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arXiv · 2301.00857

Totally Positive Functions and Gabor Frames over Rational Lattices

Karlheinz Gröchenig
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Abstract

We show that for an arbitrary totally positive function $g\in L^1(\mathbb{R} )$ and $\alpha \beta$ rational, the Gabor family $\{e^{2\pi i \beta l t} g(t-\alpha k): k,l \in \mathbb{Z} \}$ is a frame for $L^2(\mathbb{R})$, if and only if $\alpha \beta <1$.

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Karlheinz Gröchenig. 2023-01-02. Totally Positive Functions and Gabor Frames over Rational Lattices. https://arxiv.org/abs/2301.00857

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