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Related papers: Frame set for Gabor systems with Haar window

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We investigate vector-valued Gabor frames (sometimes called Gabor superframes) based on Hermite functions $H_n$. Let $h= (H_0, H_1, ..., H_n)$ be the vector of the first $n+1$ Hermite functions. We give a complete characterization of all…

Functional Analysis · Mathematics 2010-12-21 Karlheinz Gröchenig , Yurii Lyubarskii

We study the existence of Gabor orthonormal bases with window the characteristic function of the set W=[0,a] U [b+a, b+1] of measure 1, with a, b>0. By the symmetries of the problem, we can restrict our attention to the case a<=1/2. We…

Classical Analysis and ODEs · Mathematics 2017-04-11 Elona Agora , Jorge Antezana , Mihail N. Kolountzakis

We show that $(g_2,a,b)$ is a Gabor frame when $a>0, b>0, ab<1$ and $g_2(t)=({1/2}\pi \gamma)^{{1/2}} (\cosh \pi \gamma t)^{-1}$ is a hyperbolic secant with scaling parameter $\gamma >0$. This is accomplished by expressing the Zak transform…

Functional Analysis · Mathematics 2007-05-23 A. J. E. M. Janssen , Thomas Strohmer

We investigate the frame set of regular multivariate Gaussian Gabor frames using methods from K\"ahler geometry such as H\"ormander's $\dbar$-$L^2$ estimate with singular weight, Demailly's Calabi--Yau method for K\"ahler currents and a…

Complex Variables · Mathematics 2023-06-02 Franz Luef , Xu Wang

Collections of time- and frequency-shifts of suitably chosen generators (Alltop or random vectors) proved successful for many applications in sparse recovery and related fields. It was shown in \cite{xia2005achieving} that taking a…

Classical Analysis and ODEs · Mathematics 2016-01-20 Irena Bojarovska , Victoria Paternostro

We report on initial findings on Gabor systems with multivariate Gaussian window. Unlike the existing characterisation for dimension one in terms of lattice density, our results indicate that the behavior of Gaussians in higher-dimensional…

Functional Analysis · Mathematics 2010-08-24 G"otz E. Pfander , Peter Rashkov

We show how to cast an interacting system of M--branes into manifestly gauge-invariant form using an arrangement of higher-dimensional Dirac surfaces. Classical M--theory has a cohomologically nontrivial and noncommutative set of gauge…

High Energy Physics - Theory · Physics 2009-11-10 J. Kalkkinen , K. S. Stelle

Let $H$ be an infinite-dimensional Hilbert space. We prove that every unconditional Schauder frame for $H$ contains a subsequence that can be normalized to form a frame for $H$. As a consequence, every semi-normalized unconditional Schauder…

Classical Analysis and ODEs · Mathematics 2026-03-16 Pu-Ting Yu

We show that if the Gabor system $\{ g(x-t) e^{2\pi i s x}\}$, $t \in T$, $s \in S$, is an orthonormal basis in $L^2(\mathbb{R})$ and if the window function $g$ is compactly supported, then both the time shift set $T$ and the frequency…

Classical Analysis and ODEs · Mathematics 2025-01-10 Alberto Debernardi Pinos , Nir Lev

We study finite systems of vectors whose frame operator matrices are unitarily equivalent, via explicit and computationally efficient unitary transformations, to block-diagonal matrices. We call such systems block-equivalent. We show that a…

Functional Analysis · Mathematics 2026-05-18 Oleg Asipchuk , Laura De Carli , Luis Rodriguez

We consider Hamiltonian deformations of Gabor systems, where the window evolves according to the action of a Schr\"odinger propagator and the phase-space nodes evolve according to the corresponding Hamiltonian flow. We prove the stability…

Mathematical Physics · Physics 2016-11-29 Maurice A. de Gosson , Karlheinz Gröchenig , José Luis Romero

Using a variant of the Sobolev Embedding Theorem, we prove an uncertainty principle related to Gabor systems that generalizes the Balian-Low Theorem. Namely, if $f\in H^{p/2}(\R)$ and $\hat f\in H^{p'/2}(\R)$ with $1<p<\infty$,…

Classical Analysis and ODEs · Mathematics 2010-07-16 S. Zubin Gautam

Hilbert space fusion frames are a natural extension of Hilbert space frames, extending the notion from a set of vectors in a Hilbert space to a set of subspaces of a Hilbert space with analogous notions of overcompleteness and boundedness.…

Functional Analysis · Mathematics 2017-06-23 Mozhgan Mohammadpour , Brian Tuomanen , Rajab Ali Kamyabi Gol

Frame theory has been rapidly generalized and various generalizations have been developed. In this paper, we present a brief survey of the frames in Hilbert $C^{\ast}$-modules, including frames, $\ast$-frames, g-frames, $\ast$-g-frames,…

Functional Analysis · Mathematics 2022-12-20 M'hamed Ghiati , Mohammed Mouniane , Mohamed Rossafi

We obtain Gabor frame characterisations of modulation spaces defined via a class of translation-modulation invariant Banach spaces of distributions that was recently introduced in $[10]$. We show that these spaces admit an atomic…

Functional Analysis · Mathematics 2021-02-08 Andreas Debrouwere , Bojan Prangoski

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…

Functional Analysis · Mathematics 2024-05-21 Karlheinz Gröchenig

This work developes a quantitative framework for describing the overcompleteness of a large class of frames. A previous paper introduced notions of localization and approximation between two frames $\mathcal{F} = \{f_i\}_{i \in I}$ and…

Functional Analysis · Mathematics 2007-05-23 R. Balan , P. G. Casazza , C. Heil , Z. Landau

In this work we show that if the frame property of a Gabor frame with window in Feichtinger's algebra and a fixed lattice only depends on the parity of the window, then the lattice can be replaced by any other lattice of the same density…

Functional Analysis · Mathematics 2019-12-06 Markus Faulhuber

Gabor frames have interested many mathematicians and physicists due to their potential applications in time-frequency analysis, in particular, signal processing. A Gabor system is a collection of vectors which is obtained by applying…

Functional Analysis · Mathematics 2022-05-23 Lalit Kumar Vashisht , Hari Krishan Malhotra

In this paper a large class of universal windows for Gabor frames (Weyl-Heisenberg frames) is constructed. These windows have the fundamental property that every overcritical rectangular lattice generates a Gabor frame. Likewise, every…

Information Theory · Computer Science 2013-08-14 Severin Bannert , Karlheinz Gröchenig , Joachim Stöckler