With the broadband signal, weak signal energy and small magnitude in comparison with the tradition MT, the long-period magnetotelluric survey has a higher data processing requirement. In this paper, the Robust algorithm based on repeated median estimator was applied to long-period magnetotelluric impedance tensor estimates. Compared with the Robust maximum likelihood estimate (M estimate), the repeated median estimator has no need of reset parameters in data processing, and can increase the estimate of the breakdown point up to 50% and get an unbiased estimate of impedance tensor. An application example shows that the Robust algorithm based on repeated median estimator has a strong advantage in the solution of the impedance tensor.
张刚, 王绪本, 张伟, 罗皓中, 罗威. 重复中位数估计Robust算法在长周期大地电磁中的应用[J]. 物探与化探, 2011, 35(6): 813-816,828.
ZHANG Gang, WANG Xu-ben, ZHANG Wei, LUO Hao-zhong, LUO Wei. THE APPLICATION OF Robust ALGORITHM BASED ON REPEATED MEDIAN ESTIMATOR IN THE LONG-PERIOD MAGNETOTELLURIC SURVEY. Geophysical and Geochemical Exploration, 2011, 35(6): 813-816,828.
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