ANALYSIS OF PROPAGATION ON OPEN MICROSTRIP LINES USING MIXED-ORDER COVARIANT PROJECTION VECTOR FINITE-ELEMENTS

Many different procedures have been proposed for the finite element analysis of dielectric-loaded waveguiding structures. However, most of these approaches are unreliable because of the appearance of spurious modes. Mixed-order covariant projection finite elements have been shown to eliminate difficulties with spurious modes in vector waveguide formulations, The authors have developed a method to analyze open region dielectric-loaded waveguiding problems using mixed-order covariant projection finite elements. Details of the construction of the eigenvalue equation are presented. The treatment of open geometries using local absorbing boundary conditions is discussed, An efficient sparse eigensolver, based on iterative methods, that can solve the resulting nonlinear eigenvalue problem, is described, Analysis results are presented that demonstrate the ability of the formulation to solve for the propagating modes of open microstrip lines without the appearance of spurious modes, (C) 1995 John Wiley & Sons, Inc.