Scattering from a circular disk: a comparative study of PTD and GTD techniques

Two groups of techniques, PTD (physical theory of diffraction) and GTD (geometric theory of diffraction), are studied by analyzing the scattering from a conducting circular disk. The authors include comparisons of calculations based on several different asymptotic high-frequency theories with the method of moments (MoM) as a baseline. The latter is treated as numerically exact. Features of particular interest include the performance at the reflection boundaries, boresight caustics, and far-angle sidelobes. The bistatic radar cross sections (RCSs) calculated by these techniques are examined. Although only far-field radiation is considered, these methods can also be used for near-field calculations.>