cell include thin three-layer structure and ability to convert a linear incident wave to two orthogonal circular polarizations at two non-adjacent frequency bands. This combination of physical and electrical specifications makes this cell a novel solution. An example of this cell suitable for satellite communication is designed to operate at 20GHz and 30GHz (satellite Ka-band) with 4% and 8% bandwidth, respectively.