Two-dimensional diffraction by impedance loaded structures with corners

A numerical study of the scattering of an E-polarised plane wave by an infinite cylindrical structure, on which an impedance boundary condition is enforced, is described. The formulation allows structures with corners. It employs an integral equation formulation for which a rapidly convergent quadrature scheme is developed. The computed scattered near- and far-field patterns for some test objects are compared with those of the same objects with rounded corners, where the radius of curvature of the rounding is small.