In this paper the measurement of conductive emi emission is discussed , and the design of cm / dm discrimination network is also presented , further , the performance of insertion loss ( il ) and common - mode rejection ( cmr ) is researched , together with the test approach and experiment results 摘要分析了传导性电磁干扰信号的测量方法,提出基于共模差模( cm / dm )信号的识别网络设计,进一步研究了模态识别网络的插入损耗( il )及共模抑制比( cmr )等重要性能,并给出模态识别网络的性能实验设计与分析方法。