ABSTRACT

The inverse scattering problem in electromagnetic fields is studied through the identification or reconstruction of the obstacle. With respect to the measurement Em of the scattered electric field in a non-far zone θ, we consider the classical minimization of a functional measuring the distance between Em and the actual solution E over θ. We derive the expression for the shape derivative of the functional. The shape derivative techniques are those introduced in [1], [6], and [14]. The Maxwell solutions are developed in [3], [5], and [14]. Then we present the shape gradient calculus for a nonsmooth scattering surface, which could be a cylinder. We present numerical results of the shape gradient calculus on a metallic antenna’s surface, using SR3D software. These results are given in a 3D general setting instead of TM or TE.