cable屏蔽疑问？做过的高手进来解答一下吧

cable的屏蔽层有如下2种屏蔽层：铝箔&编织网。问一下铝箔和编织网（铜）的区别，铝箔是屏蔽高频电场么？编织网屏 .. T~>#2N-Z  
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引用楼主mark521于2011-04-07 11:47发表的 cable屏蔽疑问？做过的高手进来解答一下吧 : (02g#A`  
cable的屏蔽层有如下2种屏蔽层：铝箔&编织网。问一下铝箔和编织网（铜）的区别，铝箔是屏蔽高频电场么？编织网屏蔽低频电场么？ g:i*O^c@  

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确定一下，你说的是Foil Shielding和Braided Shielding是吗？为什么你认为foil屏蔽高频而braid屏蔽低频？有什么理论可以支持吗？ 2"M
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我个人不做网线，所以我并不确定后面的见解是正确的，仅供你参考。 }td6fj_{  
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两者都是用来做屏蔽的，没有错。以双绞线为例，foil screen既可以用于overall screen也可以用于element screen，braided screen目前只用于overall screen。举例SF/FTP网线（韩国Daetwyler Class F Patch Cable），外层有braided screen和foil screen，每对线还有自己的foil screen。 /(zB0TEd  
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就我目前所知，foil screen的屏蔽效能相对较好，但是铝材料不方便作金工/电子屏蔽端接（mechanical/electrical joint with the end of the shield for shield termination.）[1] z7q%,yw3N  
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Braided screen可以在屏蔽的基础上增强网线的金工强度（mechanical strength），缺点是端接的时候比较耗费人工（the time and effort needed to prepare the cable for attaching a connector.）。[2]
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屏蔽线要求测量Transfer Impedance这个参数，可以参考相关的协议标准。[3][4] X[{\3Av  
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附带一些文献，已经很老了，仅供参考。[5]-[7] -W^2*w   
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Reference *a4 b  
[1] L.O. Hoeft, J.C. Estes, "The role of the drain wire in modern foil cable shields," IEEE Int. Symp. Electromag. Compat., pp.16-19, 9-13 Aug 1993 8A_TIyh?  
[2] "Braided Shield Cable Preparation", Radio Magzine, http://radiomagonline.com/tutorials_tips/radio_braided_shield_cable_2/, accessed on 07 April 2011 qKs7WBRJy  
[3] TIA Standard "Balanced Twisted-Pair Telecomminications Cabling and Components Standards", TIA-568-C.2, Telecommunication Industrial Assossiation, August 2009 8Mb$+^zU  
[4] ISO Standard "Information Technology - Generic Cabling for Customer Premises", ISO/IEC 11801:2002(E), International Standarlization Orgnization, 2002 UJwq n"Q^  
[5] E.F. Vance, "Shielding Effectiveness of Braided-Wire Shields," IEEE Trans. Electromag. Compat., Vol.EMC-17, No.2, pp.71-77, May 1975 6`j<l5-h  
[6] K.S.H. Lee, C.E. Baum, "Application of Modal Analysis to Braided-Shield Cables," IEEE Trans. Electromag. Compat., Vol.EMC-17, No.3, pp.159-169, Aug. 1975 0 r3N^_}  
[7] L.O. Hoeft, J.L. Knighten, "Measured surface transfer impedance of cable shields that use combinations of braid and foil and are used for 1 Gb/s data transfer," IEEE Int. Symp. Electromag. Compat., Vol.1, No., pp.527-531, 24-28 Aug 1998 _z%\
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The Role of the Drain Wire in Modern Foil Cable Shields.pdf (411 K) 下载次数:10 ?>TbTfmR  
Shielding Effectiveness of Braided-Wire Shields.pdf (2262 K) 下载次数:26 opnkmM&[  
Application of Modal Analysis to Braided-Shield Cables.pdf (2479 K) 下载次数:18 Dauo(Uhuo  
Measured Surface Transfer Impedance of Cable Shields that Use Combinations of Braid and Foil and are Used for 1Gbs Data Transfer.pdf (446 K) 下载次数:13

好像在哪看到过一些说法，印象中，要求对电磁波屏蔽的电缆是有两层屏蔽网的，一层单点接地屏蔽电场，一层屏蔽磁场。 JO]`LF]  
觉得铝箔应该是屏蔽电场的，编织网是屏蔽磁场的（因为里面含有铁？），但是屏蔽具体怎么接法不清楚 e(4bx5<*  
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继续关注这个问题！请各位大大们多多指教

恩，看错了……

昨天看的cable的说明，明确说了foil for frequency above 50MHz ,other way, braide for bellow 50MHz.

电缆仿真有人做过吗？数值算法的？

学习了，非常好

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测试频率是多大？ 如果想100%的不辐射，那你的买硬同轴cable了

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