Parametric Doppler effect in the case of oblique incidence in a medium with a plasma dispersion law

The parametric Doppler effect that occurs upon reflection of a plane monochromatic wave obliquely incident on an inhomogeneity of the refractive index moving in a medium with a frequency dispersion (homogeneous wave regimes) is analyzed. For a plasma-type frequency dispersion, the dependences of the frequency and angle of reflection on the frequency of the incident wave and on the angle of incidence are found.