The UTD analysis to EM scattering by arbitrarily convex objects using ray tracing of creeping waves on numerical meshes

The UTD analysis to the diffraction of electromagnetic (EM) waves by smoothly convex surfaces is of great importance in many problems, such as the EM compatibility, the analysis of coupling between two antennas, and the estimation of scattering properties. When a ray illuminates on the curved surface at grazing incidence, the ray-propagating direction is tangent to the curved surface at the incident point, and then surface rays are launched. These surface rays, or creeping waves, propagate along geodesic paths on the convex surface starting from the incident point. Hence the ray tracing of creeping waves on the convex surface is a key process in the UTD method. Usually, some typically geometric objects are used to approximate a certain of objects for engineering applications. However, it is difficult to use such typically geometric objects to approximate arbitrarily-shaped objects, which limits the application of the UTD method.