title: SVD-Based Technique for Interference Cancellation and Noise Reduction in NMR Measurement of Time-Dependent Magnetic Fields.
abstract: A nuclear magnetic resonance (NMR) experiment for measurement of time-dependent magnetic fields was introduced. To improve the signal-to-interference-plus-noise ratio (SINR) of NMR data, a new method for interference cancellation and noise reduction (ICNR) based on singular value decomposition (SVD) was proposed. The singular values corresponding to the radio frequency interference (RFI) signal were identified in terms of the correlation between the FID data and the reference data, and then the RFI and noise were suppressed by setting the corresponding singular values to zero. The validity of the algorithm was verified by processing the measured NMR data. The results indicated that, this method has a significantly suppression of RFI and random noise, and can well preserve the FID signal. At present, the major limitation of the proposed SVD-based ICNR technique is that the threshold value for interference cancellation needs to be manually selected. Finally, the inversion waveform of the applied alternating magnetic field was given by fitting the processed experimental data.
authors.affiliation: School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China. chenwj1025@hust.edu.cn.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Chen
authors.affiliation: School of Electronics Information and Communication, Huazhong University of Science and Technology, Wuhan 430074, China. mahong@hust.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.affiliation: School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China. yude@hust.edu.cn.
authors.forename: De
authors.initials: D
authors.lastname: Yu
authors.affiliation: School of Electronics Information and Communication, Huazhong University of Science and Technology, Wuhan 430074, China. zhanghua@hust.edu.cn.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
keywords: interference cancellation; magnetic field measurement; noise reduction; singular value decomposition; time-dependent magnetic fields