Abstract

In the detection process of atmospheric laser absorption spectroscopy in open space, the transmitted beam is inevitably affected by atmospheric turbulence, resulting in superimposed fluctuation noise in the received optical signal. First, the correction method of atmospheric turbulence is theoretically analyzed. In order to reduce the error influence factors and the error transfer coefficient, a new method of spectral data processing based on co-frequency and dual-wave has been proposed. By modifying scintillation noise and background noise, the influence of atmospheric turbulence noise in open space is reduced. An atmospheric detection system in open space based on co-frequency and dual-wave has been established. The experimental results show that the maximum fluctuation of the spectral signal processed by the method of spectrum data processing based on the co-frequency and dual-wave is reduced from 12.854% to 4.635%, and the single-intensity absorbance is fitted by Voigt with its correlation coefficient of 0.9525. The mean of the standard deviation of the algorithm is 0.1370, while the mean value of the standard deviation of the existing algorithm in a short time is 0.6928. And, through the comparative experiment, the standard deviation of the existing data processing techniques of two-wavelength differential absorption is 0.2974, while the standard deviation of the method of spectrum data processing based on the co-frequency and dual-wave is 0.1038. It can be concluded that the co-frequency and dual-wave method can effectively reduce the influence of atmospheric turbulence noise and laser flashing to improve the stability of concentration measurement, which has practical engineering value.

© 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

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References

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2017 (2)

W. W. Ding, L. Q. Sun, and L. Y. Yi, “High sensitive scheme for methane remote sensor based on tunable diode laser absorption spectroscopy,” Acta. Phys. Sinica 66(10), 100702 (2017).

V. A. Kulikov and M. A. Vorontsov, “Analysis of the joint impact of atmospheric turbulence and refractivity on laser beam propagation,” Opt. Express 25(23), 28524–28535 (2017).
[Crossref]

2016 (2)

2015 (2)

C. Liu, L. Xu, J. Chen, Z. Cao, Y. Lin, and W. Cai, “Development of a fan-beam TDLAS-based tomographic sensor for rapid imaging of temperature and gas concentration,” Opt. Express 23(17), 22494–22511 (2015).
[Crossref] [PubMed]

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

2013 (1)

2012 (1)

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

2009 (1)

2007 (1)

2006 (1)

2005 (1)

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

1979 (1)

1978 (1)

1974 (1)

1971 (1)

1967 (1)

Berger, R. H.

Bjerkestrand, A.

Cai, W.

Cao, Z.

Chen, D.

Chen, J.

Chen, J. Y.

Chiba, T.

Cui, X.

Cui, Y. B.

Ding, W. W.

W. W. Ding, L. Q. Sun, and L. Y. Yi, “High sensitive scheme for methane remote sensor based on tunable diode laser absorption spectroscopy,” Acta. Phys. Sinica 66(10), 100702 (2017).

Dong, F.

Dong, F. Z.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Ebert, V.

Elsäßer, W.

Eng, R. S.

Fang, X.

Fried, D. L.

González, R.

Hartmann, S.

Heneghan, J. M.

Homstad, G. E.

Janassek, P.

Kaiser, S.

Kan, R. F.

Keister, M. P.

Kjelaas, A. G.

Klein, A.

Kulikov, V. A.

Laserna, J. J.

Lendl, B.

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Li, H. B.

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

Lin, Y.

Liu, C.

Liu, J. G.

Liu, W. Q.

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

R. F. Kan, W. Q. Liu, Y. J. Zhang, J. G. Liu, M. Wang, D. Chen, J. Y. Chen, and Y. B. Cui, “A high sensitivity spectrometer with tunable diode laser for ambient methane monitoring,” Chin. Opt. Lett. 5(1), 54–57 (2007).

M. Wang, Y. J. Zhang, J. G. Liu, W. Q. Liu, R. F. Kan, T. D. Wang, D. Chen, J. Y. Chen, X. M. Wang, H. Xia, and X. Fang, “Applications of a tunable diode laser absorption spectrometer in monitoring greenhouse gases,” Chin. Opt. Lett. 4(6), 363–365 (2006).

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Lohninger, H.

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Lu, Y. H.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Lucena, P.

Mantz, A. W.

Meffert, C.

Mevers, G. E.

Michel, F.

Molitor, A.

Nordal, P. E.

Ofner, J.

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Pang, T.

Qi, F.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Reidl-Leuthner, C.

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Reyes, R. F.

Schulz, C.

Sigrist, M. W.

Strohbehn, J. W.

Sun, L. Q.

W. W. Ding, L. Q. Sun, and L. Y. Yi, “High sensitive scheme for methane remote sensor based on tunable diode laser absorption spectroscopy,” Acta. Phys. Sinica 66(10), 100702 (2017).

