Design of meanderline polarizer based on modal technique

Abstract

In the modal technique for the analysis of multilayered structures, a generalized S-matrix description of each infinite, periodic, metallic screen is obtained by the Floquet mode expansion moment method. These S-matrices are then cascaded together with those of the intervening dielectric layers to form an overall S-matrix. At the input plane of the polarizer, the electric field vector of a linearly polarized incident plane of the polarizer, the electric field vector of a linearly polarized incident plane wave is inclined at 45 degrees to the meanderline line axis so that either a TE (transverse electric) or a TM (transverse magnetic) mode is present. The polarizer then provides the necessary coupling between or conversion into the TE and TM modes so that, at the output plane, a circularly polarized wave exists, consisting of a TE00 and TM00 mode, all other modes being evanescent. The S-matrix of the layered structure describes this mode conversion. By attaching an optimizer to the analysis module, a synthesis program is obtained. The dimensions of the meanderline within the cell, the cell periodicities, and the thickness of the supporting layers are manipulated to provide low axial ratio and good match over a range of frequencies and incident angles.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>