Design of 3D Conformal Metasurfaces

A general synthesis technique for 3D conformal metasurfaces is presented which utilizes integral equation-based modeling techniques and rapid optimization methods. The metasurfaces considered consist of conformal impedance sheets above conformal ground planes. The metasurfaces are modeled using integral equations and RWG basis functions which accu-rately account for all mutual coupling and finite dimensions. A conformal metasurface is designed in two phases: a Direct Solve phase involving the solution of the governing integral equation via the method of moments to obtain an initial design with complex-valued impedance sheets satisfying the desired far-field beam specifications, and a subsequent Optimization phase to convert the complex-valued sheets into purely reactive sheets. To accelerate this step, the metasurface is optimized using an adjoint optimization method. A metasurface with sinusoidal curvature is designed using this approach.