混沌激光布里渊散射的分布式光纤温度传感

Distributed optical fiber temperature sensing based on chaotic light Brillouin scattering

提出一种基于混沌激光布里渊散射的分布式光纤温度传感方法.采用相干长度为88.53 cm的混沌激光作为光源,结合相干域反射技术,利用可变光延迟线调节参考光光程,通过检测传感光纤不同位置的混沌布里渊散射光与参考光的干涉信号,获知整条光纤的温度信息分布.搭建实验系统,研究了注入光功率与偏振态对混沌激光布里渊散射光的特性影响.实验研究待测光纤中固定点的布里渊频移随温度的变化情况,获得1.27℃/MHz的温度系数.在长度为155 m的普通单模光纤上实现空间分辨率为1.2 m的分布式光纤温度传感测量.

We proposed a novel approach to distributed optical fiber temperature sensing based on chaotic laser Brillouin scattering. By utilizing a chaotic light with 88.53 em coherence length as the probe light and the coherent domain reflection technology, and using a rapid variable optical delay line to adjust the reference light path, we measured temperatures by detecting the interference of the back Brillouin scattering light and reference light at different locations along the sensing fiber. We set up an experimental system to investigate the effect of injected optical power and polarization pattern on the performance of the chaotic laser Brillouin scattering, conducted an experimental study on the variation of the Brillouin frequency shift （ BFS ） with temperature, and achieved the temperature coefficient of 1.27 %/MHz and a spatial resolution of 1.2 m for the 155 m standard single-mode optical fiber.