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Related papers: Time-Frequency Analysis in the Unit Ball

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Recently representation theory has been used to provide atomic decompositions for a large collection of classical Banach spaces. In this paper we extend the techniques to also include projective representations. As our main application we…

Functional Analysis · Mathematics 2019-03-28 Jens Gerlach Christensen , Amer H. Darweesh , Gestur Olafsson

We present a novel family of continuous, linear time-frequency transforms adaptable to a multitude of (nonlinear) frequency scales. Similar to classical time-frequency or time-scale representations, the representation coefficients are…

Functional Analysis · Mathematics 2024-03-20 Nicki Holighaus , Christoph Wiesmeyr , Peter Balazs

The $\alpha$-modulation transform is a time-frequency transform generated by square-integrable representations of the affine Weyl-Heisenberg group modulo suitable subgroups. In this paper we prove new conditions that guarantee the…

Functional Analysis · Mathematics 2016-03-02 Michael Speckbacher , Dominik Bayer , Stephan Dahlke , Peter Balazs

Based on Beurling's theory of balayage, we develop the theory of non-uniform sampling in the context of the theory of frames for the settings of the Short Time Fourier Transform and pseudo-differential operators. There is sufficient…

Functional Analysis · Mathematics 2013-10-10 Enrico Au-Yeung , John J. Benedetto

We derive atomic decompositions and frames for weighted Bergman spaces of several complex variables on the unit ball in the spirit of Coifman, Rochberg, and Luecking. In contrast to our predecessors, we use group theoretic methods, in…

Complex Variables · Mathematics 2015-04-03 Jens Christensen , Karlheinz Gröchenig , Gestur Ólafsson

We define ultradistributional wave front sets with respect to translation-modulation invariant Banach spaces of ultradistributions having solid Fourier image. The main result is their characterisation by the short-time Fourier transform.

Analysis of PDEs · Mathematics 2018-09-25 Pavel Dimovski , Bojan Prangoski

The quantum mechanical harmonic oscillator Hamiltonian generates a one-parameter unitary group W(\theta) in L^2(R) which rotates the time-frequency plane. In particular, W(\pi/2) is the Fourier transform. When W(\theta) is applied to any…

Mathematical Physics · Physics 2009-11-07 Gerald Kaiser

Phase-space analysis or time-frequency analysis can be thought as Fourier analysis simultaneously both in time and in frequency, originating from signal processing and quantum mechanics. On groups having unitary Fourier transform, we…

Functional Analysis · Mathematics 2020-09-21 Ville Turunen

Unitary Fourier transform lies at the core of the multitudinous computational and metrological algorithms. Here we show experimentally how the unitary Fourier transform-based phase estimation protocol, used namely in quantum metrology, can…

The Funk-Radon transform assigns to a function defined on the unit sphere its integrals along all great circles of the sphere. In this paper, we consider a frame decomposition of the Funk-Radon transform, which is a flexible alternative to…

Numerical Analysis · Mathematics 2023-05-16 Michael Quellmalz , Lukas Weissinger , Simon Hubmer , Paul D. Erchinger

Starting with an integrable unitary representation of a locally compact group and its associated voice transform, coorbit theory describes the construction and investigation of the so-called coorbit spaces. A coorbit space consists of…

Functional Analysis · Mathematics 2024-01-24 Jan Zimmermann

Integral transforms arising from the separable solutions to the Helmholtz differential equation are presented. Pairs of these integral transforms are related via Plancherel theorem and, ultimately, any of these integral transforms may be…

Analysis of PDEs · Mathematics 2016-08-14 B. M. Rodríguez-Lara

Fourier transforms are ubiquitous mathematical tools in basic and applied sciences. We here report classical and quantum optical realizations of the discrete fractional Fourier transform, a generalization of the Fourier transform. In the…

We study Fourier theory on quantum Euclidean space. A modified version of the general definition of the Fourier transform on a quantum space is used and its inverse is constructed. The Fourier transforms can be defined by their Bochner's…

Mathematical Physics · Physics 2011-08-08 Kevin Coulembier

The time-frequency content of a signal can be measured by the Gabor transform or windowed Fourier transform. This is a function defined on phase space that is computed by taking the Fourier transform of the product of the signal against a…

funct-an · Mathematics 2008-02-03 Jayakumar Ramanathan , Pankaj Topiwala

Windowing a Fourier transform is a useful tool, which gives us the similarity between the signal and time frequency signal, and it allows to get sense when/where ceratin frequencies occur in the input signal, this method is introduced by…

Classical Analysis and ODEs · Mathematics 2019-01-07 Mohammed El Kassimi , Mustapha Boujeddaine , Said Fahlaoui

The methods of mode decomposition and Fourier analysis of classical and quantum fields on curved spacetimes previously available mainly for the scalar field on Friedman- Robertson-Walker (FRW) spacetimes are extended to arbitrary vector…

Mathematical Physics · Physics 2016-11-29 Zhirayr G. Avetisyan

This paper ist concerned with recent progress in the context of coorbit space theory. Based on a square integrable group representation, the coorbit theory provides new families of associated smoothness spaces, where the smoothness of a…

This paper is concerned with the characterization of $\alpha$-modulation spaces by Banach frames, i.e., stable and redundant non-orthogonal expansions, constituted of functions obtained by a suitable combination of translation, modulation…

Functional Analysis · Mathematics 2007-05-23 Massimo Fornasier

Many stochastic processes are defined on special geometrical objects like spheres and cones. We describe how tools from harmonic analysis, i.e. Fourier analysis on groups, can be used to investigate probability density functions (pdfs) on…

Computer Vision and Pattern Recognition · Computer Science 2016-12-15 Reiner Lenz
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