Fabian Happ

An extension of Schelkunoff's shielding theory to anisotropic conducting multilayer materials

A wave matrix formulation that describes the coupling through a planar shield of several anisotropic conducting layers is presented in detail. The approach includes all multiple reflections inside the different layers of the shield. The resulting wave matrix can be used to calculate the shielding effectiveness of the shield. As a result it is demonstrated that for specific cases the shielding effectiveness of an anisotropic multilayered shield can be approximated by the shielding effectiveness of an isotropic shield. In addition a finite structure is simulated and it is shown that the method for the infinite structure allows to correctly predict the transition from isotropic to anisotropic shielding effectiveness with respect to frequency.

Numerical Shielding Analysis of Anisotropic Multilayer Materials by the Method of Moments

In this contribution, an efficient method is developed to calculate the shielding effectiveness of anisotropic conducting multilayer materials by the method of moments. An analytical solution is used to approximate the wave propagation inside the multilayer material. This solution is coupled with a method of moments implementation, allowing to numerically calculate the electromagnetic fields in exterior and interior regions of a shield. Obtained results are compared to those of alternative numerical techniques and form the basis to validate the modeling of anisotropic multilayer materials by a homogeneous material of equivalent conductivity.