Electromagnetic wave diffraction by flat semi-infinite strip grating

The electromagnetic (EM) wave reflection by a flat semi-infinite grating (SIG) of metal strips is studied using the operator method. The full-wave specral method is applied for the key problem of diffraction by a single strip. The nonlinear equation is termas of the operator of reflection from SIG has been built. The anlytic form of reflected field in the case of the plane wave incidence and thin SIG has been built. The analytic form of reflected field in the cases of the plane wave incidence and thin SIG of narrow strips has been obtained by the steepest-descent method. This solution is anylysed from the physical point of view and compared with alternative accurate integral representation of field reflected from thin SIG.