首页 > 论文 > 光谱学与光谱分析 > 36卷 > 6期(pp:1794-1798)

采用小波分析方法降低可调谐半导体激光吸收光谱技术测量下限的实验研究

The Experimental Research on Reducing the Minimum Measureable Limit of Tunable Diode Laser Absorption Spectroscopy with Wavelet Analysis

  • 摘要
  • 论文信息
  • 参考文献
  • 被引情况
  • PDF全文
分享:

摘要

基于可调谐激光吸收光谱技术, 主要采用数据处理的方法如互相关、 小波分析等降低光谱吸收技术的测量下限。 采用可调谐激光吸收光谱技术中的波长调制技术, 对较低浓度下的NH3进行了降低测量下限的试验研究。 采用近红外波段2.25 μm附近的一组ν2+ν3 NH3吸收谱线, 其强度远高于1.5 μm处谱线, 结合波长调制技术在最优信噪比的条件下对常温常压下不同浓度的NH3进行了测量。 为了保证实验条件下测量得到的二次谐波信号的峰值高度达到最大且信噪比最优, 实验在调制系数为2.2左右的情况下, 通过加载最优的高频调制信号来保证信噪比(SNR)。 在10 m长的Herriott池中探测到了浓度为0.6×10-6的二次谐波信号, 其中信号处理部分主要采用相关分析、 多次平均以及小波变换分析来控制中心波长的移动和降低噪音的干扰。 结果表明, 经过数据处理以后的谐波信号, 其检测下限降低到处理前的约百分之一, 且不需要增加任何实验设备就可以很好的抑制噪音的影响, 将相关分析和小波分析与波长调制技术相结合, 这种数据处理方法对于在线检测技术具有很好的实用价值。

Abstract

To obtain the weaker second harmonic signal of low concentration, reduce the minimum measurable limit and improve the sensitivity and accuracy of absorption measurement, a serious of data processing methods are proposed based on tunable diode laser wavelength modulation spectroscopy. The experiment on lower NH3 concentration at 2.25 μm was carried out in a 10.13 m absorption cell with different concentration. The peak height of the second harmonic signal is maximum at m=2.2, which optimizes the signal-to-noise ratio. In order to guarantee the optimal signal-to-noise ratio, the experiment was carried out by loading the optimal high frequency modulation signal. WMS-2f was performed at a repetitive scan rate of 200 Hz and a current-modulation rate of 15 kHz, wavelength modulation spectroscopy with the optimal signal-to-noise ratio was adopted for its better noise immunity to measure different lower NH3 concentration in the Herriott cell. This survey is focused on the ν2+ν3 bands of absorption spectra near 2.25 μm in near-infrared region at ambient temperature and pressure, the line strengths of 2.25 μm are much larger than the absorption lines in the telecommunication bands, using stronger NH3 absorption lines can offer the potential of lower detection limits. During the data processing, the background signal of the original harmonic should be deducted at first, the second harmonic signal of 0.6×10-6 was obtained in a 10 m long-path Herriott cell after data processing, these signal processing mainly consist of cross-correlation analysis, multiple averages and wavelet transform analysis, the cross-correlation analysis was used to control the shift of center wavelength, the multiple averages and wavelet transform analysis were used to reduce influences of the environment noise, after that we get the revised second harmonic signal and improve the accuracy of the measurement results. The experimental results show that these data processing methods can obviously improve the signal quality and reduce the minimum measurable limit about 100 times lower than before. The experiment doesn’t need to add any laboratory equipment and can well restrain the influence of the environmental noise and other disturbance, so these signal process combined with wavelength modulation technique will be more useful for on-line gas detection technology.

投稿润色
补充资料

中图分类号:TN307

DOI:10.3964/j.issn.1000-0593(2016)06-1794-05

基金项目:国家自然科学基金项目(51276165), 高等学校博士学科点专项科研基金项目(20110101110019)资助

收稿日期:2015-04-01

修改稿日期:2015-08-16

网络出版日期:--

作者单位    点击查看

张立芳:浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027
王 飞:浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027
俞李斌:浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027
严建华:浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027
岑可法:浙江大学能源清洁利用国家重点实验室, 浙江 杭州 310027

联系人作者:张立芳(21227023@zju.edu.cn)

备注:张立芳, 1988年生, 浙江大学能源清洁利用国家重点实验室博士研究生

【1】WANG Fei, HUANG Qun-xing, LI Ning, et al(王 飞, 黄群星, 李 宁, 等). Acta Physica Sinica(物理学报), 2007, 56(7): 3867.

【2】Sun K, Chao X, Sur R, et al. Measurement Science and Technology, 2013, 24: 1.

【3】SHAO Jie, GAO Xiao-ming, YUAN Yi-qian, et al(邵 杰, 高晓明, 袁怿谦, 等). Acta Physica Sinica(物理学报), 2005, 54(10): 4638.

【4】MAO Yu-wen, TU Ya-qing, XIAO Wei, et al(毛育文, 涂亚庆, 肖 玮, 等). Journal of Vibration and Shock(振动与冲击), 2012, 31(21): 112.

【5】Reid J, Labrie D. Applied. Physics. B-Lasers and Optics, 1981, 26: 203.

【6】WANG Jian, Maiorov M, Jeffries J B, et al. Measurement Science and Technology, 2000, 11: 1576.

【7】HAO Lü-yuan, WU Guo-rong, SHI Qiang, et al(郝绿原, 吴国荣, 史 强, 等). Chinese Journal of Chenical Physics(化学物理学报), 2001, 14(2): 147.

【8】Chao Xing, Jeffries J B, Hanson R K. Proceedingsof the Combustion Institute, 2013, 34: 3583.

【9】XIA Hua, DONG Feng-zhong, TU Guo-jie, et al(夏 滑, 董凤忠, 涂郭结, 等). Acta Optica Sinica(光学学报), 2010, 30(9): 2596.

【10】ZHOU Wei(周 伟). MATLAB Wavelet Analysis Advanced Technology(MATLAB小波分析高级技术). Xi’an: Xidian University Press(西安: 西安电子科技大学出版社), 2005. 87.

【11】PAN Quan, ZHANG Lei, MENG Jin-li, et al(潘 泉, 张 磊, 孟晋丽, 等). Wavelet Filtering Method and Application(小波滤波方法及应用). Beijing: Tsinghua University Press(北京: 清华大学出版社), 2005. 63.

引用该论文

ZHANG Li-fang,WANG Fei,YU Li-bin,YAN Jian-hua,CEN Ke-fa. The Experimental Research on Reducing the Minimum Measureable Limit of Tunable Diode Laser Absorption Spectroscopy with Wavelet Analysis[J]. Spectroscopy and Spectral Analysis, 2016, 36(6): 1794-1798

张立芳,王 飞,俞李斌,严建华,岑可法. 采用小波分析方法降低可调谐半导体激光吸收光谱技术测量下限的实验研究[J]. 光谱学与光谱分析, 2016, 36(6): 1794-1798

您的浏览器不支持PDF插件,请使用最新的(Chrome/Fire Fox等)浏览器.或者您还可以点击此处下载该论文PDF