On the Relation between Surface Impedance and Shape of the Perfectly Conducting Objects

A new, simple and fast method for the solution of electromagnetic scattering problems related to perfectly conducting objects of arbitrary shape is presented. The method is based on the representation of the conducting object in terms of a circular one having higher order impedance boundary condition on its surface. Through the Taylor expansion of the total field on the minimum circle covering the object, a universal relation between higher order surface impedances and the shape of the object is obtained. Numerical simulations show that the method yields quite accurate results