Asymptotic boundary conditions for finite element analysis of three-dimensional transmission line discontinuities

Author

Khebir, Ahmed ; Kouki, Ammar B. ; Mittra, Raj

Author_Institution

Dept. of Electr. & Comput. Eng., Illinois Univ., Urbana, IL, USA

Volume

38

Issue

10

fYear

1990

fDate

10/1/1990 12:00:00 AM

Firstpage

1427

Lastpage

1432

Abstract

The finite element method is used to analyze open three-dimensional transmission line structures in the quasi-TEM regime. Starting from the general solution of the Laplace equation in spherical coordinates, a set of asymptotic boundary conditions are derived for three-dimensional quasi-static problems for a spherical outer boundary. The second-order boundary condition is generalized to a box-shaped outer boundary and implemented in the finite element method to solve the potential problem of a rectangular microstrip patch. Numerical results show that the asymptotic boundary conditions yield more accurate results than those obtainable with a perfectly conducting shield placed at the same location

Keywords

boundary-value problems; finite element analysis; integral equations; strip lines; waveguide theory; 3D quasistatic problems; FEA; FEM; Laplace equation; asymptotic boundary conditions; box-shaped outer boundary; finite element analysis; potential problem; quasiTEM regime; rectangular microstrip patch; spherical coordinates; spherical outer boundary; surface integrals; transmission line discontinuities; Boundary conditions; Capacitance; Conductors; Distributed parameter circuits; Finite element methods; Geometry; Laplace equations; Microstrip; Transmission line discontinuities; Transmission lines;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.58681

Filename

58681