Study Of Physical Optics Based On NURBS Surface Model And Stationary Phase Method

Based on the non-uniform rational B-spline (NURBS) and Physical Optics (PO) techniques, the radar cross section (RCS) of conducting plate is calculated.1.The mathematical property of NURBS surface and Bezier surface are thoroughly studied, and the specific algorithm of transforming the NURBS surface into the Bezier surface is analyzed. The basic theory of stationary phase method (SPM) is studied and the corresponding formulas are deduced.2.For the modeling of a target by the NURBS technique, at first, the control knots are computed. Then, the weights and knots of different types on the surface are evaluated. Finally, arbitrary points on the NURBS surface,such as a cylinder or a cone, are obtained.3.For the computation of the RCS, firstly, the physical optics integral on the surface of the scatter is transformed into a dual integral of NURBS parameters domain. Then, the integral is changed into summation by the definition of integration and the parameters information of arbitrary points on the NURBS surface. Finally, the RCS is predicted.