An improved finite element analysis for open dielectric waveguides

An improved finite element method for analyzing the open dielectric waveguides is presented. The basic idea of the method is an introduction of a transition region between the interior and exterior regions. The introduction of the transition region, in which the now adaptive interpolation functions are used, makes the total field approximation much more close to the practical field distributions than the simple classical treatment before, and the quality of discretization much better. Dispersion characteristics for several dielectric waveguides are calculated by the improved finite element method. The comparison with the previous results obtained by other methods are made, and much better accuracy has been found. The reliability and efficiency of the improved method are thus verified.