A Hybrid φ/B-OTDR for Simultaneous Vibration and Strain Measurement  

作　　者：Fei PENG Xuli CAO 

机构地区：[1]Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education), University of Electronic Scienceand Technology of China, Chengdu, 611731, China

出　　处：《Photonic Sensors》2016年第2期121-126,共6页光子传感器（英文版）

基　　金：This work is supported by the National Nature Science Foundation of China （NSFC） under grants （61290312 and 61205048）, the PCSIRT （IRT1218）, and the 111 Project （B14039）.

摘　　要：A hybrid phase-sensitive optical time domain reflectometry （φ-OTDR） and Brillouin optical time domain reflectometry （B-OTDR） system which can realize simultaneous measurement of both dynamic vibration and static strain is proposed. Because the Rayleigh scattering light and spontaneous Brilliouin scattering light are naturally frequency-multiplexed, the heterodyne asynchronous demodulation of frequency shift keying （FSK） in optical fiber communications is utilized, and the demodulations of the two scattering signals are synchronized. In addition, the forward Raman amplification is introduced to the system, which not only makes up for the deficiency of spontaneous BriUiouin scattering based distributed fiber sensor, but also has the merit of the single end measurement of B-OTDR. The designed φ/B-OTDR hybrid system has the sensing range of 49km with 10m spatial resolution. The vibration and strain experiments show that this hybrid system has great potential for use in long-distance structural health monitoring.A hybrid phase-sensitive optical time domain reflectometry （φ-OTDR） and Brillouin optical time domain reflectometry （B-OTDR） system which can realize simultaneous measurement of both dynamic vibration and static strain is proposed. Because the Rayleigh scattering light and spontaneous Brilliouin scattering light are naturally frequency-multiplexed, the heterodyne asynchronous demodulation of frequency shift keying （FSK） in optical fiber communications is utilized, and the demodulations of the two scattering signals are synchronized. In addition, the forward Raman amplification is introduced to the system, which not only makes up for the deficiency of spontaneous BriUiouin scattering based distributed fiber sensor, but also has the merit of the single end measurement of B-OTDR. The designed φ/B-OTDR hybrid system has the sensing range of 49km with 10m spatial resolution. The vibration and strain experiments show that this hybrid system has great potential for use in long-distance structural health monitoring.

关 键 词：Optical fiber sensor Rayleigh scattering Brillouin scattering VIBRATION STRAIN 

分 类 号：TN929.11[电子电信—通信与信息系统] TP391.9[电子电信—信息与通信工程]