A Noise Suppression Method for NMR Sounding FID Signals

Abstract

The invention relates to a method for suppressing noise of nuclear magnetic resonance sounding FID signals. The method includes the following steps: performing frequency spectrum analysis on the signal detected by the magnetic resonance sounding system, using normalized orthogonal detection technology to decompose the detected signal into the same direction component X and the orthogonal component Y, and performing hardware filtering processing to obtain the low frequency The FID signal of the FID signal; the nonlinear energy operator algorithm is used for the collected data to remove the peak noise of the X and Y components in the FID signal; the preliminary signal-to-noise separation of the X and Y components is carried out based on the principal component analysis method; based on the empirical mode decomposition Methods The X and Y components processed by PCA were further decomposed to extract the signal trend item; the X and Y components processed by EMD were superimposed and averaged to obtain the e-exponential curve. The present invention completely abandons the problems that traditional filtering means easily cause loss of signal components, etc., and realizes effective suppression of various complex noises contained in nuclear magnetic resonance sounding FID signals.

Description

technical field [0001] The invention relates to signal processing in the field of nuclear magnetic resonance, in particular to a noise suppression method for nuclear magnetic resonance sounding FID signals based on principal component analysis and empirical mode decomposition. Background technique [0002] Magnetic resonance sounding (Magnetic resonance sounding, MRS), as a geophysical method to directly detect groundwater, uses the relaxation characteristics of hydrogen protons in water to detect groundwater, and has been used in groundwater exploration, hydrogeological survey and landslide stability. It has been applied in evaluation, dam leakage, old empty water detection in coal mines and advanced detection and early warning of water inrush in tunnels. With the advancement of science and technology, after more than ten years of development, the instrument systems that have been commercialized include the NUMIS system, NUMISplus system, and NUMISpoly system of the French ...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a noise suppression method for nuclear magnetic resonance sounding FID signal, aiming at providing a brand-new modern filtering method to suppress the noise of nuclear magnetic resonance sounding FID signal, so as to solve the problem of nuclear magnetic resonance sounding under strong electromagnetic interference. Efficient Extraction of Deep Signals

Images