Acceleration of shielding effectiveness analysis using stable FDTD subgridding

Abstract

Even though it is desirable to fully shield computer components from external electromagnetic field, this cannot be done due to the need for ventilation. The finite-difference time-domain (FDTD) method can be used to analyze the shielding effectiveness of a computer enclosure with apertures. The multiscale nature of this problem calls for the use of a locally refined grid (subgridding), which however can compromise FDTD stability. We present a systematic approach to create provably-stable FDTD subgridding schemes and investigate their ability to accelerate the assessment of shielding effectiveness.