Noise Reduction Method of Φ-OTDR System Based on EMD-TFPF Algorithm

• Published in: IEEE sensors journal Vol. 21; no. 21; pp. 24084 - 24089
• Main Authors: Bai, Yu-Xin, Lin, Ting-Ting, Zhong, Zhi-Cheng
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.11.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Background noise; Data processing; Electromagnetic interference; EMD-TFPF; Exploration; Frequency response; Interference; Noise control; Noise reduction; Optical fiber sensors; Optical fibers; Random noise; Seismic analysis; Sensors; Signal processing algorithms; Signal to noise ratio; SNR; Vibrations; Φ-OTDR
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2021.3107039

The phase-sensitive optical time domain reflectometry (<inline-formula> <tex-math notation="LaTeX">\Phi </tex-math></inline-formula>-OTDR) system has been gradually applied to vertical seismic profile exploration due to its excellent anti-electromagnetic interference, extremely high resolution and sensitivity, and wide detection range. However, the actual data is often disturbed by random noise, which seriously affects the system's ability to recognize low-frequency disturbances. In order to suppress the background noise and improve the signal-to-noise ratio (SNR), a fusion noise reduction method based on empirical mode decomposition and time-frequency peak filtering (EMD-TFPF) algorithm is studied and introduced. In terms of seismic exploration data processing, the algorithm has good denoising performance. Using the <inline-formula> <tex-math notation="LaTeX">\Phi </tex-math></inline-formula>-OTDR system based on optical synchronous reference heterodyne detection as the experimental platform, the EMD-TFPF noise reduction algorithm is applied to the position information and compared with the VSS-NLMS, VMD-NWT and EMD-soft methods. Experimental results show that under the conditions of 0.1 Hz and 5 V vibration interference, the EMD-TFPF method improves the SNR to 37.6 dB, which is much higher than the other three noise reduction algorithms. In addition, this method broadens the low-frequency response range of the system to 10 −5 Hz. The improvement of the system's ability to recognize low-frequency disturbance events will undoubtedly accelerate the practical process of the <inline-formula> <tex-math notation="LaTeX">\Phi </tex-math></inline-formula>-OTDR system in seismic exploration.