Nuclear magnetic resonance FID signal noise suppression method based on multilinear singular value tensor decomposition

Abstract

The invention provides a nuclear magnetic resonance FID signal noise suppression method based on multilinear singular value tensor decomposition, and the method comprises the steps: obtaining a multi-channel signal: enabling one channel to start sampling at an interval of delta t through delay sampling, and obtaining the multi-channel signal; converting each channel signal into a Hankel matrix, forming a third-order tensor, performing Tucker decomposition and processing on the third-order tensor to obtain a third-order tensor, recovering the third-order tensor into a multi-channel signal, performing CP tensor decomposition processing on a second-order tensor X formed by the multi-channel signal, and finally obtaining a high signal-to-noise ratio signal xnew after fusion of multiple communication signals. The method has the advantages that the limitation of a current algorithm under strong noise interference is effectively overcome, meanwhile, the instantaneity and universality of the algorithm are guaranteed, the method can be suitable for instruments such as a proton magnetometer and a nuclear magnetic resonance water exploration instrument, the frequency domain measurement precision and the hydrological parameter accuracy of the instruments are improved, and the precision and accuracy of related geosciences are effectively improved.

Description

technical field [0001] The invention relates to the field of signal processing, in particular to a multi-linear singular value tensor decomposition nuclear magnetic resonance FID signal noise suppression method and method. Background technique [0002] Free induction decay (Free induction decay, FID) signal is a signal generated in nuclear magnetic resonance technology. ) all obtain the required geomagnetic field value, hydrological parameters, etc. by extracting the parameters of the nuclear magnetic resonance FID signal, frequency measurement, and hydrological parameter inversion. However, the obtained FID signals are extremely weak, and the FID signal is easily drowned. In environmental noise and man-made noise. Therefore, how to suppress various types of noise has become the main limitation of nuclear magnetic resonance technology in related geoscience instruments. Therefore, in order to improve the measurement precision and accuracy of geoscience instruments, it is ne...

AI Technical Summary

Problems solved by technology

[0003] The current FID signal noise suppression method mainly uses algorithms for noise suppression. Commonly used algorithms include SVD, wavelet transform, PCA, EMD and other algorithms, but these algorithms still have the following limitations in practical applications: 1) Data volume requirements Higher, when the number of sampling points is small, the noise suppression effect will be greatly reduced; 2) Analysis and processing in the time-frequency domain has a large amount of computation, and real-time performance cannot be guaranteed;

[0004] 3) The universality is weak. These algorithms perform noise suppression for specific types of noise, but in actual situations, there will be multiple noises at the same time.

Therefore, when the obtained FID signal is noisy and has many types of noise, these algorithms are almost unable to perform effective noise suppression, making the instrument unable to work normally

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