Susceptibility analysis of arbitrarily shaped 2-D slotted screens using a hybrid generalized scattering matrix finite-element technique

The electromagnetic susceptibility (EMS) inside slotted screens has been studied using a hybrid technique. The screen is characterized by a generalized admittance or impedance matrix, computed using the finite element method (FEM), which is then combined with a modal solution in free-space. The scattering matrix for the screen can then be easily computed. As a practical application, the electrical performance of a slotted square envelope has been studied. In general, it is shown that coupling to the interior of slotted screens is maximized at frequencies corresponding to resonances of the shorted screen, provided that the fields do not vanish near the aperture.