Finite-difference time-domain implementation of surface impedance boundary conditions

Author

Beggs, John H. ; Luebbers, Raymond J. ; Yee, Kane S. ; Kunz, Karl S.

Author_Institution

Dept of Electr. & Comput. Eng., Pennsylvania State Univ., University Park, PA, USA

Volume

40

Issue

1

fYear

1992

fDate

1/1/1992 12:00:00 AM

Firstpage

49

Lastpage

56

Abstract

Surface impedance boundary conditions can be utilized to avoid using small cells, made necessary by shorter wavelengths in conducting media throughout the solution volume. The standard approach is to approximate the surface impedance over a very small bandwidth by its value at the center frequency, and then use that result in the boundary condition. In this paper, two implementations of the surface impedance boundary condition are presented. One implementation is a constant surface impedance boundary condition and the other is a dispersive surface impedance boundary condition that is applicable over a very large frequency bandwidth and over a large range of conductivities. Frequency domain results are presented in one dimension for two conductivity values and are compared with exact results. Scattering width results from an infinite square cylinder are presented as a two dimensional demonstration

Keywords

boundary-value problems; difference equations; electromagnetic wave scattering; time-domain analysis; FDTD method; conducting media; electromagnetic scattering; finite difference time-domain method; infinite square cylinder; surface impedance boundary conditions; Bandwidth; Boundary conditions; Conductivity; Dispersion; Finite difference methods; Frequency domain analysis; Scattering; Surface impedance; Surface waves; Time domain analysis;

fLanguage

English

Journal_Title

Antennas and Propagation, IEEE Transactions on

Publisher

ieee

ISSN

0018-926X

Type

jour

DOI

10.1109/8.123352

Filename

123352