Modeling and Analysis of Printed-Circuit Tensor Impedance Surfaces

• Published in: IEEE transactions on antennas and propagation Vol. 61; no. 1; pp. 211 - 220
• Main Authors: Patel, A. M., Grbic, A.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.01.2013; Institute of Electrical and Electronics Engineers
• Subjects: Anisotropic structures; Applied classical electromagnetism; artificial materials; Dispersion; Electromagnetic wave propagation, radiowave propagation; Electromagnetism; electron and ion optics; Equations; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Impedance; impedance sheets; Mathematical model; periodic structures; Physics; Surface impedance; Surface waves; Tensile stress; tensor surfaces; Surface impedance; Electromagnetism; Printed circuits; Dispersion relations; Eigenmode; Boundary conditions; Wave interaction; impedance sheets; tensor surfaces; TM mode; artificial materials; TE mode; Anisotropic structures; Anisotropic structure; Dielectric substrate; Surface waves; Simulation; Modelling; Tensor method; Normal incidence; Periodic structures
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2012.2220092

Analysis of a printed-circuit tensor impedance surface (PCTIS) is presented. The surface consists of a periodic, subwavelength-patterned metallic cladding printed over a grounded dielectric substrate. First, the dispersion equation for an idealized tensor impedance boundary condition is derived by expressing the field in terms of TE and TM waves. A similar method is then used to find the dispersion equation of the PCTIS consisting of a tensor sheet impedance, which models the metallic cladding, over a grounded dielectric substrate. In addition, a method for extracting the tensor sheet impedance of a periodic, metallic cladding printed over a grounded dielectric substrate, is reported. It involves performing two normal-incidence scattering simulations using a full-wave electromagnetic solver. The method is strictly valid when the ground plane is sufficiently far from the metallic cladding to avoid evanescent-wave interactions. By combining the tensor sheet extraction method with the dispersion equation, the full dispersion characteristics of the PCTIS are analytically predicted in the homogenous limit. The results are verified through full-wave eigenmode simulations.