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Related papers: Faraday Tomography with Sparse Modeling

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Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

Rotating Synthetic Aperture Radar (ROSAR) can generate a 360$^\circ$ image of its surrounding environment using the collected data from a single moving track. Due to its non-linear track, the Back-Projection Algorithm (BPA) is commonly used…

Signal Processing · Electrical Eng. & Systems 2023-09-18 Wei Zhao , Cai Wen , Quan Yuan , Rong Zheng

We propose a new superresolution imaging technique for interferometry using sparse modeling, utilizing two regularization terms: the $\ell_1$-norm and a new function named Total Squared Variation (TSV) of the brightness distribution. TSV is…

Instrumentation and Methods for Astrophysics · Physics 2018-06-06 Kazuki Kuramochi , Kazunori Akiyama , Shiro Ikeda , Fumie Tazaki , Vincent L. Fish , Hung-Yi Pu , Keiichi Asada , Mareki Honma

Sparse modeling is one of the efficient techniques for imaging that allows recovering lost information. In this paper, we present a novel iterative phase-retrieval algorithm using a sparse representation of the object amplitude and phase.…

Computer Vision and Pattern Recognition · Computer Science 2011-08-17 Artem Migukin , Vladimir Katkovnik , Jaakko Astola

Compressed sensing is an imaging paradigm that allows one to invert an underdetermined linear system by imposing the a priori knowledge that the sought after solution is sparse (i.e., mostly zeros). Previous works have shown that if one…

Image and Video Processing · Electrical Eng. & Systems 2023-12-05 Nicholas Dwork , Erin K. Englund

Accurate estimates of the horizontal electric field on the Sun's visible surface are important not only for estimating the Poynting flux of magnetic energy into the corona but also for driving time-dependent magnetohydrodynamic models of…

Solar and Stellar Astrophysics · Physics 2017-02-22 A. R. Yeates

Measurements of the polarization of radio emission are subject to a number of depolarization effects such as bandwidth depolarization, which is caused by the averaging effect of a finite channel bandwidth combined with the…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Maxwell A. Fine , Cameron L. Van Eck , Luke Pratley

We investigate whether the method of wavelet-based Faraday rotation measure (RM) Synthesis can help us to identify structures of regular and turbulent magnetic fields in extended magnetized objects, such as galaxies and galaxy clusters.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 R. Beck , P. Frick , R. Stepanov , D. Sokoloff

In many applications it is important to estimate a fluid flow field from limited and possibly corrupt measurements. Current methods in flow estimation often use least squares regression to reconstruct the flow field, finding the…

Fluid Dynamics · Physics 2019-11-06 Jared Callaham , Kazuki Maeda , Steven L. Brunton

We propose a variational regularisation approach for the problem of template-based image reconstruction from indirect, noisy measurements as given, for instance, in X-ray computed tomography. An image is reconstructed from such measurements…

Optimization and Control · Mathematics 2019-04-02 Lukas F. Lang , Sebastian Neumayer , Ozan Öktem , Carola-Bibiane Schönlieb

The emerging generation of radio interferometric (RI) telescopes, such as the Square Kilometre Array (SKA), will acquire massive volumes of data and transition radio astronomy to a big-data era. The ill-posed inverse problem of imaging the…

Instrumentation and Methods for Astrophysics · Physics 2019-04-04 Xiaohao Cai , Luke Pratley , Jason D. McEwen

(abridged) We run a Faraday structure determination data challenge to benchmark the currently available algorithms including Faraday synthesis (previously called RM synthesis in the literature), wavelet, compressive sampling and…

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

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

The incomplete sampling of data in complex polarization measurements from radio telescopes negatively affects both the rotation measure (RM) transfer function and the Faraday depth spectra derived from these data. Such gaps in polarization…

Instrumentation and Methods for Astrophysics · Physics 2021-02-24 S. W. Ndiritu , A. M. M. Scaife , D. L. Tabb , M. Carcamo , J. Hanson

The sparse-driven radar imaging can obtain the high-resolution images about target scene with the down-sampled data. However, the huge computational complexity of the classical sparse recovery method for the particular situation seriously…

Quantum Physics · Physics 2022-01-05 Xiaowen Liu , Chen Dong , Ying Luo , Le Kang , Yong Liu , Qun Zhang

Wide-band radio polarization observations offer the possibility to recover information about the magnetic fields in synchrotron sources, such as details of their three-dimensional configuration, that has previously been inaccessible. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Cathy Horellou , Andrew Fletcher

Next generation radio interferometric telescopes are entering an era of big data with extremely large data sets. While these telescopes can observe the sky in higher sensitivity and resolution than before, computational challenges in image…

Instrumentation and Methods for Astrophysics · Physics 2019-12-17 Luke Pratley , Jason D. McEwen , Mayeul d'Avezac , Xiaohao Cai , David Perez-Suarez , Ilektra Christidi , Roland Guichard

The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the…

Astrophysics · Physics 2014-11-18 Chen Ben-David , Amir Leshem

Statistics of polarized synchrotron radiation carry information about the properties of the underlying turbulence. Different statistical measures constructed from observables probe turbulence properties in different ways. We consider a…

Astrophysics of Galaxies · Physics 2026-02-26 Aliaksandr Melnichenka , Alex Lazarian , Dmitri Pogosyan