双层电磁屏蔽织物的组合设计与屏蔽效能研究

Combination Design and Shielding Effectiveness of Double-Layer Electromagnetic Shielding Fabric

织物组合方式影响多层织物的屏蔽效能。选取4种具有不同吸收反射性能、不同结构参数的电磁屏蔽材料,采用法兰同轴法测试单层织物的屏蔽效能,再将不同种类面料的织物以不同的叠放顺序两两组合,测试其屏蔽效能;以单层织物屏蔽效能为基础,分析双层织物屏蔽效能的变化规律,探讨组合方式对多层电磁屏蔽织物屏蔽效能的影响。研究结果表明:在测试频率范围内,相较单层织物,双层织物的屏蔽效能提高了10~40 dB,在2000~3000 MHz频段内比30~1000 MHz频段内提高更多;吸收型双层织物在30~1500 MHz范围内的屏蔽效能峰值大于在1500~2000 MHz范围的,反射型双层织物则相反,即吸收型双层织物屏蔽效能在高频段增幅小于反射型双层织物;双层织物屏蔽效能会因为其叠放顺序不同有所变化,外层反射型面料里层吸收型面料的双层组合屏蔽效能最佳。

Fabric combination mode affects the multi-layer fabric shielding effectiveness.This paper selects four electromagnetic shielding materials with different absorption,reflection performance,and different structural parameters.The flange coaxial method was used to first test the single-layer fabric shielding effectiveness,and then different fabrics were combined in pairs based on fabric type and stacking order,and their shielding effectiveness were tested.Then,the variation rules of double-layer fabric shielding effectiveness was analyzed based on the single-layer fabric shielding effectiveness,and the influence of combination way of the shielding effectiveness of multi-layer electromagnetic shielding fabric was explored.The research results show that,in the test frequency range,the shielding efficiency of double-layer fabric is much improved by30~40 d B,and more better in the range of 2000 to 3000 MHz than the range of 30 to 1000 MHz;the shielding efficiency value of absorption double-bilayer fabric within 30 to 1500 MHz is greater than 1500 to 2000 MHz,that is,the shielding efficiency rate of absorbed double-layer fabric is less than that of reflective double-layer fabric;double-layer fabric shielding effectiveness will be different due to its stacking order,and the combination of the outer layer of reflective fabric and the inner layer of absorbing fabric double-layer shows a best shielding effect.