Method of Anisotropic Metasurface Unit Cell Surface Impedance Calculation

High gain antennas based on metasurfaces with modulated surface impedance are a new class of antennas that have appeared in the last decade. They characterized by a simple design, but a relatively complex synthesis procedure. The paper briefly describes the modulated metasurface antennas principle of operation, and gives a specific method for calculating the anisotropic cell impedance tensor based on the calculation of cell eigenmodes in the infinite surface approximation. The method is intended for use at the first stage of the metasurface antenna synthesis, which consists in creating a database of cell tensorial impedances.