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Homotopy Methods Based on $l_{0}$ -Norm for Compressed Sensing
IEEE Transactions on Neural Networks and Learning Systems
|February 18, 2017
Summary
This study introduces two homotopy methods for compressed sensing (CS), improving upon iterative hard thresholding (IHT) by automating regularization parameter selection. These methods efficiently generate accurate sparse solutions, even with noisy data.
Area of Science:
- Signal Processing
- Numerical Analysis
- Optimization
Background:
- Compressed Sensing (CS) enables signal recovery from fewer measurements than traditional methods.
- Iterative Hard Thresholding (IHT) is a common algorithm for CS, but sensitive to regularization parameter choice.
- Determining optimal regularization parameters is crucial for effective CS recovery.
Purpose of the Study:
- To develop novel homotopy methods for solving the compressed sensing problem.
- To address the challenge of selecting regularization parameter values in IHT.
- To enhance the accuracy and efficiency of sparse signal recovery in CS.
Main Methods:
- Proposed two homotopy methods integrating the homotopy technique with Iterative Hard Thresholding (IHT).
- Analyzed the theoretical properties of the proposed methods, including convergence and sparsity bounds.
- Modified the methods into heuristic algorithms to improve solution quality.
Main Results:
- Demonstrated that accumulation points of the generated sequences are feasible solutions.
- Established an upper bound on the sparsity level for solutions.
- Computational experiments confirmed the effectiveness of the heuristic algorithms.
Conclusions:
- The proposed homotopy methods effectively solve the compressed sensing problem.
- The heuristic algorithms provide accurate and efficient sparse solutions, robust to noisy observations.
- These methods offer a practical advancement for compressed sensing applications.
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