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Related papers: Wavelets and sparsity for Faraday tomography

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Full-waveform inversion (FWI) is an effective method for imaging subsurface properties using sparsely recorded data. It involves solving a wave propagation problem to estimate model parameters that accurately reproduce the data. Recent…

Optimization and Control · Mathematics 2025-05-02 Ali Gholami

We address the problem of recovering a sparse signal observed by a resource constrained wireless sensor network under channel fading. Sparse random matrices are exploited to reduce the communication cost in forwarding information to a…

Information Theory · Computer Science 2015-04-16 Thakshila Wimalajeewa , Pramod K. Varshney

Cone-Beam Computed Tomography (CBCT) is essential in medical imaging, and the Feldkamp-Davis-Kress (FDK) algorithm is a popular choice for reconstruction due to its efficiency. However, FDK is susceptible to noise and artifacts. While…

Image and Video Processing · Electrical Eng. & Systems 2025-05-21 Yipeng Sun , Linda-Sophie Schneider , Chengze Ye , Mingxuan Gu , Siyuan Mei , Siming Bayer , Andreas Maier

Full Waveform Inversion (FWI) is a successful and well-established inverse method for reconstructing material models from measured wave signals. In the field of seismic exploration, FWI has proven particularly successful in the…

Computational Engineering, Finance, and Science · Computer Science 2023-12-05 Tim Bürchner , Philipp Kopp , Stefan Kollmannsberger , Ernst Rank

Next-generation spectro-polarimetric broadband surveys will probe cosmic magnetic fields in unprecedented detail, using the magneto-optical effect known as Faraday rotation. However, non-parametric methods such as RMCLEAN can introduce…

Instrumentation and Methods for Astrophysics · Physics 2021-12-08 Luke Pratley , Melanie Johnston-Hollitt , Bryan M. Gaensler

Recent progress in synthetic aperture sonar (SAS) technology and processing has led to significant advances in underwater imaging, outperforming previously common approaches in both accuracy and efficiency. There are, however, inherent…

Numerical Analysis · Mathematics 2017-06-28 John McKay , Anne Gelb , Vishal Monga , Raghu Raj

The paper presents algorithms to realize effectively and accurately the stepped-frequency waveform reflectometry (SFWR), i.e. the reflectometric technique based on the use of sinusoidal bursts. This technique is useful for monitoring the…

Signal Processing · Electrical Eng. & Systems 2020-02-19 Nicola Giaquinto , Marco Scarpetta , Maurizio Spadavecchia

Full waveform inversion (FWI) delivers high-resolution images of the subsurface by minimizing iteratively the misfit between the recorded and calculated seismic data. It has been attacked successfully with the Gauss-Newton method and…

Geophysics · Physics 2016-11-07 Lingchen Zhu , Entao Liu , James H. McClellan

Compressed sensing has empowered quality image reconstruction with fewer data samples than previously though possible. These techniques rely on a sparsifying linear transformation. The Daubechies wavelet transform is a common sparsifying…

Image and Video Processing · Electrical Eng. & Systems 2021-06-17 Nicholas Dwork , Daniel O'Connor , Corey A. Baron , Ethan M. I. Johnson , Adam B. Kerr , John M. Pauly , Peder E. Z. Larson

In many signal processing applications, one wishes to acquire images that are sparse in transform domains such as spatial finite differences or wavelets using frequency domain samples. For such applications, overwhelming empirical evidence…

Computer Vision and Pattern Recognition · Computer Science 2013-10-22 Felix Krahmer , Rachel Ward

An inverse nonequispaced fast Fourier transform (iNFFT) is a fast algorithm to compute the Fourier coefficients of a trigonometric polynomial from nonequispaced sampling data. However, various applications such as magnetic resonance imaging…

Numerical Analysis · Mathematics 2025-06-09 Melanie Kircheis , Daniel Potts

The Galactic Faraday depth sky is a tracer for both the Galactic magnetic field and the thermal electron distribution. It has been previously reconstructed from polarimetric measurements of extra-galactic point sources. Here, we improve on…

Astrophysics of Galaxies · Physics 2020-01-29 Sebastian Hutschenreuter , Torsten A. Enßlin

We investigate the properties of the Galactic ISM by applying Faraday tomography to a radio polarization data set in the direction of the Galactic anti-centre. We address the problem of missing large-scale structure in our data, and show…

Astrophysics · Physics 2015-05-13 D. H. F. M. Schnitzeler , P. Katgert , A. G. de Bruyn

There have been many efforts to correct systematic effects in astronomical light curves to improve the detection and characterization of planetary transits and astrophysical variability. Algorithms like the Trend Filtering Algorithm (TFA)…

Instrumentation and Methods for Astrophysics · Physics 2018-11-14 D. del Ser , O. Fors , J. Núñez

This paper is dedicated to design a direct sampling method of inverse electromagnetic scattering problems, which uses multi-frequency sparse backscattering far field data for reconstructing the boundary of perfectly conducting obstacles. We…

Analysis of PDEs · Mathematics 2020-10-28 Tilo Arens , Xia Ji , Xiaodong Liu

Advances in radio spectro-polarimetry offer the possibility to disentangle complex regions where relativistic and thermal plasmas mix in the interstellar and intergalactic media. Recent work has shown that apparently simple Faraday Rotation…

Instrumentation and Methods for Astrophysics · Physics 2018-11-07 Shea Brown , Brandon Bergerud , Allison Costa , B. M. Gaensler , Jacob Isbell , Daniel LaRocca , Ray Norris , Cormac Purcell , Lawrence Rudnick , Xiaohui Sun

In this paper we present a detailed analysis of the Faraday depth (FD) spectrum and its clean components obtained through the application of the commonly used technique of Faraday rotation measure synthesis to analyze spectro-polarimetric…

Astrophysics of Galaxies · Physics 2019-11-21 Aritra Basu , Andrew Fletcher , S. A. Mao , Blakesley Burkhart , Rainer Beck , Dominic Schnitzeler

Bayesian image restoration has had a long history of successful application but one of the limitations that has prevented more widespread use is that the methods are generally computationally intensive. The authors recently addressed this…

Methodology · Statistics 2023-06-02 Karl Young , John Kornak , Eric Friedman

This paper is concerned with the inverse obstacle scattering problem with phaseless far-field data at a fixed frequency. The main difficulty of this problem is the so-called translation invariance property of the modulus of the far-field…

Numerical Analysis · Mathematics 2018-08-29 Bo Zhang , Haiwen Zhang

Dedicated 'Stage IV' observatories will soon observe the entire extragalactic sky, to measure the 'cosmic shear' distortion of galaxy shapes by weak gravitational lensing. To measure the apparent shapes of those galaxies, we present an…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-08 Xiangchong Li , Yin Li , Richard Massey