Abstract: Accurate and fast ray tracing in arbitrarily shaped cavities is realized in this article based on non-uniform rational B-splines (NURBS) modeling technique and a secondary development of Unigraphics(UG). A novel ray-tracing method is developed, which overcomes the disadvantages in ray-tracing of the traditional shooting and bouncing ray (SBR) method. Software is developed based on the novel method to calculate the radar cross section (RCS) of an arbitrarily shaped complex cavity and corner structure, in which cavity modeling and its RCS calculating are integrated in UG to provide a universal and promising platform for engineers to conduct easy cavity modeling and RCS simulation with good accuracy and high performance. Finally, the RCS of a circle cylinder, a dihedral comer reflector and an S-shaped inlet is calculated, and the results demonstrate high accuracy of the proposed method.

Key words: inlet, arbitrarily shaped cavity, electromagnetic wave scattering, radar cross section, shooting and bouncing ray, ray tracing, secondary development of UG