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arXiv · 2610.30037

Irregular Gabor Frames for the Poisson Kernel

Yurii Belov·Andrei V. Semenov
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Abstract

Consider the semi-regular system of time-frequency shifts of the Poisson kernel $g(t) = {{1} \over {t^2+w^2}}$ $$\G(g, M \times α\Z) = \left\{ e^{2πi λt } g(t-n) \colon (λ, n) \in M \times α\Z \right\}$$ where $M \subset \R$. We obtain {\it a criterion} for $\G(g, M \times α\Z)$ to form a frame in $L^2(\R)$ for an {\it arbitrary} set $M$ of finite upper density. It turned out that the lower density alone does not determine the frame property, even when $M$ is uniformly discrete.

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Yurii Belov, Andrei V. Semenov. 2026-10-21. Irregular Gabor Frames for the Poisson Kernel. https://arxiv.org/abs/2610.30037

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