An asymptotic estimate of the edge effects in the high frequency Kirchhoff diffraction theory for 3-d problems

► We analytically estimate the edge effects in 3-dim high-frequency diffraction problems. ► Our approach is based on the classical Kirchhoff integral representation. ► The diffracted field is deduced as the sum of the leading term expressing the mirror Ray theory reflection, plus the contribution from the obstacle's boundary contour. ► This contribution is given through a line integral over the contour, and has been evaluated analytically for some concrete geometric cases. ► The agreement with full numerical calculations is excellent.