Bragg reflection in waveguiding structure with nonperiodic radial and angular perturbation of permittivity

In the present work oblique incidence of cylindrical waves on the waveguiding structure with two-dimensional (radial and angular) Bragg inhomogeneity of permittivity is considered. The permittivity of dielectric assumes to be presented in the form of a sum of spatial nonperiodically oscillating harmonics of perturbation. Amplitude and wavenumber of each harmonic smoothly Vary along radial coordinate. The perturbation as a function of the angular coordinate. is expressed in the form of a Fourier expansion.