• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.356-360
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• 2002

Leaky modes on a circular dielectric rod are investigated from the precisely determined normalized complex propagation constants using Davidenko's complex root finding technique. Below the cutoff frequency of the guided mode, distinct frequency regions that have unique properties are observed, such as nonphysical region, antenna mode region, reactive mode region, and spectral gap region. The effects of tro design parameters, dielectric constants and the radius of the rod, to the leaky mode characteristics are also considered.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.5
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• pp.199-206
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• 2003

Numerical solutions to complex characteristic equations are quite often required to solve electromagnetic wave problems. In general, two traditional complex root search algorithms, the Newton-Raphson method and the Muller method, are used to produce such solutions. However, when utilizing these two methods, the choice of the initial iteration value is very sensitive, otherwise, the iteration can fail to converge into a solution. Thus, as an alternative approach, where the selection of the initial iteration value is more relaxed and the computation speed is high, Davidenko's method is used to determine accurate complex propagation constants for leaky circular symmetric modes in circular dielectric rod waveguides. Based on a precise determination of the complex propagation constants, the leaky mode characteristics of several lower-order circular symmetric modes are then numerically analyzed. In addition, no modification of the characteristic equation is required for the application of Davidenko's method.