Uniform Theory of Diffraction (UTD)
The uniform theory of diffraction (UTD) is an asymptotic highfrequency numerical solver. The method is typically used for electrically extremely large PEC structures.
The Solver has two UTD
solution methods:

 Faceted uniform theory of diffraction (faceted UTD)
 This method is wellsuited for antenna placement on electrically large platforms with curved surfaces (such as aircrafts). It is a frequency independent solver which uses planar mesh triangles to approximate the structures, including surface curvature. The method takes into account multiple reflections, edge and wedge diffraction, corner diffraction and creeping waves.

 Uniform theory of diffraction (UTD) with polygons or cylinder
 This method is wellsuited for antenna placement of electrically large platforms on flat surfaces. It is a frequency independent solver which uses polygons to approximate the structures, but it does not consider surface curvature. This method can also be used to solve a single canonical circular cylinder.