Diffraction from structures with an impedance boundary

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. It employs an integral equation formulation for which a rapidly convergent quadrature scheme is developed. The computed scattered far-field patterns are compared with the results of Rawlins [1] for rectangular structures obtained by high frequency methods, in order to validate his solutions over the range of impedances and wavenumbers examined.