A hybrid MM/GTD numerical technique for far-field scattering from impedance boundaries

Burnside et al. [1975] introduced a hybrid numerical technique that combines the moment method (MM) with the geometrical theory of diffraction (GTD) to find the currents on the surface of perfectly conducting scatterers. The hybrid technique extends the traditional MM by describing the current over very large areas using single basis functions derived from GTD, resulting in fewer basis functions and much greater computational efficiency. Here we extend the basic approach of Burnside et al. to allow the application to impedance boundaries as well as perfectly conducting scatterers. The extended technique is then used to find the far-field scattering from infinitely long, lossy rough dielectric scatterers.