Determination of conductivity profiles by time-domain reflectometry

A new numerical method for the reconstitution of the inhomogeneous media conductivity is described. The conducting medium is nonmagnetic, and its relative permittivity equals one. Its frequency-independent conductivity varies normally to its interface. The medium is normally illuminated by a transverse electromagnetic (TEM) plane wave of causal time dependence. The reconstruction process is a direct approach to the inverse problem. It is based on a space time discretization of an exact integral equation. The conductivity profile is determined step-by-step without approximations other than numerical. Some examples are given to illustrate the most interesting properties of the method; special attention is given to the simulation of experimental errors.