Bragg Phenomena on Metal Plane with Section of Quasiperiodic Spatial Perturbation of Surface Impedance

In this paper we consider phenomena of coupling of wave paraxial beam and quasisurface wave at perfectly conducting plane with segment of spatially oscillating surface impedance. Expansion in spatial harmonics that smoothly vary in longitudinal direction is used for presentation of transversal component of magnetic field. System of integral equations for complex amplitudes of spatial harmonics is obtained. Solutions for current distributions are found by method of moments. Angular patterns of scattering field are evaluated for different angles of incidence. Phenomenon of resonance increasing scattered beam is observed if quasisurface wave is excited. Proposed numeric method has advantages in cases of quasiperiodic structures with large number of "periods"