Calculation of reflectometric characteristics taking into account profile inhomogeneity of the transition layer

The influence of a transition layer with a small phase thickness on the results of reflectometric investigations is considered. The expressions for the reflection coefficients of electromagnetic waves with the $p$-wave and $s$-wave polarization are obtained using the perturbation theory. Logarithmic derivative of the reflection coefficient with respect to angle for a wave with the $p$-wave polarization is analyzed. It is shown that near the Brewster angle, the derivative has singularities associated with the electrodynamic parameters of the transition layer. The results of calculations for the diffusion layers are presented.