On the theory of propagation of electromagnetic waves in a waveguide with a multiperiodically modulated dielectric filling

The propagation of TE electromagnetic waves in a waveguide filled with multiperiodically nonuniform dielectric medium is discussed under the assumption of a small modulation index of filling. The frequency of the “strong interaction” between the signal wave and the modulation wave of the filling is found. Clear physical explanations of the effect of strong interactions is given