Excitation of surface waves on a unidirectionally conducting screen by an arbitrary phased line source parallel to it

An exact solution is obtained for the scattering problem of a phased line source in front of a screen and parallel to it. The direction of perfect conduction forms an arbitrary angle Ω with the normal projections of the filament on the screen. The coupled surface waves and scattered far field are investigated, and alternative expressions suitable for numerical calculations are presented together with numerical results. It is found that the energy is highly localized in the neighborhood of the screen, and the closer the filament is to the screen, the larger the excitation of the surface wave. In addition, it was found that the surface waves travelling to the right and to the left of the filament are different and become identical only when either Ω=π/2 or the propagation constant γ=π/2. For the special cases γ=Ω and Ω+γ=π, a surface wave is excited in only one side of the screen. In general, the surface waves are slow waves which are circularly polarized with opposite polarization on both sides of the screen. The ordinary end fire source was found to be characterized by 100% launching efficiency