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[Application of over sampling sigma-delta A/D in DOAS system]
Su-wen Li1, Wen-qing Liu, Pin-hua Xie
1Key Laboratory of Environmental Optical and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China.
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|March 17, 2007
Summary
Differential optical absorption spectroscopy (DOAS) precision is enhanced by oversampling and sigma-delta analog-to-digital conversion. This technique improves signal-to-noise ratio for accurate trace gas measurements in atmospheric studies.
Area of Science:
- Atmospheric chemistry
- Spectroscopy
- Signal processing
Context:
- Differential optical absorption spectroscopy (DOAS) is crucial for atmospheric trace gas analysis.
- Measurement precision is limited by spectral noise, interfering gases, and signal sampling.
- Current DOAS methods face challenges in achieving high precision.
Purpose:
- Introduce the principles and instrumentation of DOAS.
- Propose an improved measurement technique using oversampling and sigma-delta analog-to-digital conversion (A/D).
- Enhance the signal-to-noise ratio (SNR) for more precise trace gas quantification.
Summary:
- DOAS measures atmospheric trace gases by fitting reference spectra to measurement spectra.
- The study introduces oversampling and sigma-delta A/D technology to mitigate noise.
- This approach restrains quantifying noise and boosts SNR within the measurement band.
Impact:
- Significantly improves the measurement precision of DOAS systems.
- Enables more accurate and reliable atmospheric trace gas monitoring.
- Contributes to advancements in environmental sensing and atmospheric research.
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