Wedge diffracted waves excited by a line source: exact and asymptotic forms of fringe waves

Abstract

Today's understanding and modeling of diffraction at antennas and scattering objects necessitates further analysis of diffracted fields in the vicinity of scattering edges/tips. This paper derives exact and asymptotic forms of fringe waves excited by a line source around a perfectly reflecting wedge. According to the physical theory of diffraction (PTD), these waves are found as the difference between the exact and physical optics (PO) solutions of the wedge diffraction problem. The exact solution has been well-known for a long time, e.g., H. M. Macdonald, Electric Waves, Cambridge Univ. Press, 1902, pp. 186-198; Electromagnetic and Acoustic Scattering by Simple Shapes, J. J. Bowman, T. B. A. Senior, and P. L. E. Uslenghi, Eds., Hemisphere, 1987. In this paper, we focus on the PO solution. Its new exact and asymptotic forms are derived and the fringe waves are analyzed. Numeric results illustrate the theory.