SIMULTANEOUS RECONSTRUCTION OF PERMITTIVITY AND CONDUCTIVITY PROFILES IN A RADIALLY INHOMOGENEOUS SLAB.

Abstract

This paper considers the simultaneous reconstruction of permittivity and conductivity profiles in a cylindrically stratified geometry. It is assumed that both the permittivity and conductivity may only vary in the radial direction, and that the unknown region, to be probed, is an annulus of known thickness. An iterative method for the simultaneous inversion of the radial permittivity and conductivity profiles inside this annulus is presented. This method employs a distorted-Born approximation at each iteration step. The inherent nonuniqueness of the problem is circumvented by imposing additional constraints that limit the set of feasible solutions. Numerical simulations show that good results can be obtained for smoothly varying profiles even when a limited number of measurements at a single frequency are used.