采用宽带同轴装置的材料屏蔽效能测试

Testing of Materials Shielding Effectiveness Based on the Broadband Coaxial Test Fixture

为满足现代电子设备高频段检测的需求,研制了一种平面材料屏蔽效能宽带同轴测试装置。通过改变同轴内外径大小,将同轴装置的上限测试频率提高到了6.3 GHz,应用该装置对平面屏蔽材料进行了屏蔽效能频域测试,并与实验室1.6GHz同轴测试装置进行了对比,宽带同轴装置的测试曲线更加趋于"平坦"。对银纤维材料的屏蔽效能进行了测试,表明该装置的测试结果更加逼近于材料实际的屏蔽效能。实验结果表明该装置不仅具有良好的低频性能,同时也提高了测试上限频率,可较为准确地测试导电布,导电膜等电薄材料的屏蔽效能,为评价材料电磁防护能力提供了更为可靠的手段。

In order to meet the requirements of testing the modern electronic device in high-frequency band,a broadband coaxial test fixture is presented for the evaluation of SE（shielding effectiveness） of materials.Experimental results indicate that the return loss of the fixture is less than-20 dB within the range of 0—6.3 GHz.The test fixture is employed for testing the SE of materials in frequency-domain,and the results basically matched with the 1.6 GHz coaxial test fixture of the laboratory.What’s more,the curves measured in the frequency domain become more ＂flat＂.Through the testing of SE of Ag fabric,the results show that the shielding effectiveness curve of the test fixture is closer to the actual material shielding effectiveness.The fixture not only has a good performance in low-frequency band,but also greatly improves the test upper frequency limitation.It can be used for measuring the electrically thin materials,such as conductive cloth and conductive film.The test sample is smaller and the test results are closer to the actual SE of materials.