Abstract Apertures and slots of the enclosures come into prominence for heat allocation, ventilation, I/O cable, etc. These slots and apertures induce the coupling route of electromagnetic interference (EMI) from the inside to outside. So, electromagnetic shielding is usually used to decrease the emissions or to the progress of equipment immunity. In this paper, an effect of an aperture shape on the performance of electrical shielding effectiveness has been investigated by means of simulation. Rectangular, square, circular, equilateral triangle and hexagonal shape apertures that have a constant area of 5625 mm2 have been studied in addition to polarization type of applied electromagnetic field. It has been observed that ESE depends on the electric field direction and plane wave polarization and rectangular shape aperture has more effective ESE performance than square, circular, equilateral triangle and hexagonal type apertures. Rectangular shaped aperture has approximately 43 dB better performance than equilateral triangle one for whole frequency band of 100 MHz to 1GHz. Rectangular, square, circular, hexagonal and equilateral triangle type apertures have been ranked from best performance to the worst with respect to their ESE. There have been considerable findings that can be useful for enclosure designers about the effect of angle of incidence and polarization angle.

中文翻译：

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孔径形状、入射角和极化对金属外壳屏蔽效能的影响

摘要 外壳的开孔和缝隙在热量分配、通风、输入/输出电缆等方面发挥了重要作用，这些开孔和缝隙引起了电磁干扰（EMI）从内到外的耦合路径。因此，电磁屏蔽通常用于减少辐射或提高设备抗扰度。在本文中，通过仿真研究了孔径形状对电屏蔽效能性能的影响。除了应用电磁场的极化类型之外，还研究了恒定面积为 5625 mm2 的矩形、正方形、圆形、等边三角形和六边形孔。据观察，ESE 取决于电场方向和平面波极化，矩形孔径比方形、圆形、等边三角形和六边形孔径具有更有效的 ESE 性能。对于 100 MHz 至 1GHz 的整个频带，矩形孔径的性能比等边三角形孔径高约 43 dB。矩形、方形、圆形、六边形和等边三角形类型的孔径在 ESE 方面从最佳性能到最差排名。关于入射角和偏振角的影响，已经有相当多的发现对外壳设计人员很有用。对于 100 MHz 至 1GHz 的整个频带，矩形孔径的性能比等边三角形孔径高约 43 dB。矩形、方形、圆形、六边形和等边三角形类型的孔径在 ESE 方面从最佳性能到最差排名。关于入射角和偏振角的影响，已经有相当多的发现对外壳设计人员很有用。对于 100 MHz 至 1GHz 的整个频带，矩形孔径的性能比等边三角形孔径高约 43 dB。矩形、方形、圆形、六边形和等边三角形类型的孔径在 ESE 方面从最佳性能到最差排名。关于入射角和偏振角的影响，已经有相当多的发现对外壳设计人员很有用。