Electromagnetic Shielding Analysis of Spherical Polyhedral Structures Generated by Conducting Wires and Metallic Surfaces

The shielding performance of novel spherical polyhedral structures illuminated by an electromagnetic plane wave is investigated. The spherical shield screens consist of a juxtaposition of wire conductors and planar metallic elements distributed according to the regular pattern of a spherical polyhedron. The considered 3-D screens represent four groups of structures with fundamental elements of design for attaining frequency selectivity. It is shown that at low frequency, the wire frame screen provides high levels of shielding effectiveness, while its counterpart of metallic surfaces has a similar behavior for higher frequency bands. Moreover, the shielding characteristics of a combined wire-surface and wire-loop spherical surface are reported and compared with the cases of a single screen of wire conductors or metallic surfaces. The reported numerical results illustrate the advantage of using each configuration. Detailed physical interpretations of the obtained numerical results are given based on the operation mechanism of spherical shield structures according to structural-based and pattern-based resonances.