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Inhomogeneities in refractive index have been suggested as a means of guiding waves in the submillimeter through optical wavelength range. In this paper, asymptotic techniques are applied to the scalar wave equation to determine propagation constants and mode patterns in radially inhomogeneous transmission systems with circular cross sections. Results are obtained with the variation of refractive index specified only as a general class of functions. Rectangular geometries are treated as a special case.
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Streifer et al. (1967) studied this question.
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