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The Impact of Different Kernel Functions on the Performance of Scintillation Detection Based on Support Vector
1Departments of Electronics and Telecommunications, Politecnico di Torino, 10129 Torino, Italy.
Sensors (Basel, Switzerland)
|December 5, 2019
Summary
Support Vector Machines (SVM) effectively detect ionospheric scintillation affecting Global Navigation Satellite Systems (GNSS) signals. Fine Gaussian SVM offers superior accuracy for scintillation detection, outperforming other kernel functions.
Area of Science:
- Space Physics
- Signal Processing
- Machine Learning
Background:
- Ionospheric scintillation, caused by electron density irregularities, disrupts Global Navigation Satellite Systems (GNSS) signals.
- This disruption severely impacts GNSS receiver performance in signal acquisition, tracking, and positioning.
- Machine learning algorithms are increasingly applied for detecting and mitigating scintillation effects.
Purpose of the Study:
- To evaluate the performance of Support Vector Machines (SVM) for detecting ionospheric scintillation.
- To analyze the impact of different SVM kernel functions (linear, Gaussian, polynomial) on detection accuracy.
- To determine the optimal kernel function selection for reliable scintillation detection.
Main Methods:
- Utilized real-world GNSS signal data affected by scintillation from SANAE IV (Antarctica) and Hanoi (Vietnam).
- Implemented and compared SVM algorithms with linear, Gaussian (coarse, medium, fine), and third-order polynomial kernels.
- Statistically assessed performance using probabilities of detection and false alarm rates, considering data preparation and cross-validation.
Main Results:
- Fine Gaussian SVM demonstrated superior overall accuracy compared to linear and other Gaussian kernels.
- The third-order polynomial kernel showed improved performance over linear and coarser Gaussian kernels.
- Linear SVM exhibited the lowest complexity and fastest running time.
Conclusions:
- SVM is a viable machine learning approach for ionospheric scintillation detection using GNSS signals.
- Fine Gaussian SVM provides the best accuracy, while linear SVM offers computational efficiency.
- Kernel function selection involves a trade-off between detection accuracy and computational complexity.
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