中国物理B ›› 2013, Vol. 22 ›› Issue (7): 74214-074214.doi: 10.1088/1674-1056/22/7/074214

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Influence of laser linewidth on performance of Brillouin optical time domain reflectometry

郝蕴琦a b, 叶青a, 潘政清a, 蔡海文a, 瞿荣辉a   

  1. a Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China;
    b Department of Technology Physics, Zhengzhou University of Light Industry, Zhengzhou 450002, China
  • 收稿日期:2012-10-10 修回日期:2012-12-14 出版日期:2013-06-01 发布日期:2013-06-01
  • 基金资助:
    Project supported by the Science and Technology Commission of Shanghai Municipality (Grant Nos. 2012AA041203 and 13XD1425400), and the Pudong New Area Science and Technology Development Fund, China (Grant No. PKJ2012-D04).

Influence of laser linewidth on performance of Brillouin optical time domain reflectometry

Hao Yun-Qi (郝蕴琦)a b, Ye Qing (叶青)a, Pan Zheng-Qing (潘政清)a, Cai Hai-Wen (蔡海文)a, Qu Rong-Hui (瞿荣辉)a   

  1. a Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China;
    b Department of Technology Physics, Zhengzhou University of Light Industry, Zhengzhou 450002, China
  • Received:2012-10-10 Revised:2012-12-14 Online:2013-06-01 Published:2013-06-01
  • Contact: Cai Hai-Wen, Ye Qing E-mail:hwcai@siom.ac.cn;yeqing@siom.ac.cn
  • Supported by:
    Project supported by the Science and Technology Commission of Shanghai Municipality (Grant Nos. 2012AA041203 and 13XD1425400), and the Pudong New Area Science and Technology Development Fund, China (Grant No. PKJ2012-D04).

摘要: The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewidth of spontaneous Brillouin scattering remains almost constant when the laser linewidth is less than 1 MHz at the same pulse width; otherwise, it increases sharply. A comparison between a fiber laser (FL) with 4-kHz linewidth at 3 dB and a distributed feedback (DFB) laser with 3-MHz linewidth is made experimentally. When a constant laser power is launched into the sensing fiber, the fitting linewidths of the beat signals (backscattered Brillouin light and local oscillator (LO)) is about 5 MHz wider for the DFB laser than for the FL and the intensity of the beat signal is about a half. Furthermore, the frequency fluctuation in the long sensing fiber is lower for the FL source, yielding about 2 MHz less than that of the DFB laser, indicating higher temperature/strain resolution. The experimental results are in good agreement with the numerical simulations.

关键词: Brillouin optical time domain reflectometry (BOTDR), laser linewidth, distributed feedback laser, fiber laser

Abstract: The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewidth of spontaneous Brillouin scattering remains almost constant when the laser linewidth is less than 1 MHz at the same pulse width; otherwise, it increases sharply. A comparison between a fiber laser (FL) with 4-kHz linewidth at 3 dB and a distributed feedback (DFB) laser with 3-MHz linewidth is made experimentally. When a constant laser power is launched into the sensing fiber, the fitting linewidths of the beat signals (backscattered Brillouin light and local oscillator (LO)) is about 5 MHz wider for the DFB laser than for the FL and the intensity of the beat signal is about a half. Furthermore, the frequency fluctuation in the long sensing fiber is lower for the FL source, yielding about 2 MHz less than that of the DFB laser, indicating higher temperature/strain resolution. The experimental results are in good agreement with the numerical simulations.

Key words: Brillouin optical time domain reflectometry (BOTDR), laser linewidth, distributed feedback laser, fiber laser

中图分类号:  (Sensors, gyros)

  • 42.81.Pa
78.35.+c (Brillouin and Rayleigh scattering; other light scattering) 42.55.Wd (Fiber lasers) 42.55.Px (Semiconductor lasers; laser diodes)