[EMC仿真]【pdf】【631k】利用有限元法分析EMC暗室的NSA

利用有限元法分析 EMC暗室的 NSA $YX{
gk>  
孟东林 , 沙 　 斐 'u<e<hU  
(北京交通大学电子与信息工程学院电磁兼容实验室 ,北京 100044) G^Gs/- f  
m~&  
摘 　 要: EMC 暗室是最常用的电磁兼容测试场地 ,常受限于低频性能。为了在建造 EMC 暗室之前 ,对其低频性能作准确的预测分析 ,利用平面分层等效模型来模拟暗室中的角锥吸波体 ,研究了暗室的不同墙面铺设不同吸波材料时其性能的变化情况。仿真结果表明 ,适当增加钝口吸波体的高度能够显著改善暗室性能;在暗室 4 个墙位置中 ,处于第一菲涅尔区的侧墙(与电波传播方向平行)位置的吸波材料更加关键。实测数据的验证 ,表明上述方法分析暗室低频性能时准确可靠。 6RbDc*  
eaFkDl  
关键词: 电波暗室; 射线追踪法; 归一化场地衰减; 吸波体; 有限元法; 电磁兼容 r)|~Rs!y,  
v8-My1toV  
中图分类号: TM935 ; U285 文献标志码: A 文章编号: 100326520 (2007) 0920041205 W+i^tmj  
9;L4\  
基金资助项目: 北京交通大学 “十五” 重大科技专项基金项目资助(DXJ04002) 。 YcA. Bn|as  
XN<!.RCw  
Project Supported by Key Science and Technology Foundation of Beijing Jiaotong University During t he 10t h Five2year Plan (DXJ04002) . %!\=$s}g  
Analysis of NSA of Anechoic Chamber with FEM MEN G Dong2lin , SHA Fei ( EMC Lab , School of Elect ronic and Information Engineering ,Beijing J iaotong Univer sity , Beijing 100044 , China) r^ Dm|^f#  
i?/Q7D<P  
Abstract : An accurate method was int roduced to simulate and analyze normalized site at tenuation (NSA) of anechoicchambers (AC) in the low f requency range (30～100 MHz) with the finite element method ( FEM) . The practical pyramid absorbers were modeled by way of effective permit tivity and planar layers , in order to reduce the mesh size of simulation. Since FEM was good at analyzing high loss , f requency2dependent and anisot ropic media , the FEM was adopted to simulate NSA of ACs , because NSA is a very important criterion for measuring the performance of a semi2AC. The principle , details of simulation , as well as programming flow chart was provided. The reflectivity of two height s of pyramid absorbers was also provided for convenience. Next the effect s of different height s of absorb2 ers lined in different side walls of an AC were studied with this method in order to find the right configuration of ab2 sorbers before const ructing an AC. The simulation result s show that NSA of ACs can be improved by lengthening pyramid absorbers. The absorbers in the first Fresnel zone are key to ACs ; thus it s performance can be improved just by optimize the absorbers in this zone. Finally , the simulation result s are v .. 'mZv5?  
0i\
>(o  

未注册仅能浏览部分内容，查看全部内容及附件请先 登录 或 注册

好贴就要顶啊~~~~~~~~~~~~~~