Author Affiliations
Abstract
1 Guizhou Power Grid Information and Communication Company, Guizhou, 550003, China
2 Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education), University of Electronic Science and Technology of China, Chengdu, 611731, China
In order to enhance the signal-to-noise-ratio of a distributed acoustic sensing system based on phase-sensitive optical time-domain reflectometry (Φ-OTDR), we have proposed a combination of segmented unwrapping algorithm, averaging estimation of phase difference, and infinite impulse response (IIR) filtering method. The enhancement of signal quality is numerically demonstrated. Moreover, we have studied the influence resulted from the light source noise on the Φ-OTDR performance. The result has shown that when the linewidth of light source used in the Φ-OTDR system is narrower, the performance of the system is better. In a word, such a Φ-OTDR system could obtain higher quality demodulated signals when the narrower linewidth light source is chosen and the method of averaging estimation phase difference is used.
Phase unwrap Phase unwrap frequency filter frequency filter phase noise phase noise Photonic Sensors
2016, 6(1): 58
淮阴师范学院 物理与电子电气工程学院, 江苏 淮安 223300
基于椭圆形光强分布光栅投影测量物体三维面形的方法, 将椭圆形光强分布光栅投影到被测物体表面, 用摄像机获取变形条纹图, 通过系统参量和条纹图携带的相位信息求解出物体的三维面形.推导出通过椭圆形光强分布光栅条纹求解相位的计算公式并对提出方法作了计算机仿真.实验结果表明该方法可以比较准确地测量物体的三维面形,在噪音较大的情况下测量结果仍具有较高准确度.
三维测量 椭圆形光强分布光栅 条纹分析 相位展开 3D measurement Elliptic pattern grating Fringe analysis Phase unwrap
