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Related papers: Time-Frequency Analysis in the Unit Ball

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In this paper we address the problem of constructing a feature extractor which combines Mallat's scattering transform framework with time-frequency (Gabor) representations. To do this, we introduce a class of frames, called uniform covering…

Functional Analysis · Mathematics 2018-02-09 Wojciech Czaja , Weilin Li

The famous Fourier theorem states that, under some restrictions, any periodic function (or real world signal) can be obtained as a sum of sinusoids, and hence, a technique exists for decomposing a signal into its sinusoidal components. From…

Numerical Analysis · Computer Science 2008-04-24 Sossio Vergara

We construct frames adapted to a given cover of the time-frequency or time-scale plane. The main feature is that we allow for quite general and possibly irregular covers. The frame members are obtained by maximizing their concentration in…

Functional Analysis · Mathematics 2015-04-27 Monika Dörfler , José Luis Romero

We study the fractal uncertainty principle in the joint time-frequency representation, and we prove a version for the Short-Time Fourier transform with Gaussian window on the modulation spaces. This can equivalently be formulated in terms…

Functional Analysis · Mathematics 2022-04-08 Helge Knutsen

This study puts forward a generalization of the short-time Fourier-based Synchrosqueezing Transform using a new local estimate of instantaneous frequency. Such a technique enables not only to achieve a highly concentrated time-frequency…

Signal Processing · Electrical Eng. & Systems 2020-04-21 Duong-Hung Pham , Sylvain Meignen

In the coherent electron cooling, the modern hadron beam cooling technique, each hadron receives an individual kick from the electric field of the amplified electron density perturbation created in the modulator by this hadron in a…

Accelerator Physics · Physics 2015-06-17 Andrey Elizarov , Vladimir Litvinenko

$\newcommand{mc}[1]{\mathcal{#1}}$ $\newcommand{D}{\mc{D}(\mc{Q},L^p,\ell_w^q)}$ We present a framework for the construction of structured, possibly compactly supported Banach frames and atomic decompositions for decomposition spaces. Such…

Functional Analysis · Mathematics 2016-12-30 Felix Voigtlaender

We develop a representation of reverse-time migration in terms of Fourier integral operators the canonical relations of which are graphs. Through the dyadic parabolic decomposition of phase space, we obtain the solution of the wave equation…

Numerical Analysis · Mathematics 2015-09-24 Fredrik Andersson , Maarten V. de Hoop , Herwig Wendt

Universal multiport interferometers (UMIs) have emerged as a key tool for performing arbitrary linear transformations on optical modes, enabling precise control over the state of light in essential applications of classical and quantum…

Optics · Physics 2025-12-23 Vincent Girouard , Nicolás Quesada

This paper is concerned with frame decompositions of $\alpha$-modulation spaces. These spaces can be obtained as coorbit spaces for square-integrable representations of the affine Weyl-Heisenberg group modulo suitable subgroups. The theory…

Functional Analysis · Mathematics 2014-08-22 Peter Balazs , Dominik Bayer , Michael Speckbacher

We apply De Haro's Geometric View of Theories to one of the simplest quantum systems: a spinless particle on a line and on a circle. The classical phase space M = T*Q is taken as the base of a trivial Hilbert bundle E ~ M x H, and the…

Quantum Physics · Physics 2026-02-09 Eren Volkan Küçük

Let G be a locally analytic group. We use deformation theory and Emerton's 'augmented' Iwasawa modules to study the possible liftings of a given absolutely irreducible smooth modular representation of G to a unitary Banach space…

Representation Theory · Mathematics 2012-10-16 Tobias Schmidt

We investigate the structure of the commutative Banach algebra formed as the direct sum of integrable radial functions on the disc and the radial operators on the Bergman space, endowed with the convolution from quantum harmonic analysis as…

Functional Analysis · Mathematics 2026-01-01 Vishwa Dewage , Robert Fulsche , Gestur Ólafsson

We study quantum harmonic analysis (QHA) on the Bergman space $\mathcal{A}^2(\mathbb{B}^n)$ over the unit ball in $\mathbb{C}^n$. We formulate a Wiener's Tauberian theorem, and characterizations of the radial Toeplitz algebra over…

Functional Analysis · Mathematics 2025-03-20 Matthew Dawson , Vishwa Dewage , Mishko Mitkovski , Gestur Olafsson

Discrete transforms such as the discrete Fourier transform (DFT) or the discrete Hartley transform (DHT) furnish an indispensable tool in signal processing. The successful application of transform techniques relies on the existence of the…

Data Structures and Algorithms · Computer Science 2015-08-27 H. M. de Oliveira , R. J. Cintra , R. M. Campello de Souza

The fractional Fourier transform (FrFT), a fundamental operation in physics that corresponds to a rotation of phase space by any angle, is also an indispensable tool employed in digital signal processing for noise reduction. Processing of…

We use a right unitary decomposition to study an ultracold two-level atom interacting with a quantum field. We show that such a right unitary approach simplifies the numerical evolution for arbitrary position-dependent atom-field couplings.…

Quantum Physics · Physics 2015-06-02 F. Soto-Eguibar , A. Zúñiga-Segundo , B. M. Rodríguez-Lara , H. M. Moya-Cessa

We analyse the Gaussian wave packet transform. Based on the Fourier inversion formula and a partition of unity, which is formed by a collection of Gaussian basis functions, a new representation of square-integrable functions is presented.…

Numerical Analysis · Mathematics 2023-06-14 Paul Bergold , Caroline Lasser

We use time-frequency methods for the study of Fourier Integral operators (FIOs). In this paper we shall show that Gabor frames provide very efficient representations for a large class of FIOs. Indeed, similarly to the case of shearlets and…

Analysis of PDEs · Mathematics 2016-06-28 Elena Cordero , Fabio Nicola , Luigi Rodino

When passing through an undulator in a Free Electron Laser, dense bunches of relativistic electrons split into micro-bunches, attaining a periodic space-time structure. We show that the field of such periodically modulated bunches is…

Atomic Physics · Physics 2026-04-01 A. B. Voitkiv , E. Schneidmiller , T. Pfeifer