A regularized Newton method for one-dimensional profile inversion of a lossy cylinder

A regularized Newton iterative method is presented for the determination of one-dimensional profile of an inhomogeneous circularly cylindrical region. The region is assumed to be filled with a lossy dielectric material of which electromagnetic parameters have an arbitrary variation in the radial direction. By using the finite Fourier transformation of field expressions, the problem is first reduced to a system of non-linear operator equations which can be solved through regularized Newton method. The method requires to solve the scattered field and the Fréchet derivatives in the inhomogeneous region in each iteration step. Numerical simulations are carried out to test the applicability and the effectiveness of the method.