Table of Contents
International Journal of Microwave Science and Technology
Volume 2007, Article ID 85181, 5 pages
Research Article

Numerical Analysis of Inhomogeneous Dielectric Waveguide Using Periodic Fourier Transform

Department of Electrical Engineering, Iran University of Science and Technology Narmak, Tehran 16844, Iran

Received 22 September 2007; Accepted 24 December 2007

Academic Editor: Yue Ping Zhang

Copyright © 2007 M. Moradian and M. Khalaj-Amirhosseini. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


A general method is introduced to obtain the propagation constants of the inhomogeneous dielectric waveguide. The periodic Fourier transform is applied to the normalized Maxwell's equations and makes the field components periodic. Then they are expanded in Fourier series. Finally, the trapezoidal rule is applied to approximate the convolution integral which leads to a set of coupled second-order differential equations that can be solved as an eigenvalue-eigenvector problem. The normalized propagation constant can be obtained as the square roots of the eigenvalues of the coefficient matrices. The proposed method is applied to the dielectric waveguide with a two-layered dielectric profile in the transverse direction, and the first four-confined TE modes are obtained. The propagation constants for the mentioned dielectric waveguide are also derived analytically and are then compared with those derived by the proposed method. Comparison of results shows the efficacy of the proposed method.