Abstract
This paper describes several techniques for enhancing the computational efficiency of Metasurface (MS) modeling when the geometry of the MS is either a truncated periodic structure or it is quasi-periodic, with its elements varying slowly along the surface. The quasi-periodic MS is used to introduce a phase (and amplitude) taper in the transmitted, reflected, or propagating wave interacting with the MS. The three key approaches proposed in this paper are based on using: (a) macro-basis functions for matrix-size reduction; (b) effective medium to replace the MS element; GPU to speed up the generation of multilayer Green's function and associated MoM matrix computation.