Sun, P.

Tobaria, L.

Todd, T. R.

Tomischko, W.

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Tu, X. H.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Vorontsov, M. A.

Wagner, S.

Wang, L. M.

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

Wang, M.

Wang, S. M.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Wang, T. D.

Wang, X. M.

Wang, Y.

Wang, Y. P.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Wei, Q. N.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Witzel, O.

Wu, B.

Xia, H.

Xie, P. H.

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Xu, L.

Yang, Y.

Yi, L. Y.

W. W. Ding, L. Q. Sun, and L. Y. Yi, “High sensitive scheme for methane remote sensor based on tunable diode laser absorption spectroscopy,” Acta. Phys. Sinica 66(10), 100702 (2017).

Zhang, Y. J.

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

R. F. Kan, W. Q. Liu, Y. J. Zhang, J. G. Liu, M. Wang, D. Chen, J. Y. Chen, and Y. B. Cui, “A high sensitivity spectrometer with tunable diode laser for ambient methane monitoring,” Chin. Opt. Lett. 5(1), 54–57 (2007).

M. Wang, Y. J. Zhang, J. G. Liu, W. Q. Liu, R. F. Kan, T. D. Wang, D. Chen, J. Y. Chen, X. M. Wang, H. Xia, and X. Fang, “Applications of a tunable diode laser absorption spectrometer in monitoring greenhouse gases,” Chin. Opt. Lett. 4(6), 363–365 (2006).

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Zhang, Z.

Zhou, Y.

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

Acta. Phys. Sinica (1)

W. W. Ding, L. Q. Sun, and L. Y. Yi, “High sensitive scheme for methane remote sensor based on tunable diode laser absorption spectroscopy,” Acta. Phys. Sinica 66(10), 100702 (2017).

Appl. Opt. (3)

Atmos. Environ. (1)

C. Reidl-Leuthner, J. Ofner, W. Tomischko, H. Lohninger, and B. Lendl, “Simultaneous open-path determination of road side mono-nitrogen oxides employing mid-IR laser spectroscopy,” Atmos. Environ. 112, 189–195 (2015).
[Crossref]

Chin. Opt. Lett. (2)

J. Opt. Soc. Am. (2)

J. Test Meas. Technol. (1)

F. Z. Dong, W. Q. Liu, J. G. Liu, X. H. Tu, Y. J. Zhang, F. Qi, P. H. Xie, Y. H. Lu, S. M. Wang, Y. P. Wang, and Q. N. Wei, “On-line roadside vehicle emissions monitoring,” J. Test Meas. Technol. 19(2), 119–127 (2005).

Laser Technol. (1)

L. M. Wang, Y. J. Zhang, H. B. Li, Y. Zhou, and W. Q. Liu, “Influence of turbulence on laser absorption spectral signal and its improvement method,” Laser Technol. 36(5), 670–673 (2012).

Opt. Express (5)

Opt. Lett. (1)

Other (3)

R. Z. Rao, Light propagation in the turbulent atmosphere (Anhui Science and Technology, 2005).

J. C. Wyngaard, Turbulence in the Atmosphere (Cambridge University, 2010).

Y. T. Fei, Error Theory and Data Processing(China Machine, 2017).

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Figures (11)

Fig. 1
Fig. 1 Schematic of two-wavelength differential absorption technique at λ1 and λ2.
Fig. 2
Fig. 2 Schematic of co-frequency and dual-wave.
Fig. 3
Fig. 3 The flow chart of the comparison between the two methods.
Fig. 4
Fig. 4 The diagram of the scintillation noise correction algorithm.
Fig. 5
Fig. 5 System construction.
Fig. 6
Fig. 6 The spectral signal before and after the scintillation noise correction. (a) The spectral signal before and after the correction. (b) The figure of the scintillation noise.
Fig. 7
Fig. 7 The background noise correction. (a) The existing method of single absorbance curve. (b) The algorithm of single absorbance curve.
Fig. 8
Fig. 8 The diagram of the standard deviation.
Fig. 9
Fig. 9 The diagram of the concentration distribution.
Fig. 10
Fig. 10 The diagram of allan deviation.
Fig. 11
Fig. 11 The diagram of the measured concentration.

