A hybrid method for shielding effectiveness estimation of a perforated enclosure against planewave excitation

摘要

This paper develops a hybrid model based on the combination of full-wave simulation method and circuit model analytic algorithm, which can predict the shielding effectiveness of a perforated rectangular enclosure irradiated by a planewave with arbitrary incident and polarization direction. In order to take the effect of the electromagnetic losses of the aperture into account, the full-wave simulation method is adopted to calculate the coupling voltage of the aperture. The circular aperture or rectangular aperture with arbitrary length-width ratio can be positioned anywhere in the front panel of the enclosure. Taking the effect of the thickness into account, we establish the equivalent circuit model of the perforated enclosure with aperture coupling voltage as an equivalent voltage source. Then, the TEmn and TMmn modes of the coupling electric field at arbitrary observation point within the enclosure are calculated based on waveguide theory. Simulation results of the hybrid model are in good agreement with those of transmission line matrix method within the frequency range of 0-3 GHz. Solution times using the hybrid model are far less than those required by pure numerical methods.