An efficient and accurate hybrid model has been developed for the electromagnetic leakage from two apertured cascaded metallic rectangular enclosures connected by a metallic plate with an aperture covered by a non-magnetic conductive sheet excited by an electric dipole located in the enclosure. The leakage fields through the covered aperture are derived by using the dyadic Green's function and employing the approximate boundary conditions at both sides of the sheet which is regarded as an infinite conductive plate. Then, the leakage fields into the external space through the aperture regardless of its thickness at the end of the enclosure are derived based on a generalization of the method of moments (MoM). Finally, the shielding effectiveness (SE) at the target points outside the enclosure is calculated for the intermediate analysis of the leakage fields. Comparison with the full wave simulation software CST has verified the model over a wide frequency band. The hybrid model then is employed to analyze the effect of different factors including the thickness and the conductivity of the conductive sheet on the SE, and the corresponding physical mechanisms of the leakage fields are also illuminated. The hybrid model can also be extended to deal with other cases, including the whole plate made of non-magnetic conductive material without apertures, the infinite thickness of the aperture at the end of the enclosure, and the aperture at the end of the enclosure is also covered by a non-magnetic conductive sheet.
2. Henry, W. O., "Electromagnetic Compatibility Engineering," Wiley Interscience, 2009.
3. Gomory, F., et al., "Experiment realization of a magnetic cloak," Science, Vol. 335, No. 6075, 1466-1468, 2012.
4. Araneo, R. and G. Lovat, "An efficient MoM formulation for the evaluation of the shielding effectiveness of rectangular enclosures with thin and thick apertures," IEEE Trans. Electromagn. Compat., Vol. 50, No. 2, 294-304, 2008.
5. Robinson, M. P., et al., "Analytical formulation for the shielding effectiveness of enclosures with apertures," IEEE Trans. Electromagn. Compat., Vol. 40, No. 240, 240-248, 1998.
6. Hao, J.-H., P.-H. Qi, J.-Q. Fan, and Y.-Q. Guo, "Analysis of shielding effectiveness of enclosures with apertures and inner windows with TLM," Progress In Electromagnetic Research M, Vol. 32, 73-82, 2013.
7. Tharf, M. S. and G. I. Costache, "A hybrid finite element-analytical solutions for in-homogeneously filled shielding enclosures," IEEE Trans. Electromagn. Compat., Vol. 36, No. 4, 380-385, 1994.
8. Bethe, H. A., "Theory of diffraction by small holes," Phy. Rev. II, Vol. 66, No. 7 and 8, 163-182, 1944.
9. Nitsch, J., S. Tkachenko, and S. Pottast, "Pulsed excitation of resonators," Interaction Note, Note 619, 2010.
10. Anderieu, G., et al., "Homogenization of composite panels from a near-field magnetic shielding effectiveness measurement," IEEE Trans. Electromagn. Compat., Vol. 54, No. 3, 700-703, 2012.
11. Chen, M.-D., X.-H. Xie, and H.-Y. Zhang, "Simulation and calculation of the absorbing microwave properties of carbon nanotube composite coating," Acta Physica Sinica, Vol. 63, No. 6, 0661031-0661036, 2014.
12. Jiao, C.-Q., "Shielding effectiveness improvement of metallic waveguide tube by using wall losses," IEEE Trans. Electromagn. Compat., Vol. 54, No. 3, 696-699, 2012.
13. Konefal, T., et al., "A fast circuit model description of the shielding effectiveness of a box with imperfect gaskets or apertures covered by thin resistive sheet coatings," IEEE Trans. Electromagn. Compat., Vol. 48, No. 1, 134-144, 2006.
14. Tesche, F. M., M. V. Ianoz, and T. Karlsson, "EMC Analysis Methods and Computational Models," Wiley Inter Science, 1996.
15. Deshpande, M. D., "Electromagnetic field penetration studies," NASA Technical Paper, June 2000.
16. Jiao, C.-Q. and Y.-Y. Li, "Reciprocity principled-based model for shielding effectiveness prediction of a rectangular cavity with a covered aperture," Chinese Physics B, Vol. 24, No. 10, 1041011-1041016, 2015.
17. Dehkhoda, P., A. Tavakoli, and R. Moini, "Shielding effectiveness of a rectangular enclosure with finite wall thickness and rectangular apertures by the generalised modal method of moments," IET Science, Measurement and Technology, Vol. 3, No. 2, 123-136, 2009.
18. Khan, Z. A., et al., "Validation of Modal/MoM in shielding effectiveness studies of rectangular enclosures with apertures," IEEE Trans. Electromagn. Compat., Vol. 48, No. 2, 348-353, 2006.