Gabor phase retrieval is severely ill-posed
نویسندگان
چکیده
The problem of reconstructing a function from the magnitudes its frame coefficients has recently been shown to be never uniformly stable in infinite-dimensional spaces [5]. This result also holds for frames that are possibly continuous [2]. On other hand, is always finite-dimensional settings. A prominent example such phase retrieval recovery signal modulus Gabor transform. In this paper, we study and ask how stability degrades on natural family subspaces domain $L^2(\mathbb{R})$. We prove constant scales at least quadratically exponentially dimension subspaces. Our construction shows typical priors as sparsity or smoothness promoting penalties do not constitute regularization terms retrieval.
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ژورنال
عنوان ژورنال: Applied and Computational Harmonic Analysis
سال: 2021
ISSN: ['1096-603X', '1063-5203']
DOI: https://doi.org/10.1016/j.acha.2019.09.003