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Fast approximate calculation of multiply scattered lidar returns
1Department of Meteorology, University of Reading, UK. r.j.hogan@reading.ac.uk
Applied Optics
|August 24, 2006
Summary
A new method efficiently calculates multiply scattered lidar returns by grouping photons into zero, one, or more scattering events. This approach significantly speeds up lidar data analysis for applications like cloud profiling.
Area of Science:
- Atmospheric physics and remote sensing.
- Computational physics and numerical methods.
Background:
- Accurate modeling of multiply scattered lidar returns is essential for atmospheric remote sensing.
- Existing methods for calculating higher-order scattering are computationally intensive and limited in order.
Purpose of the Study:
- To develop an efficient approximate method for calculating multiply scattered lidar returns.
- To provide a computationally fast yet accurate alternative for iterative retrieval algorithms.
Main Methods:
- Dividing outgoing photons into three populations based on forward-scattering events (zero, one, and more than one).
- Parameterizing each population at each range gate by energy, spatial variance, directional variance, and covariance.
- Achieving an O(N^2) computational efficiency for an N-point profile, implicitly handling higher-order scattering.
Main Results:
- The new method demonstrates O(N^2) efficiency, significantly outperforming explicit scattering order calculations.
- It provides accuracy comparable to fifth or sixth-order explicit calculations for typical cloud profiles.
- The algorithm is orders of magnitude faster than traditional methods, making it suitable for real-time applications.
Conclusions:
- This efficient approximate method offers a substantial speed improvement for lidar data processing.
- It enables the use of higher-order scattering information in iterative retrieval algorithms, enhancing accuracy.
- The method is ideal for applications requiring rapid analysis of multiply scattered lidar signals.
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