Directional hybrid FEM-MoM for automotive system level simulation

Electromagnetic compatibility (EMC) issues are becoming increasingly important for the automotive industry. An accurate system level analysis is required from an early design stage for optimal performance. The major difficulty encountered in automotive simulation is to deal with different geometric scales, ranging from fraction of wavelengths to multiple wavelengths. In many cases, a domain decomposition method using Finite Element Method (FEM) and Method of Moments (MoM) may be effective by computing each domain separately and stitching them together using equivalent boundary currents. However, when the problem size becomes larger, this method loses its efficacy as calculation of domain interactions become computationally costly. In this paper a new method is proposed for multi-domain problems in EMC radiation emission (RE) test, based on the fact that when two domains are electrically far apart, the back scattered field from the receiving antenna to DUT is quite minimal and can be neglected. The proposed method demonstrates a substantial reduction in memory requirements and computational time when compared to traditional multi-domain hybrid FEM-MoM with acceptable accuracy.