EUT对TEM传输室特性阻抗影响的边界元分析

Analysis of the characteristic impedance variation of TEM cell caused by equipment under test by BEM

采用边界元法分析了金属箱体的受试设备对横电磁波传输室特性阻抗的影响 .计算结果表明 ,当受试设备不满足“三分之一准则”时 ,对特性阻抗的影响达 5Ω以上 ,当满足“三分之一准则”时 ,对特性阻抗的影响小于 2Ω .测量结果证实了计算方法的有效性 。

The charcteristic impedance variation of TEM (transverse electromagnetic) cell caused by metallic EUT is analyzed by boundary element method (BEM). The results show that when the EUT (equipment under test) satisfies the 'one-third-area' rule, the characteristic impedance of TEM cell decreases by 2 Ω or less, or else the characteristic impedance will decrease by 5 Ω or more. The calculated results agree well with the measured ones. The results obtained are contributive to TEM cell design and EMC (electromagnetic compatibility) test.