Abstract:In consideration of the nonlinear, non-stationary and non-minimum phase characteristics of the magnetotelluric signal, this paper has proposed a denoising method based on empirical mode decomposition and wavelet transform, in which the time series signal is decomposed by EMD transform, the continuous mean square error criteria are used to determine a turning point in the original signal energy, then the wavelet threshold denoising method is employed to denoise the residual amount of intrinsic mode function, and finally the signal is reconstructed. Tests of signal processing show that the method can be effectively applied to signal denoising process.
罗皓中, 王绪本, 张伟, 罗威, 张刚. 基于经验模态分解法与小波变换的长周期大地电磁信号去噪方法[J]. 物探与化探, 2012, 36(3): 452-456.
LUO Hao-zhong, WANG Xu-ben, ZHANG Wei, LUO Wei, ZHANG Gang. AN IMPROVED DENOISING METHOD FOR LONG-PERIOD MAGNETOTELLURIC SOUNDING BASED ON EMD AND WAVELET TRANSFORMATION. Geophysical and Geochemical Exploration, 2012, 36(3): 452-456.
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