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arXiv · 2501.07799

Atomic Norm Soft Thresholding for Sparse Time-frequency Representation

Zongyue Yang·Baoqing Ding·Shibin Wang·Chuang Sun·Xuefeng Chen
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Abstract

Time-frequency (TF) representation of non-stationary signals typically requires the effective concentration of energy distribution along the instantaneous frequency (IF) ridge, which exhibits intrinsic sparsity. Inspired by the sparse optimization over continuum via atomic norm, a novel atomic norm soft thresholding for sparse TF representation (AST-STF) method is proposed, which ensures accurate TF localization under the strong duality. Numerical experiments demonstrate that the performance of the proposed method surpasses that of conventional methods.

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Zongyue Yang, Baoqing Ding, Shibin Wang, Chuang Sun, Xuefeng Chen. 2025-01-14. Atomic Norm Soft Thresholding for Sparse Time-frequency Representation. https://arxiv.org/abs/2501.07799

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