Abstract：A metallic shielding enclosure is generally divided into multiple spatial regions where lots of electronic components are distributed in order to decrease the electromagnetic interference from the adjacent space through apertures.An efficient and accurate analytical model has been developed for the electromagnetic crosstalk from multiple rectangular enclosures connected by metallic plates with rectangular apertures covered by conductive sheets where a circuit boardis put in the upper enclosure, and the shielding enclosure is excited by an electric dipole located in the lower enclosure. This model can give prediction for the coupling between the enclosure and the circuit board. The electromagnetic fields from the lower enclosure into the upper one through the covered aperture on the plate are calculated by using the dyadic Green’s function and the boundary condition of a sheet with infinite extension against a plane wave of normal incidence, then the shielding effectiveness (SE) of the target point is calculated in combinationof the electromagnetic topology (EMT) theory and the BLT (Baum-Liu-Tesche) equation.Comparison with the full wave simulation software CST has verified the model over a wide frequency band. Finally, the analytical model is employed to analyze the effect of different factors includingthe conductivity of the conductive sheet, the thickness, the positionand the quantity of the circuitboard, and the position of the electric dipole on the SE of the enclosure. The analytical model can calculate the SE fast and efficiently, and much less memory utilization compared with numerical methods.
郝建红, 公延飞, 蒋璐行, 范杰清. 内置电路板的复杂多腔体电磁串扰屏蔽效能的解析研究[J]. 电工技术学报, 2018, 33(3): 670-679.
Hao Jianhong, Gong Yanfei, JiangLuhang, Fan Jieqing. Analytical Formulation for the Shielding Effectiveness of Electromagnetic Crosstalk from a Complex Multiple Enclosures with Inner Circuit Board. Transactions of China Electrotechnical Society, 2018, 33(3): 670-679.
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2018, Vol. 33 
