ANALYSIS OF TRANSMISSION GRATINGS BY METHOD OF FINITE-ELEMENTS

A new numerical technique is presented for the analysis of diffraction of horizontally and vertically polarized waves by an array of conducting cylinders with arbitrary elemental cross-section, commonly known as transmission gratings. The method, which is based on the finite-element technique, is simple in nature and involves no iterative calculations. Numerical results are obtained for gratings of rectangular and circular elements for both polarizations at arbitrary angles of incidence. These results compare favorably with the experimental and theoretical data available in the literature. They further reveal some interesting properties of transmission gratings. The proposed technique is also applicable to a large class of problems in electromagnetics and physics.