仿真方波的大地电磁远参考去噪研究

Simulation of square waveform de-noising research of magnetotelluric with a remote reference

通过给100Ω·m的均匀半空间时间序列添加仿真方波噪声,利用EMTF软件计算得到受影响的视电阻率相位曲线以及带远参考的视电阻率相位曲线,讨论实验噪声对曲线的影响及远参考方法的去噪效果。研究表明,远参考方法能够在一定程度上消除噪声的影响,接近真实的视电阻率相位,而低频低相干度的远参考结果是有偏倚的,为了获得低频阻抗无偏估计,需要参与平均的数据足够大。

Addsimulation square waveform noise to the time series of 100 ohm meteruniform half-space model,calculated the affected apparent resistivity and phase curve by EMTF software as well as the curve calculated with a remote reference to study the influence of noise and the denoising effect of magnetotelluric remote reference method.The research shows that mag-netotelluric remote reference method can eliminate noise to some extent,get the real apparent resistivity and phase curve.But the result of the low frequency with low coherence is biased,in order to obtain unbiased estimation,one need the data involve-dis large enough.