RADIO SCIENCE, vol.29, no.6, pp.1403-1407, 1994 (SCI-Expanded)
A correction to the Kirchhoff-Huygens approximation in the format of a diffraction coefficient is derived for an aperture terminated by a half plane. As in the physical theory of diffraction (PTD), this is achieved by considering the end point contribution to the aperture integral. It is seen that when the aperture is taken as conformal with the surface of the half plane, the conventional PTD result is obtained.