APPLICATION OF PHYSICAL OPTICS TO THE RCS COMPUTATION OF BODIES MODELED WITH NURBS SURFACES

This paper presents a method for the computation of the monostatic rad ar cross section (RCS) of electrically large conducting objects modele d by nonuniform rational B-spline (NURBS) surfaces using physical opti c (PO) technique. The NURBS surfaces are expanded in terms of rational Bezier patches by applying the Cox-De Boor transform algorithm. This transformation is justified because Bezier patches are numerically mor e stable than NURBS surfaces. The PO integral is evaluated over the pa rametric space of the Bezier surfaces using asymptotic integration. Th e scattering field contribution of each Bezier patch is expressed in t erms of its geometric parameters. Excellent agreement with PO predicti ons is obtained. The method is quite efficient because it makes use of a small number of patches to model complex bodies, so it requires ver y little memory and computing time.