单激光源布里渊光学时域放大系统的光路结构

Optical network of Brillouin optical time domain amplifier system with a single laser

提出了一种单激光源的布里渊光学时域放大(BOTDA)系统的光路结构,只需用到1台激光器,且扫频范围由高频微波频率(约11 GHz)降为中短波频率(MHz),节省了成本。建立了相应的实验系统,将传感光纤置于温控箱中进行实验,获取了布里渊散射信号随温度变化的实验数据。推导出传感光纤两端入射光频差恒定时布里渊散射信号与温度间服从洛伦兹分布的规律,对实验数据进行了洛伦兹曲线拟合,结果表明系统光路可行。

The optical network of a Brillouin optical time domain amplifier（BOTDA） system is proposed,in which only one laser source is used and the frequency scan range is decreased from the high frequency microwave（about 11 GHz） to the intermediate wave（MHz） without any frequency-shift locking device for cost saving.The experiment system was set up with the sensing fiber in the temperature controller,and the temperature-dependent Brillouin scattering signal was achieved.It is deduced that the Brillouin scattering signal and temperature obey Lorenz distribution when the frequency difference between incident light waves at two ends of the sensing fiber keeps constant.The Lorenz curve fitting was done for the test data and results show that the optical network is feasible.