A Metaspiral Antenna for Azimuthal Beam Steering

A metaspiral antenna is investigated for the capability of steering its circularly polarized beam in the azimuth direction. The feed of this antenna is a combination of a ζ-type feed and an α-type feed that have weighting coefficients Z and A, respectively. The ζ- and α-type feeds generate different phase distributions around the z-axis normal to the antenna plane, creating a radiation beam that i…