| As the electromagnetic shielding fabrics has developed and come into being, it is very important to evaluate shielding effectiveness of them.This paper investigated shielding effectiveness (SE) of electromagnetic shielding fabrics under plane wave by coaxial planar and under electric field source or magnetic field source by electromagnetic shielding enclosure. Analyzing shielding effectiveness of the electromagnetic shielding fabrics can get the reliability of above two methods. These laid a foundation on how to evaluate shielding effectiveness of fabrics. The followings are the main research work in this paper.(1) Firstly, this paper reviewed and analyzed main test methods for shielding effectiveness of electromagnetic shielding materials and summed up the virtues and disadvantages of coaxial planar-main test method for determining shielding effectiveness of electromagnetic shielding fabrics . Put forward a new method ofelectromagnetic shielding enclosure.(2) Having analyzed the shielding principle of electromagnetic shieldingfabrics and the principles of above two test methods.(3) Under plane wave, some value of shielding effectiveness (SE) of electromagnetic shielding fabrics can be got under different frequency and different testing time by coaxial planar fabrics repeatedly .The results of above SE value showed that the frequency doesn't affect the test results. So the coaxial planar has good repeatability. The test results showed increasing while surface resistivity decreasing and are consistent with the shielding principle.(4) The test method of electromagnetic shielding enclosure:For electric field source, while the dimension of window of electromagnetic shielding enclosure is 600mm X 600mm,by testing shielding effectiveness 6 samples, the results showed that all samples have not good repeatability from25MHz to 300MHz and good repeatability from 300 MHz to 3000 MHz.For four samples with stainless steel, (by changing angle of sample with electromagnetic wave), the results showed the angle affects the test effect evidently.For stainless steel fabric, from 1000 MHz to 3000 MHz, by changing the distance between emission antenna and receiving antenna from 1m to 3m, the results showed the distance has affect the test effect evidently.For coated nickel fabric and stainless steel fabric, the results showed the size of sample do affect the test effect evidently;For magnetic field source, all tested samples have no shielding effectiveness.(5) Some effects can be got by comparing coaxial with electromagnetic shielding enclosure. From 30MHz to 1500MHz,the test method of coaxial is good for plane wave and not fit for others. But the electromagnetic shielding enclosure can make up it. It has not good stability from 25MHz to 300MHz and good stability from 300MHz to 3000MHz.(6) This paper discussed the test method of electromagnetic shielding fabrics: first, according to the frequency of fabric shielding, determine reasonable test methods; then, according to the characteristics of radiation, determine reasonable test methods again; finally, determine reasonable the size of sample.Further, this paper discussed improving and developing on the electromagnetic shielding enclosure in the future work.
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