CAJ | 학술논문

电磁脉冲干扰是大地电磁测深系统（M T ）信号的主要噪声之一，严重影响后续视电阻率和阻抗的计算及目标信息的提取。针对脉冲类噪声在时间域中的变化特征，利用经验模态分解（EMD）对脉冲类电磁噪声进行压制处理。首先，对大地电磁信号经EMD分解后得到 N个本征模态函数（IM F）；然后，对每一阶的IM F选择一个合适的阀值，对于该IM F中超出该阀值的部分进行截断；最后，进行EM D重构。实测数据测试表明：改正后信号能量损失小，与改正前信号相关性高，可有效地抑制脉冲类噪声干扰。
전자맥충간우시대지전자측심계통（M T ）신호적주요조성지일，엄중영향후속시전조솔화조항적계산급목표신식적제취。침대맥충류조성재시간역중적변화특정，이용경험모태분해（EMD）대맥충류전자조성진행압제처리。수선，대대지전자신호경EMD분해후득도 N개본정모태함수（IM F）；연후，대매일계적IM F선택일개합괄적벌치，대우해IM F중초출해벌치적부분진행절단；최후，진행EM D중구。실측수거측시표명：개정후신호능량손실소，여개정전신호상관성고，가유효지억제맥충류조성간우。
As one of the main noise interferences of the magnetotelluric sounding system (M T ) , like-impulse electromagnetic noise not only affects the count of subsequent apparent resistivity and impedance , but also badly influences the target information extraction . In this paper ,we briefly introduced the basic principles and algorithms of the empirical mode decomposition method (EMD) ,and based on the analysis of actual data ,we discussed its application in magnetotelluric signal processing and noise suppression .First ,we can get intrinsic mode function (IMF) after EMD decomposition from magnetotelluric signal ;then ,select a suitable threshold for each of the IM F and truncated the excess part ;last ,did EMD reconstruction .Test results of field data show that corrected signal is of high correlation coefficient and less energy loss compared with raw signal , and is a high accuracy approximation of raw signal .T he like-impulse noise of field data can be restrained efficiently .