Extension of PTD for Finite Objects With Rounded Edges: Diffraction at a Soft Trilateral Cylinder

Abstract

The letter extends the physical theory of diffraction (PTD) for objects with rounded edges. It represents a combination of the fundamental PTD concept of fringe currents and the method of moments (MoM). The objects in the vicinity of edges are considered as parts of appropriate tangential wedges. Integral equations are formulated for fringe currents on these wedges and solved by the MoM. Then, a far field radiated by these currents is calculated. A very good agreement is observed with the field produced by the currents induced on the actual scattering object when its size exceeds a few wavelengths.