Analysis for shielding effect of metal plate with apertures with FDTD

Aperture arrays for airflow in an enclosure can become the coupling path of electromagnetic interference (EMI) from the interior to the external environment. The FDTD (finite-difference time-domain) is a versatile computation technique for simulation of electromagnetic radiation in EMC analysis. Herein, the FDTD is applied to investigate the shielding effect (SE) of a metal plate with aperture arrays. The factors such as the size and shape of aperture, sum of apertures, the thickness of the metal plate are studied to see how they act on the SE. The numerical results and the measurement agree well. Some of the empirical conclusion will benefit the practical design.