volume | PIER Journals

Abstract

This paper presents a rigorous approach for the propagation of electromagnetic (EM) fields along a helical waveguide with arbitrary profiles in the rectangular cross section. The main objective is to develop a mode model to provide a numerical tool for the calculation of the output fields, output power density, and output power transmission for an arbitrary step's angle and the radius of the cylinder of the helical waveguide. Another objective is to demonstrate the ability of the model to solve practical problems with inhomogeneous dielectric profiles. The method is based on Fourier coefficients of the transverse dielectric profile and those of the input wave profile. Laplace transform is necessary to obtain the comfortable and simple input-output connections of the fields. This model is useful for the analysis of dielectric waveguides in the microwave and the millimeter-wave regimes, for diffused optical waveguides in integrated optics. The output power transmission and the output power density are improved by increasing the step's angle or the radius of the cylinder of the helical waveguide, especially in the cases of space curved waveguides.

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Dr. Zion Menachem

Dr. M. Haridim