Analysis and reduction of electromagnetic field leakage through loaded apertures

In this work, we propose the use of resistive sheets (lossy material) to reduce electromagnetic penetration and improve the shielding effectiveness of enclosures with apertures. The resistive material is applied in several configurations that are discussed in this paper. It is found that significant reduction of electromagnetic leakage is possible by using loading techniques inspired by the transmission line interpretation of current distribution on apertures at or beyond resonance. Furthermore, we show that using the configurations proposed in this work, it is possible to achieve significant reduction in the near and far field aperture radiation without affecting airflow area. Numerical results are presented using the finite difference time domain (FDTD) method.