Uniform asymptotic solution for the diffraction by a discontinuity in curvature

An asymptotic solution for the electromagnetic diffraction by a discontinuity in curvature in a perfectly conducting surface or in an impedance surface is developed. The solution is uniform through the reflection transition region. It is of the uat type and gives the field in the transition region up to the order k^-3/2 included where k is the wave number. It is continuous and all its derivatives in the direction normal to the transition direction are continuous. The solution is established for a curvature discontinuity along a generatrix of a two dimensional surface illuminated by a plane wave. Its efficiency is illustrated by numerical examples.