Comparison of the currents in the Dirichlet and Neumann shortwave diffraction problems of a plane wave from smooth prolate bodies of revolution

Abstract

This paper continues the series of works [1–5] on the shortwave diffraction on the prolate body of revolution. The numerical comparison of the wave currents for Dirichlet and Neumann boundary conditions confirms the continuous transition of the current from the lit area into the shadowed zones through Fock’s zone. The formulae for the currents were obtained according to the Leontovich–Fock parabolic equation method [6]. We investigated the influence of the correction term that contains the large parameter, on the Fock’s current. This large parameter reflects body’s elongation. Diffrac- tion formulae obtained in [1,4], give the integral representation of the field in some neighborhood of the point, which is located on the boundary of geometric shadow. These formulae give a continuous transformation from ray field in the lit area to the field in the shadow using Fock’s currents.