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Echo Particle Image Velocimetry
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Noise-proof inversion of lidar equation
Optics Letters
|September 10, 2009
Summary
This study introduces a new method to stably solve the lidar equation for atmospheric transmittance, even in optically thick conditions. The technique effectively recovers attenuation profiles without needing absolute lidar calibration, validated by fog sounding experiments.
Area of Science:
- Atmospheric physics and optics
- Remote sensing technologies
- Laser-based atmospheric monitoring
Background:
- The lidar equation's solution instability poses challenges for atmospheric remote sensing.
- Accurate retrieval of atmospheric properties like attenuation is crucial for climate and weather studies.
- Existing methods often require absolute calibration, limiting their practical application.
Purpose of the Study:
- To investigate the causes of instability in lidar equation solutions.
- To develop an effective method for recovering atmospheric attenuation coefficient profiles and transmittance.
- To enable stable lidar equation solutions for near-horizontal paths without absolute calibration.
Main Methods:
- Analysis of lidar equation solution instability.
- Development of a novel signal processing algorithm for single-frequency lidar data.
- Experimental validation using fog sounding in the atmospheric boundary layer.
Main Results:
- A stable method for retrieving atmospheric attenuation and transmittance from lidar data was developed.
- The method successfully provides stable solutions for near-horizontal sounding paths.
- Experimental tests in fog demonstrate the method's effectiveness and robustness.
Conclusions:
- The proposed method offers a significant advancement in processing lidar data for optically thick atmospheres.
- Elimination of the need for absolute lidar calibration enhances the method's practicality.
- This technique improves the reliability of atmospheric property retrieval using laser sounding.
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