基于多波长布里渊光纤激光器的温度传感特性

Temperature sensing characteristics based on multi-wavelength Brillouin fiber laser

为了在高腐蚀、高辐射和强电磁干扰等复杂环境下实现对温度的精确测量,设计并实验了一种基于传感多波长布里渊光纤激光器(MBFL)和参考MBFL的高灵敏度全光纤温度传感器。理论和实验上分析了布里渊散射光的频移与温度变化之间的关系,根据输出斯托克斯激光信号对拍频所得微波信号的频移变化,测量温度的变化。通过带宽为0.1nm的可调谐光滤波器选择第10阶斯托克斯激光信号对输出,并对其进行拍频探测,实现对传感MBFL周围温度变化的精确测量。通过拍频探测第10阶斯托克斯激光信号对,得出其灵敏度为10.829 MHz/℃。当选用第10阶斯托克斯激光信号对进行温度测量时,温度变化40℃的测量误差约为0.138℃。

In order to achieve accurate temperature measurement in complex environments such as high corrosion,high radiation,and strong electromagnetic interference,a high-sensitivity all-fiber temperature sensor based on the sensing multi-wavelength Brillouin fiber laser（MBFL）and reference MBFL was designed and tested.The relation between the frequency shift of Brillouin scattering light and the temperature variation was analyzed theoretically and experimentally,the change in temperature was measured according to the frequency shift of the microwave signal obtained by outputting the Stokes laser signal pair beat frequency.The 10 th-order Stokes pair was injected into a photodetector,which was selected by a tunable optical filter（TOF）with bandwidth of 0.1 nm.Furthermore,the accurate measurement of the temperature around the sensing MBFL could be realized.Results show that the temperature sensitivity is 10.829 MHz/℃through beat frequency detection of 10 th-order Stokes pair.And the measured temperature error is about 0.138 ℃ under the temperature variation of 40 ℃.