快速预测干扰下斜开孔腔体屏蔽效能的模型

A Model for Quickly Predicting the Shielding Effectiveness of an Enclosure with an Oblique Aperture Under Interference

提出一种针对复杂干扰下斜开孔金属腔体屏蔽效能的计算模型。该模型可快速精准地计算出任意金属材料腔体,任意开孔位置,任意观测点位置,任意入射、极化平面波照射以及斜开孔阵腔体的屏蔽效能。首先依据磁流原理和镜像原理将斜开孔腔体等效为两个水平开孔腔体,然后基于Robinson的等效电路法分别求解各自的屏蔽效能,再利用公式换算求得斜开孔金属腔体的屏蔽效能。随后针对腔体会面临的不同干扰,给出不同情况下屏蔽效能的计算方法。考虑多种干扰叠加的复杂工况,将该模型利用Matlab进行编程,并将计算结果同全波仿真软件CST中的时域传输线矩阵法和频域有限元法的仿真结果进行对比,验证了所提模型的可行性。该模型在保证计算精度的同时,在计算效率上表现出极大的优势。

A calculation method for the shielding effectiveness of an enclosure with an oblique rectangular aperture under complex interference is proposed.This method can quickly and accurately calculate the shielding efficiency of different metal material,off-centered apertures,off-centered observation point position,oblique incidence and polarization and oblique aperture array of enclosures.This enclosure is first decomposed into two ones with horizontal rectangular apertures through mirror image and magnetic flow theories.Then the shielding effectiveness of each decomposed enclosure is solved based on Robinson′s equivalent circuit method.The shielding effectiveness of the metal enclosure with an oblique aperture can be obtained by using the above results to convert through the formula.Finally,the calculation method of shielding effectiveness under different conditions is given for the different interferences that the oblique aperture metal enclosure will face.Considering the complex situation of multiple interference superpositions,by programming the method in Matlab,the results are compared with the simulation results of the time-domain transmission line matrix method and the frequency-domain finite element method in the full-wave simulation software CST.The feasibility of the method in this paper is verified by the comparison results.The method shows great advantages in calculation efficiency while ensuring the calculation accuracy.