Approximate method for calculating step discontinuities in rectangular and ridge-type dielectric waveguides

The effective-permittivity method is used to calculate frequency dependences of E11(y) mode damping due to reflection and radiation at step discontinuities of one of the transverse cross sections in rectangular and ridge-type dielectric waveguides. A qualitative explanation of these dependences is given, and experimental results are presented. The results obtained make it possible to evaluate reflection and radiation losses due to height or width discontinuities of the dielectric slab or directing ridge in rectangular and ridge-type dielectric waveguides.