Polynomial Chaos Based Statistical Analysis of the Shielding Effectiveness of an Enclosure With Apertures Under Multiple Uncertainties

This article presents an efficient statistical analysis of the shielding effectiveness (SE) of an enclosure with apertures under multiple uncertainties. It takes full advantage of the high efficiency of an extended equivalent circuit model and the versatility of the polynomial chaos theory to investigate the propagation mechanism of uncertainties from random input parameters to the SE. The uncertainties arising from fabrication tolerance and increasingly complex electromagnetic environment effects are embodied as parameters that follow Gaussian or uniform distributions. Important physical effects such as mutual coupling of apertures, propagation of higher-order modes, penetration of obliquely incident and arbitrarily polarized plane wave, and loading effect of dielectric plate are all taken into account to keep in line with practical scenario. Sensitivity analysis has been performed to investigate the influence of each random input parameter to the SE. A surrogate model has been established with expansion coefficients computed by using the stochastic Galerkin method and the stochastic collocation method. The results of the deterministic calculation and the statistical computation are validated by using the transmission-line matrix method in a commercial software and Monte Carlo simulation respectively.