Higher-Order Modes in Circular Eccentric Waveguides

Abstract This article presents a method to evaluate the cutoff wave-numbers of higher-order modes of eccentric circular waveguides employing the method of conformal transformation combined with the method of finite difference. Bilinear conformal transformation has been used to transform eccentric cylinders into concentric cylinders. The cutoff frequencies are evaluated from the eigenvalues by solving the characteristic equation expressed in terms of matrices obtained from a set of simultaneous equations satisfying the boundary conditions. A comparison of numerical data with that available in the literature is presented.