English
Related papers

Related papers: Slepian Scale-Discretised Wavelets on the Sphere

200 papers

We propose a transform for signals defined on the sphere that reveals their localized directional content in the spatio-spectral domain when used in conjunction with an asymmetric window function. We call this transform the directional…

Information Theory · Computer Science 2013-04-23 Z. Khalid , R. A. Kennedy , S. Durrani , P. Sadeghi , Y. Wiaux , J. D. McEwen

This study introduces a new multi-antenna array synthesizer based on Slepian functions. The synthesizer concentrates beamforming (BF) gain within a spatial region (i.e., an angular sector), optimizing Shannon capacity of the targeted…

Signal Processing · Electrical Eng. & Systems 2024-01-19 Hesham Sharkas

Recently, with the progress of science and the characteristic properties that distinguish the Slepian system called Prolate spheroidal wave functions from the others orthonormal systems, it became clear its important contributions in…

Functional Analysis · Mathematics 2022-06-10 Boulsane Mourad

In recent years, a rapidly growing literature has focussed on the construction of wavelet systems to analyze functions defined on the sphere. Our purpose in this paper is to generalize these constructions to situations where sections of…

Classical Analysis and ODEs · Mathematics 2010-06-22 Daryl Geller , Domenico Marinucci

Spherical CNNs generalize CNNs to functions on the sphere, by using spherical convolutions as the main linear operation. The most accurate and efficient way to compute spherical convolutions is in the spectral domain (via the convolution…

Machine Learning · Computer Science 2023-06-09 Carlos Esteves , Jean-Jacques Slotine , Ameesh Makadia

Blind deconvolution is the problem of recovering a convolutional kernel $\boldsymbol a_0$ and an activation signal $\boldsymbol x_0$ from their convolution $\boldsymbol y = \boldsymbol a_0 \circledast \boldsymbol x_0$. This problem is…

Computer Vision and Pattern Recognition · Computer Science 2019-01-08 Yuqian Zhang , Yenson Lau , Han-Wen Kuo , Sky Cheung , Abhay Pasupathy , John Wright

Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D Spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 F. Lanusse , A. Rassat , J. -L. Starck

This paper presents recent results obtained by the authors (partly in collaboration with A. Dabrowska) concerning expansions of zonal functions on Euclidean spheres into spherical harmonics and some applications of such expansions for…

Mathematical Physics · Physics 2008-04-24 Agata Bezubik , Aleksander Strasburger

A new construction of a directional continuous wavelet analysis on the sphere is derived herein. We adopt the harmonic scaling idea for the spherical dilation operator recently proposed by Sanz et al. but extend the analysis to a more…

Astrophysics · Physics 2011-10-28 J. D. McEwen , M. P. Hobson , A. N. Lasenby

In the present paper, multiscale systems of polynomial wavelets on an n-dimensional sphere are constructed. Scaling functions and wavelets are investigated,and their reproducing and localization properties and positive definiteness are…

Classical Analysis and ODEs · Mathematics 2018-04-10 Ilona Iglewska-Nowak

In the last few decades a series of increasingly sophisticated satellite missions has brought us gravity and magnetometry data of ever improving quality. To make optimal use of this rich source of information on the structure of Earth and…

Geophysics · Physics 2013-06-28 Alain Plattner , Frederik J. Simons

We adress the problem of spherical deconvolution in a non parametric statistical framework, where both the signal and the operator kernel are subject to error measurements. After a preliminary treatment of the kernel, we apply a…

Statistics Theory · Mathematics 2013-01-16 Thomas Vareschi

We investigate invariant random fields on the sphere using a new type of spherical wavelets, called needlets. These are compactly supported in frequency and enjoy excellent localization properties in real space, with quasi-exponentially…

Statistics Theory · Mathematics 2009-09-29 P. Baldi , G. Kerkyacharian , D. Marinucci , D. Picard

We develop techniques to solve ill-posed inverse problems on the sphere by sparse regularisation, exploiting sparsity in both axisymmetric and directional scale-discretised wavelet space. Denoising, inpainting, and deconvolution problems,…

Information Theory · Computer Science 2017-08-17 Christopher G. R. Wallis , Yves Wiaux , Jason D. McEwen

A new technique is presented for producing images from interferometric data. The method, ``smear fitting'', makes the constraints necessary for interferometric imaging double as a model, with uncertainties, of the sky brightness…

Astrophysics · Physics 2009-11-11 Robert I. Reid

In the context of functional data analysis, probability density functions as non-negative functions are characterized by specific properties of scale invariance and relative scale which enable to represent them with the unit integral…

Numerical Analysis · Mathematics 2019-12-19 Jitka Machalova , Renata Talska , Karel Hron , Ales Gaba

Spectral embedding uses eigenfunctions of the discrete Laplacian on a weighted graph to obtain coordinates for an embedding of an abstract data set into Euclidean space. We propose a new pre-processing step of first using the eigenfunctions…

Machine Learning · Statistics 2016-07-18 Alexander Cloninger , Stefan Steinerberger

In a previous paper we have introduced a new class of radial basis functions that are powerful means to approximate functions by quasi-interpolation. In this article we extend the results to create new ways of approximating functions by…

Numerical Analysis · Mathematics 2025-12-18 M. Buhmann , J. Jódar , M. Rodríguez

Subspaces obtained by the orthogonal projection of locally supported square-integrable vector fields onto the Hardy spaces $H_+(\mathbb{S})$ and $H_-(\mathbb{S})$, respectively, play a role in various inverse potential field problems since…

Numerical Analysis · Mathematics 2023-07-06 Christian Gerhards , Xinpeng Huang

We propose a novel basis of vector functions, the mixed vector spherical harmonics that are closely related to the functions $F_{lm}$ of Sheppard and T\"or\"ok and help us reduce the concentration problem of tangential vector fields within…

Classical Analysis and ODEs · Mathematics 2013-08-20 Kornél Jahn , Nándor Bokor