3D Method-of-Moment Design of Huygens' Metasurfaces

Electromagnetic metasurfaces (MTSs) are often assumed to be passive and lossless, and can be modeled as purely reactive homogenized impedance sheets on dielectric substrates. In this paper, a 3-D design procedure for reflective metasurfaces based on the integral equation method and impedance boundary conditions is presented. The metasurface consists of impedance sheets placed on top of a grounded dielectric slab, and the impedance values are optimized to match certain far-field (FF) power patterns or to beamform using the gradient-descent method.