Illusion electromagnetics for free-standing objects using passive lossless metasurfaces

摘要

An electromagnetic illusion technique for free-standing objects for far-field observation using passive lossless metasurfaces is presented. Over a closed surface, the electric and magnetic surface currents needed for generating the scattered fields associated with a given physical scalterer are obtained using the surface equivalence principle. The closed surface defines an impenetrable metasurface characterized by surface impedance. A set of auxiliary evanescent surface waves are introduced and optimized over the entire surface to make the metasurface pointwise passive and lossless. Example 2D designs in TE polarization show that desired scattered fields are established immediately away from the illusion device surface. The illusion metasurfaces may be realized as tensor gradient metasurfaces.