Quasi-Optical Excitation of Modulated Metasurface Antennas

We present a new architecture for modulated metasurface (MTS) antennas with rectangular shape and fed by means of a pillbox-type quasi-optical beamformer. Two design examples were numerically simulated, the first one consists of a linearly-polarized antenna with amplitude tapering to increase the aperture efficiency, while the second one provides a circularly-polarized pencil beam. We show that the proposed structure is able to provide high aperture efficiencies similar to those already demonstrated with circular apertures. Moreover, the use of multiple sources in the focal plane allows us to introduce multi-beam capabilities.