volume | PIER Journals

Abstract

This article focuses on the low-frequency magnetic shielding of double-layer conducting plates with periodic circular apertures. The shielding effectiveness (SE) is measured as the insertion loss of the plates when they are placed between a pair of coaxial loops, one for magnetic field emission and the other for receiving. Our experimental results show that the SE sharply increases with the layer-to-layer spacing increasing from zero to the aperture diameter. For aluminum plates with 1 mm thickness, 20 mm unit cell and 10 mm aperture diameter, the enhancement is approximately 10 dB and 20 dB for 3 mm and 9 mm spacing, respectively. In addition, the effect of the lateral deviation on the SE is evident only if the spacing is smaller than the aperture diameter.

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Dr. Feiyan Zhou

Dr. Yan Wu

Dr. Lingyun Gu

Dr. Xuefeng Bai

Dr. Yan Wu

Dr. Yang Wang

Dr. Dingyu Qin

Professor Chongqing Jiao