Finite element analysis of lossy dielectric waveguides

Lossy dielectric waveguide problems are analyzed by applying an efficient finite-element approach which can deal with waveguides of arbitrary cross-section and transverse inhomogeneity, anisotropy, and significant loss. This method gives solutions directly for the complex propagation constant without spurious solutions and retains its efficiency, which is based on (1) the use of the most economical field representation (in terms of only the transverse components of the magnetic field), achieved without sacrificing the sparsity of the resultant matrices, and (2) the use of a highly efficient solver for large, sparse, nonsymmetric, and complex generalized eigenvalue problems. Examples of lossy waveguide problems are studied, and the results are compared with those obtained by other workers