Open AccessContinuous-wave modulation differential absorption lidar system for CO2 measurement
Author(s) -
Hao Liu,
Rong Shu,
Guanglie Hong,
Li Zheng,
Yong Ge,
Yihua Hu
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.104214
Subject(s) - modulation (music) , lidar , laser , optics , absorption (acoustics) , wavelength , frequency modulation , materials science , noise (video) , intensity modulation , intensity (physics) , physics , acoustics , telecommunications , phase modulation , computer science , phase noise , radio frequency , artificial intelligence , image (mathematics)
An intensity modulation hard-target differential laser absorption lidar system for CO2 sensing is demonstrated. On and off wavelength lasers are modulated with 10 kHz and 12 kHz sinusoidal waves. The echo is extracted using coherent detection technique. The system is fiber based, which makes it compact and removable. We obtain three day variation of horizontal column averaged CO2 concentration of Shanghai district. We also propose an accuracy evaluation method based on electronic noise analysis combined with laser frequency modulation. The result shows that the measurement precision for the column corresponds to 3.39×10-6 (rms) with 1s integral time and 450 m path.