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Π-ML: a dimensional analysis-based machine learning parameterization of optical turbulence in the atmospheric surface
Optics Letters
|September 1, 2023
Summary
We developed a physics-informed machine learning model to estimate optical turbulence strength (Cn2) for free-space optical communications. The model accurately predicts Cn2 using normalized variance of potential temperature as a key feature.
Area of Science:
- Physics
- Atmospheric Science
- Optical Engineering
Background:
- Optical turbulence, caused by atmospheric refractive index fluctuations, significantly distorts laser beams.
- Accurate modeling of optical turbulence strength (Cn2) is crucial for reliable free-space optical (FSO) communication systems.
Purpose of the Study:
- To propose a novel physics-informed machine learning (ML) methodology, named Π-ML, for estimating Cn2.
- To identify key atmospheric parameters influencing Cn2 through feature importance analysis.
Main Methods:
- Utilized dimensional analysis and gradient boosting for the ML model.
- Employed an ensemble of models for enhanced statistical robustness.
- Conducted systematic feature importance analysis to identify predictive drivers of Cn2.
Main Results:
- Identified normalized variance of potential temperature as the most dominant feature for predicting Cn2.
- Achieved high out-of-sample performance with an R² value of 0.958 ± 0.001.
- Demonstrated the effectiveness of the Π-ML approach in modeling optical turbulence.
Conclusions:
- The proposed Π-ML methodology provides an accurate and robust method for estimating optical turbulence strength.
- This advancement is vital for the successful development and deployment of future FSO communication links.
- Highlighting the importance of potential temperature variance offers new insights into atmospheric turbulence modeling.
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