On the Practical Use of Blaschke Decomposition in Nonstationary Signal Analysis

Ronald R. Coifman; Hau-Tieng Wu

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arXiv · 2508.10861

On the Practical Use of Blaschke Decomposition in Nonstationary Signal Analysis

Ronald R. Coifman·Hau-Tieng Wu

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Abstract

The Blaschke decomposition-based algorithm, {\em Phase Dynamics Unwinding} (PDU), possesses several attractive theoretical properties, including fast convergence, effective decomposition, and multiscale analysis. However, its application to real-world signal decomposition tasks encounters notable challenges. In this work, we propose two techniques, divide-and-conquer via tapering and cumulative summation (cumsum), to handle complex trends and amplitude modulations and the mode-mixing caused by winding. The resulting method, termed {\em windowed PDU}, enhances PDU's performance in practical decomposition tasks. We validate our approach through both simulated and real-world signals, demonstrating its effectiveness across diverse scenarios.

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BibTeX RIS

Ronald R. Coifman, Hau-Tieng Wu. 2025-08-14. On the Practical Use of Blaschke Decomposition in Nonstationary Signal Analysis. https://arxiv.org/abs/2508.10861

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