Filtering characteristics of thin, planar 3D printed element arrays

Periodic arrays of metallic elements have been popular in printed antenna designs for the past two decades. For these applications the elements are individually excited and the array factor is the primary design consideration, affecting directly the radiation pattern characteristics of the array. Therefore, in these applications, the element lattice and excitation distribution is of primary importance, while the interelement separations are usually kept electrically large, of the order of half-substrate wavelength. Viewing such geometries as filtering devices, has not been examined in detail. For these applications, the structure operates passively, the excitation of the elements being created by an external incident field and not subject to controlled design. The response of the structure, under these conditions, can have very interesting filtering characteristics and can be the subject of optimum design provided the corresponding EM scattering has been solved. We focus on these aspects of these arrays, and we probe the question of optimizing this response, as a function of the critical dimensions of the printed elements.