Bragg transformation in horns with two-dimensional perturbation of permittivity

The paper considers Bragg reflection and mode conversion of waves of both polarizations in horns filled with a medium having a nonperiodic two-dimensional perturbation of permittivity. The combination of longitudinal and angular quasi-periodic inhomogeneity supplies resonance coupling of waves with different angular numbers or/and directions of propagation. Solution of the boundary-value problem is found by the asymptotic method of Krylov, Bogoliubov and Mitropolsky. The phenomenon of "Brewsterization" of Bragg reflection is investigated.