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arXiv · 2609.28341

Phase retrieval from a uniformly discrete point set

Jaume de Dios Pont·Josef Greilhuber·Lukas Liehr·Mitchell A. Taylor
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Abstract

We prove that for every window $w$ of the form $w(x) = e^{-π|x|^2} h(x)$, where $h$ is a polynomial, there exists a uniformly discrete set of points $\mathcal{S} \subset \mathbb R^{2d}$ such that the magnitude of the short-time Fourier transform $V_w f$ on $\mathcal{S}$ determines every $f \in L^2(\mathbb R^d)$ up to a constant phase factor. The separation distance can be chosen independent of the degree of $h$ and proportional to the square root of the dimension. The proof combines a discrete norming inequality, based on a multidimensional Remez inequality and VC-dimension bounds, with tail estimates for the reproducing kernel. A formalization of our main result in Lean 4 is also provided.

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Jaume de Dios Pont, Josef Greilhuber, Lukas Liehr, Mitchell A. Taylor. 2026-09-23. Phase retrieval from a uniformly discrete point set. https://arxiv.org/abs/2609.28341

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