Title :
A simplified formulation to analyze inhomogeneous waveguides with lossy chiral media using the finite-element method
Author :
Valor, Luis ; Zapata, Juan
Author_Institution :
Dept. de Electron. y Teoria de Circuitos, Univ. Europea de Madrid, Spain
fDate :
2/1/1998 12:00:00 AM
Abstract :
In this paper, an efficient finite-clement formulation is presented for the analysis of the propagation characteristics in arbitrarily shaped lossy inhomogeneous waveguides loaded with chiral media. It is a simplified form of the one proposed for the bi-anisotropic media. In this formulation, showing no spurious modes, the frequency or the propagation constants may be treated as eigenvalues of a resulting sparse quadratic eigenproblem. However, in order to handle losses easily and to facilitate computation of complex modes, the frequency is specified as an input parameter and the eigensystem is solved for the complex propagation constant as the eigenvalue. This sparse eigensystem is further transformed into a generalized one, thus maintaining the sparse properties of the matrices. New numerical finite-element results are presented
Keywords :
chirowaveguides; eigenvalues and eigenfunctions; finite element analysis; sparse matrices; waveguide theory; complex modes; complex propagation constant; eigenvalues; finite-element method; inhomogeneous waveguides; input parameter; lossy chiral media; propagation characteristics; sparse quadratic eigenproblem; Admittance; Eigenvalues and eigenfunctions; Electromagnetic waveguides; Finite element methods; Frequency; Magnetic fields; Nonhomogeneous media; Optical waveguides; Propagation constant; Propagation losses;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on