Absorbing boundary conditions for the finite-element analysis of planar devices

Author

Webb, J.P.

Author_Institution

Dept. of Electr. Eng., McGill Univ., Montreal, Que., Canada

Volume

38

Issue

9

fYear

1990

fDate

9/1/1990 12:00:00 AM

Firstpage

1328

Lastpage

1332

Abstract

The finite-element method is used to determine the scattering matrices of open devices in two dimensions. Microwave and optical devices in which the fields are not confined to a finite region can be analyzed with the finite-element method if special boundary conditions are used to absorb outgoing radiation. The absorbing boundary conditions can be imposed by the addition of two terms to the usual functional for the scalar Helmholtz equation. Universal matrices are introduced to allow the additional terms to be easily assembled, for polynomial orders one through four. Results are given for the impedance of a parallel-plate waveguide radiating into free space and for the scattering parameters of three dielectric slab waveguide devices: a rectangular discontinuity, a feed structure, and a junction

Keywords

S-matrix theory; dielectric waveguides; finite element analysis; waveguide components; waveguide theory; absorb outgoing radiation; absorbing boundary conditions; dielectric slab waveguide devices; feed structure; finite-element analysis; finite-element method; junction; microwave devices; optical devices; parallel-plate waveguide radiating into free space; planar devices; rectangular discontinuity; scalar Helmholtz equation; scattering matrices of open devices; scattering parameters; Boundary conditions; Finite element methods; Microwave devices; Microwave theory and techniques; Optical scattering; Optical waveguides; Rectangular waveguides; Transmission line matrix methods; Waveguide discontinuities; Waveguide junctions;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.58660

Filename

58660