Swept optical SSB-SC modulation technique for high-resolution large-dynamic-range static strain measurement using FBG-FP sensors
Swept optical SSB-SC modulation technique for high-resolution large-dynamic-range static strain measurement using FBG-FP sensors
复制标题
DOI：
10.1364/ol.40.001406
复制
发表时间：
2015-04-01
期刊：
影响因子：
3.6
通讯作者：
Li, Fang
中科院分区：
文献类型：
--
作者：
Huang, Wenzhu;Zhang, Wentao;Li, Fang
本文介绍了一种使用抑制载流子LiNbO3 （LN）光单边带（SSB-SC）调制器的FBG-FP传感器的静态应变解调技术。利用线性啁啾信号驱动调制器产生窄线宽可调谐激光源。然后将该可调谐单频激光器用于FBG-FP传感器的pdd技术，该技术有利于消除调制器在不同调谐频率下光强波动的影响。通过计算传感FBG-FP传感器与参考FBG-FP传感器之间PDH信号的波长差来解调静态应变。实验结果表明，与商用pzt可调谐激光器相比，该调制器的时频响应线性度（R-2）从0.989提高到0.997，扫频范围（动态范围）从数百MHz提高到几GHz。调制器的高线性时间-波长关系可以有效地解决扫频非线性问题，有利于提高应变测量分辨率。在实验室测试中，证明了0.67纳米应变静态应变分辨率，动态范围为6 GHz。(C) 2015美国光学学会
This Letter presents a static strain demodulation technique for FBG-FP sensors using a suppressed carrier LiNbO3 (LN) optical single sideband (SSB-SC) modulator. A narrow-linewidth tunable laser source is generated by driving the modulator using a linear chirp signal. Then this tunable single-frequency laser is used to interrogate the FBG-FP sensors with the Pound-Drever-Hall (PDH) technique, which is beneficial to eliminate the influence of light intensity fluctuation of the modulator at different tuning frequencies. The static strain is demodulated by calculating the wavelength difference of the PDH signals between the sensing FBG-FP sensor and the reference FBG-FP sensor. As an experimental result using the modulator, the linearity (R-2) of the time-frequency response increases from 0.989 to 0.997, and the frequency-swept range (dynamic range) increases from hundreds of MHz to several GHz compared with commercial PZT-tunable lasers. The high-linearity time-wavelength relationship of the modulator is beneficial for improving the strain measurement resolution, as it can solve the problem of the frequency-swept nonlinearity effectively. In the laboratory test, a 0.67 nanostrain static strain resolution, with a 6 GHz dynamic range, is demonstrated. (C) 2015 Optical Society of America