Shielding Effectiveness of a Metamaterial Measured at Microwave Range of Frecuency, Known as Wire Screen Metamaterial (Wsm)

Abstract

Abstract-This paper presents the study of an artificial material, made up of a periodic structure, defined by a unit cell, consisting of a finite number N of periodic layers of thin conducting cylinders placed between two dielectric planes. These artificial materials known as metamaterials can be regarded as a homogeneous material with effective constitutive parameters impossible to achieve with naturally occurring materials, such as negative values for both magnetic permeability and electric permittivity. An analytical model has been developed to study the effective electric permittivity of the whole system in terms of the unit cell dimensions and the frequency of the incident electromagnetic wave. Simulations of the effective electric permittivity of the metamaterial were performed by varying the geometry of the metamaterial. This analysis enables the design and construction of structures with properties that make them an attractive candidate for shielding applications in the range of microwave frequencies. The metamaterial has been constructed with four rows of 5 bronze conducting rods each. We have made experimental measurements of the shielding effectiveness of these materials when subjected to a electromagnetic plane wave with electric field polarized along the direction of the conducting rods, and conversely, with electric field polarized perpendicular to the rods. Non-zero values for shielding effectiveness were observed in the first polarization, and zero values in the second case.

Using Homogeneous Equivalent Parameters in Finite Element Models of Curved Metamaterial Structures

“…Applications of metamaterials include information and communications technology, and security, medical, and radar imaging, to name a few [1][2][3]. As it pertains to the shielding from microwave interference, it is the ability to make planar metamaterials that exhibit near 100% absorption at a specific frequency or frequencies that makes them a viable shielding option [4][5][6]. Many different configurations of electromagnetic metamaterials have been fabricated and tested, and some examples are split-ring resonators [7][8][9], circular fishnet designs [10], resistive film arrays [11], and conductive square arrays [12][13][14].…”