34km传感长度的布里渊光时域反射计的设计与实现

布里渊分布式光纤传感器是目前最具应用前景的分布式光纤传感技术之一,其关键是如何检测布里渊散射光信号,布里渊光时域反射计是其中较好的检测方式。针对布里渊散射光信号特点,应用光相干技术来检测布里渊散射光信号。具体采用微波电光调制产生频率可调的参考光,和散射光进行相干检测,根据散射光频移特性,应用电信号处理技术取出布里渊散射光电信号,并采用偏振控制技术来抑制相干检测的偏振相干性,再经过数字信号累加和平均处理,最后得到分布式传感信号。采用光相干检测设计方案实现了布里渊时域反射计分布式光纤传感器,并进行了34km光纤的分布式应变传感实验。

Design and Realization of Briliouin Optical Time Domain Reflectometer with 34km in Sensing Length

Billouin distributed optical fiber sensor is one of the most promising techniques for practical applications,the key is how to detect the Brillouin scattering light,Brillouin optical time domain reflectometer is a good detecting method.Aimed at the scattering light signal's characters of Brillouin optical distributed sensor,a detecting scheme using optical coherent detection was developed.In detail,the scheme adopts electric-optical modulating to produce the frequency-adjustable reference light,which was optical heterodyne detected with the scattering lights.Using electronic processing,Brillouin scattering signal was gained based on Brillouin frequency shift.After accumulation and average,the distributed sensing signal was obtained.Using the optical coherent detection method,Brillouin optical time domain reflectometer has realized,and the distributed stress sensing experiment for 34km fiber was achieved.