A High-Speed Distributed Ultra-Weak FBG Sensing System With High Resolution

作者：Han, Ping; Li, Zhengying; Chen, Liang; Bao, Xiaoyi^*

来源：IEEE Photonics Technology Letters, 2017, 29(15): 1249-1252.

DOI：10.1109/LPT.2017.2712182

• Optical fiber sensing
• ultra-weak fiber Bragg grating
• narrow band filter
• intensity compensation

A high-speed high-resolution distributed sensing system with ultra-weak fiber Bragg grating (FBG) array is presented. The scheme uses a narrow bandwidth filter to translate wavelength shift measurement to a simple intensity measurement. By introducing a reference channel into the system to compensate for the intensity fluctuation from the light source or optical fiber bending loss, we can realize high-resolution and highspeed distributed static and dynamic strain measurement using 342 ultra-weak FBGs with reflectivity of 0.01% and spatial resolution of 2.5 m along 855-m optical fiber. The wavelength variation of all gratings was measured as 0.22 pm at a sampling rate of 100 kHz. Experimental results show that the resolution of strain measurement can achieve 222 ne, and dynamic frequency of 2000 Hz is achieved.

• 出版日期2017-8-1
• 单位武汉理工大学