Modeling the performance of direct-detection Doppler lidar systems including cloud and solar background variability
M J McGill1, W D Hart, J A McKay
1Laboratory for Atmospheres, Code 912, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA. mcgill@virl.gsfc.nasa.gov
Applied Optics
|March 8, 2008
Summary
This study introduces a realistic atmospheric model for spaceborne Doppler lidar systems, improving wind measurement accuracy. Simulations show minimal daytime performance degradation with proper solar filtering.
Area of Science:
- Atmospheric science
- Remote sensing
- Optical engineering
Background:
- Previous spaceborne Doppler lidar performance models used idealized atmospheric conditions.
- Realistic atmospheric variability, including clouds and aerosols, is crucial for accurate simulations.
Purpose of the Study:
- To develop a novel technique for modeling spaceborne direct-detection Doppler lidar performance in a realistic atmosphere.
- To assess the impact of atmospheric variability and solar radiance on daytime wind measurement accuracy.
Main Methods:
- Developed a new atmospheric model based on airborne lidar observations, incorporating cloud and aerosol variability.
- Simulated daytime performance using measured solar radiance data that varied with viewing scene.
- Evaluated two direct-detection Doppler lidar techniques (double-edge and multichannel) at 355 nm for Rayleigh wind measurement.
Main Results:
- The new model accounts for atmospheric variability absent in previous simulations.
- Daytime wind measurement uncertainty is only slightly degraded (10-20%) compared to nighttime.
- The inclusion of a proper solar filter is critical for maintaining performance.
Conclusions:
- Realistic atmospheric modeling significantly enhances the fidelity of spaceborne Doppler lidar simulations.
- Direct-detection Doppler lidar systems demonstrate robust daytime wind measurement capabilities with appropriate instrument design.
- This work provides a more accurate basis for the design and deployment of future spaceborne wind-sensing missions.
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