Radiation modes and step discontinuities in dielectric rib waveguide

The continuous spectrum of the rib waveguide is derived by a method that ensures orthonormality and completeness of the spectrum. A relatively simple approximation of this continuum for most cases of common interest is obtained. The theory is applied to the abrupt step discontinuity in the E-plane of the rib guide under LSE polarization and to the abrupt termination problem, including radiative effects never before investigated.<
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