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Related papers: LOFAR Sparse Image Reconstruction

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The sparse-views x-ray computed tomography (CT) is essential for medical diagnosis and industrial nondestructive testing. However, in particular, the reconstructed image usually suffers from complex artifacts and noise, when the sampling is…

Medical Physics · Physics 2019-10-08 Genwei Ma , Yining Zhu , Xing Zhao

The Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) is a low-frequency radio continuum survey of the Northern sky at an unparalleled resolution and sensitivity. In order to fully exploit this huge dataset and those produced by the…

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

Shortwave-infrared(SWIR) spectral information, ranging from 1 {\mu}m to 2.5{\mu}m, overcomes the limitations of traditional color cameras in acquiring scene information. However, conventional SWIR hyperspectral imaging systems face…

Computer Vision and Pattern Recognition · Computer Science 2024-07-25 Linqiang Li , Jinglei Hao , Yongqiang Zhao , Pan Liu , Haofang Yan , Ziqin Zhang , Seong G. Kong

Radiation symmetry evaluation is critical to the laser driven Inertial Confinement Fusion (ICF), which is usually done by solving a view-factor equation model. The model is nonlinear, and the number of equations can be very large when the…

Signal Processing · Electrical Eng. & Systems 2019-08-20 Yanfeng Zhang

Sparse arrays have been widely exploited in radar systems because of their advantages in achieving large array aperture at low hardware cost, while significantly reducing mutual coupling. However, sparse arrays suffer from high sidelobes…

Signal Processing · Electrical Eng. & Systems 2025-03-10 Ruxin Zheng , Shunqiao Sun , Hongshan Liu

The International LOFAR Telescope (ILT) is a pan-European radio interferometer with baselines up to 2,000 km. This provides sub-arcsecond resolution at frequencies of <200 MHz. Since starting science operations in 2012, the ILT has carried…

Next-generation radio interferometers, such as the Square Kilometre Array (SKA), will revolutionise our understanding of the universe through their unprecedented sensitivity and resolution. However, standard methods in radio interferometry…

Instrumentation and Methods for Astrophysics · Physics 2017-02-23 Luke Pratley , Jason D. McEwen , Mayeul d'Avezac , Rafael E. Carrillo , Alexandru Onose , Yves Wiaux

The LOw Frequency ARray (LOFAR) is a next-generation radio telescope which uses thousands of stationary dipoles to observe celestial phenomena. These dipoles are grouped in various 'stations' which are centred on the Netherlands with…

Solar and Stellar Astrophysics · Physics 2019-08-13 Richard A. Fallows , Ashish Asgekar , Mario M Bisi , Andrew R. Breen , Sander ter Veen

In recent years, computational Time-of-Flight (ToF) imaging has emerged as an exciting and a novel imaging modality that offers new and powerful interpretations of natural scenes, with applications extending to 3D, light-in-flight, and…

Image and Video Processing · Electrical Eng. & Systems 2024-11-05 Ruiming Guo , Ayush Bhandari

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

In portable, 3-D, or ultra-fast ultrasound (US) imaging systems, there is an increasing demand to reconstruct high quality images from limited number of data. However, the existing solutions require either hardware changes or…

Computer Vision and Pattern Recognition · Computer Science 2017-10-31 Yeo Hun Yoon , Jong Chul Ye

We introduce a novel optimization algorithm for image recovery under learned sparse and low-rank constraints, which we parameterize as weighted extensions of the $\ell_p^p$-vector and $\mathcal S_p^p$ Schatten-matrix quasi-norms for…

Computer Vision and Pattern Recognition · Computer Science 2023-04-21 Stamatios Lefkimmiatis , Iaroslav Koshelev

Reconstructing continuous signals from a small number of discrete samples is a fundamental problem across science and engineering. In practice, we are often interested in signals with 'simple' Fourier structure, such as bandlimited,…

Data Structures and Algorithms · Computer Science 2018-12-24 Haim Avron , Michael Kapralov , Cameron Musco , Christopher Musco , Ameya Velingker , Amir Zandieh

Observations of the EoR with the 21-cm hyperfine emission of neutral hydrogen (HI) promise to open an entirely new window onto the formation of the first stars, galaxies and accreting black holes. In order to characterize the weak 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Abhik Ghosh , L. V. E. Koopmans , Emma Chapman , Vibor Jelic

Light field photography enables to record 4D images, containing angular information alongside spatial information of the scene. One of the important applications of light field imaging is post-capture refocusing. Current methods require for…

Computer Vision and Pattern Recognition · Computer Science 2020-09-08 Shachar Ben Dayan , David Mendlovic , Raja Giryes

We investigate the reconstruction problem of limited angle tomography. Such problems arise naturally in applications like digital breast tomosynthesis, dental tomography, electron microscopy etc. Since the acquired tomographic data is…

Numerical Analysis · Mathematics 2011-09-05 Jürgen Frikel

In order to measure the radial displacements of facets on surface of a growing spherical Cu_{2-\delta}Se crystal with sub-nanometer resolution, we have investigated the reliability and accuracy of standard method of Fourier analysis of…

Optics · Physics 2009-11-13 Jadranko Gladic , Zlatko Vucic , Davorin Lovric

Interferometric phase (InPhase) imaging is an important part of many present-day coherent imaging technologies. Often in such imaging techniques, the acquired images, known as interferograms, suffer from two major degradations: 1) phase…

Signal Processing · Electrical Eng. & Systems 2019-11-25 Joshin P. Krishnan , Mário A. T. Figueiredo , José M. Bioucas-Dias

We consider the problem of recovering signals from their power spectral density. This is a classical problem referred to in literature as the phase retrieval problem, and is of paramount importance in many fields of applied sciences. In…

Information Theory · Computer Science 2013-11-12 Kishore Jaganathan , Samet Oymak , Babak Hassibi