Strain sensing method based on the combination of phase demodulation and cross-correlation in OFDR

作者：Yan-Lin Liu, Qin Yu, Hongwei Zhang, Wanyu Zhao, Jitao Cao, Feng Wang · 年份：2025 · DOI：10.1117/12.3084084 · 研究领域：Advanced Fiber Optic Sensors、Optical Coherence Tomography Applications、Magneto-Optical Properties and Applications

Phase-sensitive optical frequency domain reflectometer (Ф-OFDR) based on all grating fiber measures strain by extracting the phase change of Rayleigh backscattering light in the fibers. However, the stability of this method is severely affected by random phase noise. In this paper, we propose a strain sensing method based on the combination of phase demodulation and the cross-correlation method, which can effectively overcome the problems of insufficient spatial resolution in strain demodulation technology and the influence of phase noise on phase demodulation. When the strain measurement range is 100-500 με, this integration approach achieved a spatial resolution of 0.81 mm and an average root mean square error of 0.32 με. Compared to the measurement error of 16.12 με achieved using phase demodulation alone and the spatial resolution of 1.8 cm obtained using the cross-correlation method alone, this integration approach combines the advantages of both techniques, achieving both high spatial resolution and high measurement accuracy.