Calculation of reflection coefficient of complicated inhomogeneous layers using piecewise constant and piecewise linear approximation

The methods of piecewise constant and piecewise linear approximation of complicated inhomogeneous layers are investigated. The expressions for transmission matrices for linearly inhomogeneous and exponentially inhomogeneous layers have been obtained. The accurate and approximate values of reflection coefficient against frequency for the exponential and linear matching layers have been obtained. Piecewise constant and piecewise linear approximation methods have been compared according the criteria of calculation time consuming and accuracy of the result.