The Target CAD Modeling And RCS Calculation Based On Pixel Method

The application of pixel method on the object CAD modeling and target RCS calculation are mainly discussed in this thesis. Z-Buffer algorithm is used to model the hidden configuration of the target which displayed with pixels, and the PO method is presented to calculate the RCS of both single and double stations. In this method, the shape of the object is divided into many quadrangles. Plus the scattered field of each quadrangles, we can get the total scattered field and the target RCS. Then the rapid analysis of radar target characteristic is made.The formula for the scattered field of quadrangles is deduced from the Kirchhoff-Helmholtz repression. The Kirchhoff-Helmholtz representation which is for the far field scattered by a flat metallic plate of arbitrary shape is a double integral. In the far field approximation, this double integral can be reduced to a sum calculation of each pixel which is projective on the computer screen. The deducing is given in this paper and the additive form expression is applied to RCS prediction of double stations.For accurate analysis of the target characteristic of curved surface targets, a algorithm of curved surface pixel is developed in the thesis. The configuration data of grid are fitted to surface by use of Coons curved surface and spline interpolation, and a method of pixel hidden and target characteristic analysis is designed for parameter surface.The calculating code is designed with MS Visual C++6.0 development tools, and the soft's graphical functions are from OpenGL graphical library. A visual program system which has perfectly complete functions is built. The results indicate that the speed of this system is fast and the precision achieves the range of 3～5 dBsm.