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In radio astronomy, visibility data, which are measurements of wave signals from radio telescopes, are transformed into images for observation of distant celestial objects. However, these resultant images usually contain both real sources…

Instrumentation and Methods for Astrophysics · Physics 2023-11-29 Ruoqi Wang , Zhuoyang Chen , Jiayi Zhu , Qiong Luo , Feng Wang

This paper investigates universal polar coding schemes. In particular, a notion of ordering (called convolutional path) is introduced between probability distributions to determine when a polar compression (or communication) scheme designed…

Information Theory · Computer Science 2010-12-03 Emmanuel Abbe

Upcoming radio interferometers are aiming to image the sky at new levels of resolution and sensitivity, with wide-band image cubes reaching close to the Petabyte scale for SKA. Modern proximal optimization algorithms have shown a potential…

Instrumentation and Methods for Astrophysics · Physics 2023-08-22 Pierre-Antoine Thouvenin , Abdullah Abdulaziz , Arwa Dabbech , Audrey Repetti , Yves Wiaux

This study is concerned with the design of a Mueller imaging polarimeter for the visualization of spatially-varying Mueller matrix fields. A simplified calibration procedure is advocated, where all the optical elements are calibrated…

Instrumentation and Detectors · Physics 2018-11-08 Yvain Quéau , Florian Leporcq , Ayman Alfalou

Direction of arrival (DOA) estimation is mostly performed using specialized arrays that have carefully designed receiver spacing and layouts to match the operating frequency range. In contrast, radio interferometric arrays are designed to…

Instrumentation and Methods for Astrophysics · Physics 2025-12-23 Sarod Yatawatta

Modern radio telescopes, such as the Square Kilometre Array (SKA), will probe the radio sky over large fields-of-view, which results in large w-modulations of the sky image. This effect complicates the relationship between the measured…

Instrumentation and Methods for Astrophysics · Physics 2017-07-14 Arwa Dabbech , Laura Wolz , Luke Pratley , Jason D. McEwen , Yves Wiaux

Scanning electron microscopy with polarization analysis is a powerful lab-based magnetic imaging technique offering parallel imaging of multiple magnetization components and a very high spatial resolution. However, one drawback of the…

Instrumentation and Detectors · Physics 2018-08-22 Daniel Schönke , Andreas Oelsner , Pascal Krautscheid , Robert M. Reeve , Mathias Kläui

The optimal source-finding strategy for linear polarization data is an unsolved problem, with many inhibitive factors imposed by the technically-challenging nature of polarization observations. Such an algorithm is essential for Square…

Instrumentation and Methods for Astrophysics · Physics 2017-12-27 J. S. Farnes , G. Heald , H. Junklewitz , D. D. Mulcahy , M. Haverkorn , C. L. Van Eck , C. J. Riseley , M. Brentjens , C. Horellou , V. Vacca , D. I. Jones , A. Horneffer , R. Paladino

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

Compressive focal plane arrays (FPA) enable cost-effective high-resolution (HR) imaging by acquisition of several multiplexed measurements on a low-resolution (LR) sensor. Multiplexed encoding of the visual scene is typically performed via…

Image and Video Processing · Electrical Eng. & Systems 2023-09-21 Alper Güngör , M. Umut Bahceci , Yasin Ergen , Ahmet Sözak , O. Oner Ekiz , Tolga Yelboga , Tolga Çukur

We propose a new technique to obtain super-resolution images with radio interferometer using sparse modeling. In standard radio interferometry, sampling of ($u$, $v$) is quite often incomplete and thus obtaining an image from observed…

Instrumentation and Methods for Astrophysics · Physics 2014-07-10 Mareki Honma , Kazunori Akiyama , Makoto Uemura , Shiro Ikeda

We describe a new polarized imaging pipeline implemented in the FHD software package. The pipeline is based on the optimal mapmaking imaging approach and performs horizon-to-horizon image reconstruction in all polarization modes. We discuss…

Instrumentation and Methods for Astrophysics · Physics 2022-05-19 Ruby Byrne , Miguel F. Morales , Bryna Hazelton , Ian Sullivan , Nichole Barry

The short-spacing problem describes the inherent inability of radio-interferometric arrays to measure the integrated flux and structure of diffuse emission associated with extended sources. New interferometric arrays, such as SKA, require…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 S. Faridani , F. Bigiel , L. Floeer , J. Kerp , S. Stanimirovic

With ever increasing data rates produced by modern radio telescopes like LOFAR and future telescopes like the SKA, many data processing steps are overwhelmed by the amount of data that needs to be handled using limited compute resources.…

Instrumentation and Methods for Astrophysics · Physics 2020-03-18 Sarod Yatawatta

The integral polarization of spiral galaxies in the radio band has been proposed as a new tracer of the intrinsic galaxy shape that augments lensing shear measurements. We revisit the method of shear estimation in this context. We introduce…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Liang Dai , Junwu Huang , Weichen Winston Yin , Rui Zhou , Simone Ferraro

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

Polarimetric synthetic aperture radar (PolSAR) image classification has been investigated vigorously in various remote sensing applications. However, it is still a challenging task nowadays. One significant barrier lies in the speckle…

Computer Vision and Pattern Recognition · Computer Science 2020-09-15 Haixia Bi , Jing Yao , Zhiqiang Wei , Danfeng Hong , Jocelyn Chanussot

Optical approaches for wavefront shaping traditionally rely on phase modulation through holographic techniques. Shaping the phase determines a wave's diffraction and hence its intensity distribution in space. We instead show that shaping…

The design of an interferometric array should allow optimal instrumental response regarding all possible source positions, times of integration and scientific goals. It should also take into account constraints such as forbidden regions on…

Astrophysics · Physics 2009-11-07 F. Boone