The Conductivity and Dielectric Constant of a Sphere Determined by Scattered Field Measurements

Modeling the human skull as a homogeneous sphere, a method is presented whereby the unknown conductivity and dielectric constant associated with the sphere can be determined through measurements of the Stokes polarization parameters of the angularly scattered radiation, when the sphere is irradiated by an electromagnetic plane wave. The wavelength of the incident field is on the order of the diameter of the sphere so that the Mie description of the scattered field is employed. The technique requires the minimization of the square of the differences between the measurement and its theoretically computed counterpart. A simple systematic variation in the unknown parameters (complex refractive index) is utilized for the minimization process. Numerical illustrations of the method are presented for computer simulated measurements.