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Related papers: PURIFYing real radio interferometric observations

200 papers

The spatial-frequency coverage of a radio interferometer is increased by combining samples acquired at different times and observing frequencies. However, astrophysical sources often contain complicated spatial structure that varies within…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 U. Rau

Interferometers play an increasingly important role for spatially resolved observations. If employed at full potential, interferometry can probe an enormous dynamic range in spatial scale. Interpretation of the observed visibilities…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 C. Brinch , C. P. Dullemond

This manual is intended to help ALMA and other interferometer users improve images by recognising limitations and how to overcome them and deciding when and how to use self-calibration. The images provided by the ALMA Science Archive are…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 A. M. S. Richards , E. Moravec , S. Etoka , E. B. Fomalont , A. F. Pérez-Sánchez , M. C. Toribio , R. A. Laing

We propose a method that combines sparse depth (LiDAR) measurements with an intensity image and to produce a dense high-resolution depth image. As there are few, but accurate, depth measurements from the scene, our method infers the…

Image and Video Processing · Electrical Eng. & Systems 2019-11-01 Alireza Ahrabian , Joao F. C. Mota , Andrew M. Wallace

The new generation radio telescopes, such as the Square Kilometre Array (SKA), are expected to reach sufficient sensitivity and resolution to provide large number densities of resolved faint sources, and therefore to open weak gravitational…

Instrumentation and Methods for Astrophysics · Physics 2022-04-12 Marzia Rivi , Lance Miller

The iterative refinement method (IRM) has been very successfully applied in many different fields for examples the modern quantum chemical calculation and CT image reconstruction. It is proved that the refinement method can create an exact…

Medical Physics · Physics 2015-12-23 Kang Yang , Kevin Yang , Xintie Yang , Shuang-Ren Zhao

Spatial frequency estimation from a mixture of noisy sinusoids finds applications in various fields. While subspace-based methods offer cost-effective super-resolution parameter estimation, they demand precise array calibration, posing…

Signal Processing · Electrical Eng. & Systems 2024-10-23 Tianyi Liu , Sai Pavan Deram , Khaled Ardah , Martin Haardt , Marc E. Pfetsch , Marius Pesavento

Recently, the progress of learning-by-synthesis has proposed a training model for synthetic images, which can effectively reduce the cost of human and material resources. However, due to the different distribution of synthetic images…

Computer Vision and Pattern Recognition · Computer Science 2020-02-17 Yuxiao Yan , Yang Yan , Jinjia Peng , Huibing Wang , Xianping Fu

Image quality in mosaicked observations from interferometric radio telescopes is strongly dependent on the accuracy with which the antenna primary beam is calibrated. The next generation of radio telescope arrays such as the Allen Telescope…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 Charles L. H. Hull , Geoffrey C. Bower , Steve Croft , Peter K. G. Williams , Casey Law , David Whysong

The Square Kilometre Array (SKA) is the largest radio interferometer under construction in the world. Its immense amount of visibility data poses a considerable challenge to the subsequent processing by the science data processor (SDP).…

Instrumentation and Methods for Astrophysics · Physics 2022-03-30 Qing-Wen Deng , Feng Wang , Hui Deng , Ying Mei , Jing Li , Oleg Smirnov , Shao-Guang Guo

The volume of radio-astronomical data is a considerable burden in the processing and storing of radio observations with high time and frequency resolutions and large bandwidths. Lossy compression of interferometric radio-astronomical data…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 A. R. Offringa

In this work, we propose using camera arrays coupled with coherent illumination as an effective method of improving spatial resolution in long distance images by a factor of ten and beyond. Recent advances in ptychography have demonstrated…

Computer Vision and Pattern Recognition · Computer Science 2015-11-29 Jason Holloway , M. Salman Asif , Manoj Kumar Sharma , Nathan Matsuda , Roarke Horstmeyer , Oliver Cossairt , Ashok Veeraraghavan

When completed the Square Kilometre Array (SKA) will feature an unprecedented rate of image generation. While previous generations of telescopes have relied on human expertise to extract scientifically interesting information from the…

Instrumentation and Methods for Astrophysics · Physics 2016-01-19 C. Hollitt , M. Johnston-Hollitt , S. Dehghan , M. Frean , T. Bulter-Yeoman

In order to meet its cutting-edge scientific objectives, the Square Kilometre Array (SKA) telescope requires high-precision frequency references to be distributed to each of its antennas. The frequency references are distributed via…

Instrumentation and Methods for Astrophysics · Physics 2017-06-20 David Gozzard , Sascha Schediwy , Richard Dodson , Maria Rioja , Mike Hill , Brett Lennon , Jock McFee , Peter Mirtschin , Jamie Stevens , Keith Grainge

Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

Stellar amplitude interferometry is limited by the need to have optical distances fixed and known to a fraction of the wavelength. We suggest reviving intensity interferometry, which requires hardware which is many orders of magnitude less…

Astrophysics · Physics 2009-11-11 Aviv Ofir , Erez N. Ribak

Research in ultrasound imaging is limited in reproducibility by two factors: First, many existing ultrasound pipelines are protected by intellectual property, rendering exchange of code difficult. Second, most pipelines are implemented in…

Computer Vision and Pattern Recognition · Computer Science 2018-05-11 Rüdiger Göbl , Nassir Navab , Christoph Hennersperger

We leverage the Sparsity Averaging Reweighted Analysis (SARA) approach for interferometric imaging, that is based on convex optimisation, for the super-resolution of Cyg A from observations at the frequencies 8.422GHz and 6.678GHz with the…

Instrumentation and Methods for Astrophysics · Physics 2018-05-15 Arwa Dabbech , Alexandru Onose , Abdullah Abdulaziz , Richard A. Perley , Oleg M. Smirnov , Yves Wiaux

Future observations of 21 cm emission from neutral hydrogen survey will become a promising approach to probe the large scale structure of Universe. In this paper, we investigate the impacts of Square Kilometer Array (SKA) 21 cm observation…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-12 Jing-Fei Zhang , Li-Yang Gao , Dong-Ze He , Xin Zhang

Backed by advances in digital electronics, signal processing, computation, and storage technologies, aperture arrays, which had strongly influenced the design of telescopes in the early years of radio astronomy, have made a comeback. Amid…