Wave penetration through and reflection from the combined multilayered many-element gratings with dielectric layer and metal screen

A rigorous theory of the combined multilayered many-element cylindrical gratings is presented. The boundary problems are transformed to solving algebraic sets of equations for the multipole coefficients of the spectrum of scattered field. The numerical results for the electrodynamic characteristics of the combined gratings are obtained and analyzed. The combined gratings of various profile and filling with dielectric layers and metal screens are widely used in antenna and microwave engineering as elements of reflecting and matching devices, antenna radomes, microwave resonators and filters, wave transformers etc. To control the transmission, reflection and polarization characteristics of the gratings, it is necessary to provide the capability to change the interior structure of the grating spacing. In this paper, the combined multilayered many-element cylindrical gratings are suggested and investigated to provide this capability. A rigorous theory of combined multilayered many-element circular cylindrical gratings is proposed, and some numerical results are obtained and discussed