SHAPE RECONSTRUCTION OF AN IMPENETRABLE SCATTERING BODY VIA THE RAYLEIGH HYPOTHESIS

This work deals with the determination of the shape of a generally non -circular impenetrable cylinder from the way it scatters incident soun d. A complete family (of generally non-orthogonal functions) represent ation of the scattered field is employed to match the total measured f ield. The data equation and state equation, derived from the Rayleigh hypothesis, are grouped into a single nonlinear cost functional which is minimized by means of the modified Levenberg-Marquardt algorithm to obtain the parametric equation of the boundary of the body in the cro ss section plane. Numerical examples of the results of the inversion s cheme are given for cylinders with both convex and non-convex boundari es illuminated by a plane wave with frequency or angle-of-incidence di versity. Potential applications include robotics (artificial vision), non-destructive evaluation and medical imagery.