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Overlap correction function based on multi-angle measurements for an airborne direct-detection lidar for atmospheric
Optics Express
|April 4, 2024
Summary
This study presents a new method to calculate the lidar overlap function, crucial for accurate atmospheric measurements. The technique uses multi-angle lidar data to correct for near-field effects, improving airborne lidar performance.
Area of Science:
- Atmospheric Science
- Remote Sensing
- Optical Physics
Background:
- Airborne lidar systems are vital for atmospheric profiling.
- Near-field effects, specifically the lidar overlap function, can introduce significant errors in measurements.
- Accurate determination of the overlap function is essential for reliable atmospheric data.
Purpose of the Study:
- To develop and validate a method for estimating the lidar overlap function using multi-angle measurements.
- To correct for near-field effects in airborne nadir-mounted lidar data.
- To assess the temporal evolution of the overlap function for detecting instrument alignment changes.
Main Methods:
- Utilizing multi-angle measurements of atmospheric scenes from airborne lidar.
- Performing regression analysis of logarithm of range-corrected signal versus secant of off-nadir angle for each atmospheric layer.
- Calculating optical depth and backscattering coefficient to determine the overlap correction function.
Main Results:
- The method successfully estimates the lidar overlap function, accounting for near-field effects.
- Optical depth and backscattering coefficients were evaluated for atmospheric layers.
- The derived overlap correction function allows for lidar signals unaffected by the overlap effect.
Conclusions:
- The proposed method is straightforward to implement with scanning lidar capabilities.
- It is applicable in both aerosol-free and aerosol-laden conditions, provided a stable atmosphere.
- The technique can be applied independently to each channel of multichannel lidars.
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