Equations (15)

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I 1 ( λ 1 ,t )= I 01 ( λ 1 ,t )exp( - S * ΦPc( λ 1 ,t )L )exp( - σ 1 ( λ 1 ,t )L )
I 2 ( λ 2 ,t+Δ )= I 02 ( λ 2 ,t+Δ )exp( - σ 2 ( λ 2 ,t+Δ )L )
I 1 ( λ 1 ,t ) I 01 ( λ 1 ,t ) =exp( - S * ΦPc( λ 1 ,t )L ) I 2 ( λ 2 ,t+Δ ) I 02 ( λ 2 ,t+Δ )
c( λ 1 ,t )= 1 S * ΦPL ( ln I 2 ( λ 2 ,t+Δ ) I 02 ( λ 2 ,t+Δ ) ln I 1 ( λ 1 ,t ) I 01 ( λ 1 ,t ) )
σ c( t ) = ( c( t ) I 2 ( λ 2 ,t+Δ ) ) 2 σ I 2 ( λ 2 ,t+Δ ) 2 + ( c( t ) I 02 ( λ 2 ,t+Δ ) ) 2 σ I 02 ( λ 2 ,t+Δ ) 2 + ( c( t ) I 1 ( λ 1 ,t ) ) 2 σ I 1 ( λ 1 ,t ) 2 + ( c( t ) I 01 ( λ 1 ,t ) ) 2 σ I 01 ( λ 1 ,t ) 2    = ( 1 S * ΦPL I 2 ( λ 2 ,t+Δ ) ) 2 σ I 2 ( λ 2 ,t+Δ ) 2 + ( - 1 S * ΦPL I 02 ( λ 2 ,t+Δ ) ) 2 σ I 02 ( λ 2 ,t+Δ ) 2 + ( - 1 S * ΦPL I 1 ( λ 1 ,t ) ) 2 σ I 1 ( λ 1 ,t ) 2 + ( 1 S * ΦPL I 01 ( λ 1 ,t ) ) 2 σ I 01 ( λ 1 ,t ) 2    = 1 S * ΦPL σ I 2 ( λ 2 ,t+Δ ) 2 ( I 2 ( λ 2 ,t+Δ ) ) 2 + σ I 02 ( λ 2 ,t+Δ ) 2 ( I 02 ( λ 2 ,t+Δ ) ) 2 + σ I 1 ( λ 1 ,t ) 2 ( I 1 ( λ 1 ,t ) ) 2 + σ I 01 ( λ 1 ,t ) 2 ( I 01 ( λ 1 ,t ) ) 2
In Pwave: I 1 ( λ 1 ,t )= I 01 ( λ 1 ,t )exp( - S * ΦPc( λ 1 ,t )L )exp( - σ 1 ( λ 1 ,t )L )
In Qwave: I 1 ( λ 2 ,t+Δ )= I 01 ( λ 2 ,t+Δ )exp( - σ 2 ( λ 2 ,t+Δ )L )
c( λ 1 ,t )= 1 S * ΦPL ( ln I 1 ( λ 2 ,t+Δ ) I 01 ( λ 2 ,t+Δ ) ln I 1 ( λ 1 ,t ) I 01 ( λ 1 ,t ) ) = 1 S * ΦPL ln I 1 ( λ 2 ,t+Δ ) I 1 ( λ 1 ,t )
σ c( t ) = ( c( t ) I 1 ( λ 2 ,t+Δ ) ) 2 σ I 1 ( λ 2 ,t+Δ ) 2 + ( c( t ) I 1 ( λ 1 ,t ) ) 2 σ I 1 ( λ 1 ,t ) 2    = ( 1 S * ΦPL I 1 ( λ 2 ,t+Δ ) ) 2 σ I 1 ( λ 2 ,t+Δ ) 2 + ( - 1 S * ΦPL I 1 ( λ 1 ,t ) ) 2 σ I 1 ( λ 1 ,t ) 2    = 1 S * ΦPL σ I 1 ( λ 2 ,t+Δ ) 2 ( I 1 ( λ 2 ,t+Δ ) ) 2 + σ I 1 ( λ 1 ,t ) 2 ( I 1 ( λ 1 ,t ) ) 2
{ E( k )= b 0 + b 1 k+ b 2 k 2  +  b 3 k 3 + b 4 k 4   E( m )=E( k );1kmax( m ) E( n )=E( k )       max( m )kmax( n )+max( m ); and  n=kmax( m )
{ E ( s )= b 0 + b 1 s+ b 2 s 2  +  b 3 s 3 + b 4 s 4     E ( n )=E( s );1smax( n ) E ( m )=E( s )       max( n )smax( n )+max( m ); and m=smax( n )
{ σ x1 ¯ = σ x1 n+m    σ x2 ¯ = σ x2 n+m   p: p = 1 σ x1 ¯ 2 : 1 σ x2 ¯ 2 E( n ) ¯ = E( n )+ E ( n ) p+ p
{ D P ( n )= D P ( n )+ E( n ) ¯ D Q ( m )= D Q ( m )+E( m )
B( n )= a 0 + a 1 n+ a 2 n 2
x(n)= D P ( n ) B( n )

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