WU Xin,
XUE Guo-Qiang,
XIAO Pan et al
.2017.Noise reduction technology of TEM using optimization of instrument sampling function.Chinese Journal Of Geophysics,60(9): 3677-3684,doi: 10.6038/cjg20170931
1. Key Laboratory of Electromagnetic Radiation and Detection Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China; 2. Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China; 3. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract：The bipolar synchronous sampling method is widely used for noise reduction in Transient Electromagnetic Measurement (TEM). If the noise could be recognized satisfied as the assumption of statistical stationery, this method would be effective theoretically. However, in practice the ability of this method is limited. In this paper, we propose an improved method for optimization of the Instrument Sampling Function (ISF) to enhance the noise reducing ability of the system. A Gauss function is designed and used as a window function for the corresponding gate function to improve the high frequency noise reducing ability and another Gauss function filtered by a notching filter is designed and used as a window function for the weighting function in order to improve the industrial noise reducing ability. Finally we compared the results of data processing with the different instrument sampling functions before and after the optimization. The results prove that this new method has stronger ability in noise reduction for TEM measurement than the traditional bipolar synchronous sampling method.
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