The measurement of shielding effectiveness for small-in-size ferrite-based flat materials

Abstract

This work presents the results of our studies on the electromagnetic interference shielding effectiveness ofsmall-in-size samples of ferrite composition microwave absorber prepared by using the ceramic method. The shieldingeffectiveness measurement was performed using the complex intrinsic parameters of the material. The coaxial holdermethod with the well-known test technique based on transmission/reflection measurements was used in the experimentalsetup. Complex intrinsic parameters were measured in the frequency range of 2–18 GHz by using the Nicholson–Ross–Weir (NRW) method with an automated test setup. First, the shielding effectiveness was measured by conventional testmethod and then it was calculated using complex intrinsic parameters with the NRW method. Comparison was madebetween measured and calculated SEs. By using a new method the SE was determined as a function of the complexintrinsic parameters of materials ϵ , µ, and frequency. This method is preferred in order to provide higher accuracy indetermining material electromagnetic shielding effectiveness for small-in-size materials. For the first time, the shieldingeffectiveness of small-sized samples has been measured in the frequency range between 2 and 18 GHz by using the NRWmethod.