A Discrete Fourier Transform-Based Framework for Analysis and Synthesis of Cylindrical Omega-bianisotropic Metasurfaces

TL;DR

This paper introduces a Fourier transform-based method for analyzing and designing cylindrical omega-bianisotropic metasurfaces, enabling efficient prediction and synthesis of electromagnetic field transformations without active components.

Contribution

It presents a novel framework combining mode matching and digital signal processing techniques for metasurface analysis and synthesis, addressing key challenges in passive, lossless device design.

Findings

Successfully predicts scattered fields for specified metasurfaces

Designs metasurfaces supporting arbitrary field transformations

Numerical verification confirms robustness and versatility

Abstract

This paper presents a framework for analyzing and designing cylindrical omega-bianisotropic metasurfaces, inspired by mode matching and digital signal processing techniques. Using the discrete Fourier transform, we decompose the the electromagnetic field distributions into orthogonal cylindrical modes and convert the azimuthally varying metasurface constituent parameters into their respective spectra. Then, by invoking appropriate boundary conditions, we set up systems of algebraic equations which can be rearranged to either predict the scattered fields of prespecified metasurfaces, or to synthesize metasurfaces which support arbitrarily stipulated field transformations. The proposed framework facilitates the efficient evaluation of field distributions that satisfy local power conservation, which is one of the key difficulties involved with the design of passive and lossless scalar metasurfaces. It represents a promising solution to circumvent the need for active components, controlled power dissipation, or tensorial surface polarizabilities in many state-of-the art conformal metasurface-based devices. To demonstrate the robustness and the versatility of the proposed technique, we design several devices intended for different applications and numerically verify them using finite element simulations.