Research on Compensation Algorithm of Three Axis Gradient Aeromagnetic Prospecting System
WU Peilin①②③ ZHANG Qunying①③ LI Guang①②③ LIU Lihua①③ FANG Guangyou①③
①(Key Laboratory of Electromagnetic Radiation and Sensing Technology, Chinese Academy of Sciences, Beijing 100190, China) ②(University of Chinese Academy of Sciences, Beijing 100049, China) ③(Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China)
Abstract：Aeromagnetic prospecting is an important method in geophysical prospecting for its high-efficiency and convenience. In the paper, a new kind of the three axis gradient system based on the unmanned helicopter is designed and an aeromagnetic compensation method based on the neural network is proposed. The system is equipped with four Optically Pumped Magnetometers (OPMs), from which the three axis gradient data can be achieved. In aeromagnetic compensation, the feedforward network is used. The Improvement Ratio (IR) of the three axis gradient data is 15.2, 4.7 and 5.9, respectively. The Peak Signal to Noise Ratio (PSNR) of the three axis gradient data is improved by 17.1 dB, 6.5 dB and 6.5 dB, respectively. Through the result of the Cross Calibration Index (CCI), the generalization ability of the method is good. The three axis gradient system and the aeromagnetic compensation are proven valid in aeromagnetic prospecting by an experiment.
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