1 武汉理工大学光纤传感技术国家工程实验室, 湖北 武汉 430070
2 武汉理工大学信息工程学院, 湖北 武汉 430070
基于时分复用技术，提出了一种分布式弱光纤光栅（FBG）阵列振动探测系统。通过匹配干涉仪检测相邻弱FBG的干涉信号，可以得到振动信号的频率、相位和位置等相关信息，从而实现高灵敏度分布式测量。使用3×3相位解调方法对干涉信号进行解调，可以有效地降低系统的相位噪声。采用光栅个数为660、间距为2.5 m的弱FBG阵列对该系统进行了验证。实验结果表明，系统的干涉条纹可见度与相邻弱FBG的波长差有关；同时，系统能准确地分辨出不同频率的信号，频率响应范围在20~1000 Hz之间，具有很好的频率响应；与标准的地震检波器对比发现，该系统传感单元具有更高的灵敏度。
传感器 光纤光栅传感 弱光栅阵列 匹配干涉仪
Author Affiliations
Abstract
1 National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan 430070, China
2 Key Laboratory of Fiber Optic Sensing Technology and Information Processing, Ministry of Education, Wuhan University of Technology, Wuhan 430070, China
A field-programmable gate array (FPGA)-based large-capacity sensing network with ultra-weak fiber Bragg gratings (FBGs) is proposed and experimentally studied. The demodulation system is constructed to interrogate 1642 serial time-division-multiplexing FBGs with a peak reflectivity of about 40 dB and equal separations of 2.5 m. Two semiconductor optical amplifiers and an InGaAs linear sensor array controlled by an FPGA are introduced to the demodulation system to achieve fast, precise, and flexible interrogation. The low crosstalk and spectral distortion are investigated through both theoretical analysis and experiments.
060.3735 Fiber Bragg gratings 250.5980 Semiconductor optical amplifiers 060.4230 Multiplexing Chinese Optics Letters
2016, 14(1): 010601
Author Affiliations
Abstract
1 National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan, 430070, China
2 Key Laboratory of Ministry of Education for Fiber Optic Sensing Technology and Information Processing, Wuhan University of Technology, 430070, China
A time division multiplexing of 106 weak fibers Bragg gratings (FBGs) based on a ring resonant-cavity is demonstrated. A semiconductor optical amplifier is connected in the cavity to function as an amplifier as well as a switch. The 106 weak FBGs are written along a SMF-28 fiber in serial with peak reflectivity of about -30 dB and equal separations of 5 m. The crosstalk and spectral distortion are investigated through both theoretical analysis and experiments.
Fiber Bragg grating (FBG) semiconductor optical amplifier (SOA) time-division multiplexing (TDM) Photonic Sensors
2016, 6(2): 132
Author Affiliations
Abstract
National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan,
This paper reviews the work on huge capacity fiber-optic sensing network based on ultra-weak draw tower gratings developed at the National Engineering Laboratory for Fiber Optic Sensing Technology (NEL-FOST), Wuhan University of Technology, China. A versatile drawing tower grating sensor network based on ultra-weak fiber Bragg gratings (FBGs) is firstly proposed and demonstrated. The sensing network is interrogated with time- and wavelength-division multiplexing method, which is very promising for the large-scale sensing network.
Ultra-weak FBG Ultra-weak FBG optical fiber sensors optical fiber sensors sensing network sensing network Photonic Sensors
2016, 6(1): 26
Author Affiliations
Abstract
1 National Engineering Laboratory of Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan, 430070, China
2 China Three Gorges University, Yichang, 443002, China
An interrogation system based on two semiconductor optical amplifiers for weak fiber Bragg gratings (FBGs) was proposed. The first semiconductor optical amplifier (SOA) was used to modulate the light, and the second SOA separated the reflected signal from the different FBGs through delayed switching. The proposed system has lower insertion loss and higher spatial resolution, and can interrogate the time- and wavelength-division multiplexed FBG array. Up to 50 FBGs, with a reflectivity of 0.2% and a spatial resolution of 5 m along the optical fiber, were distinguished to demonstrate the interrogation system.
Fiber Bragg grating sensors time-division multiplexing semiconductor optical amplifiers interrogation Photonic Sensors
2014, 4(2): 168
武汉理工大学 光纤传感技术中心,湖北 武汉 430070
提出一种在多模光纤上腐蚀制作出法布里-珀罗(F-P)腔体,并将该F-P腔体和一根普通通信单模光纤熔接起来构成微型非本征型光纤F-P干涉(EFPI)应变传感器的方法。实验结果证明这种结构的干涉传感器对结构的微小应变有着极高的灵敏度,可达到0.00095 nm /με,而且对温度的交叉敏感较小。这种制备工艺简单、重复性高、易于批量加工的光纤应变传感器件在光传感领域,特别是对各种建筑结构健康状况的远程监测中具有较大的潜在应用价值。
光纤光学 光纤传感 F-P 干涉腔 远程监测
