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Related papers: Wide field imaging for the Square Kilometre Array

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Wide-field imaging has become a major challenge for modern radio astronomy, which uses high sensitivity acquisition systems that deal with huge amounts of data. In this paper we investigate a fast wide-field imaging solution based on the…

Instrumentation and Methods for Astrophysics · Physics 2019-04-19 Luis F. R. Lucas , Chris J. Skipper , Anna M. M. Scaife

Modern image formation algorithms in radio interferometry rely on repeated applications of the operator {\Phi} modelling the measurement process and its adjoint {Phi^\dagger} to enforce consistency with the acquired data, specifically via…

Instrumentation and Methods for Astrophysics · Physics 2026-05-27 Arwa Dabbech , Yves Wiaux

Large radio telescopes in the 21st century such as the Low-Frequency Array (LOFAR) or the Murchison Widefield Array (MWA) make use of phased aperture arrays of antennas to achieve superb survey speeds. The Square Kilometer Array low…

Instrumentation and Methods for Astrophysics · Physics 2017-12-06 Ha Bui-Van , Christophe Craeye , Eloy de Lera Acedo

After several generations of interferometers in radioastronomy, wide-field imaging at high angular resolution is today a major goal for trying to match optical wide-field performances. All the radio-interferometric, wide-field imaging…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Jérôme Pety , Nemesio J. Rodriguez-Fernandez

We describe a scalable distributed imaging algorithm framework for next-generation radio telescopes, managing the Fourier transform from apertures to sky (or vice versa) with a focus on minimising memory load, data transfers, and…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 Peter Wortmann , James Kent , Bojan Nikolic

Accurate channel parameter estimation is challenging for wideband millimeter-wave (mmWave) large-scale hybrid arrays, due to beam squint and much fewer radio frequency (RF) chains than antennas. This paper presents a novel joint delay and…

Information Theory · Computer Science 2021-02-23 Zhipeng Lin , Tiejun Lv , Wei Ni , J. Andrew Zhang , Jie Zeng , Ren Ping Liu

Interferometric Synthetic Aperture Radar (InSAR) Imaging methods are usually based on algorithms of match-filtering type, without considering the scene's characteristic, which causes limited imaging quality. Besides, post-processing steps…

Signal Processing · Electrical Eng. & Systems 2022-10-07 Xu Zhan , Xiaoling Zhang , Shunjun Wei , Jun Shi

Wide-field images made by radio interferometers are invariably affected by direction-dependent systematic effects such as the ionosphere or the beam pattern. Calibration along a set of discrete directions in the sky is the default technique…

Instrumentation and Methods for Astrophysics · Physics 2026-02-06 Sebastiaan van der Tol , Sarod Yatawatta , Bram Veenboer , David Rafferty

Channel estimation is essential for precoding/combining in millimeter wave (mmWave) communications. However, accurate estimation is usually difficult because the receiver can only observe the low-dimensional projection of the received…

Information Theory · Computer Science 2018-08-30 Xiaohuan Wu , Wei-Ping Zhu , Min Lin , Jun Yan

In this paper, we implement hybrid Woodward-Lawson-Neural Networks and weighted Fourier method to synthesize antenna arrays. The neural networks (NN) is applied here to simplify the modeling of MIMO antenna arrays by assessing phases. The…

Signal Processing · Electrical Eng. & Systems 2019-12-03 Elies Ghayoula , Ridha Ghayoula , Jaouhar Fattahi , Emil Pricop , Jean-Yves Chouinard , Ammar Bouallegue

Hyperspectral imaging is useful for applications ranging from medical diagnostics to agricultural crop monitoring; however, traditional scanning hyperspectral imagers are prohibitively slow and expensive for widespread adoption. Snapshot…

Image and Video Processing · Electrical Eng. & Systems 2020-09-30 Kristina Monakhova , Kyrollos Yanny , Neerja Aggarwal , Laura Waller

Large-format (sub)millimeter wavelength imaging arrays are best operated in scanning observing modes rather than traditional position-switched (chopped) modes. The choice of observing mode is critical for isolating source signals from…

Astrophysics · Physics 2014-11-18 A. Kovacs

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

Current and upcoming radio-interferometers are expected to produce volumes of data of increasing size that need to be processed in order to generate the corresponding sky brightness distributions through imaging. This represents an…

Instrumentation and Methods for Astrophysics · Physics 2023-01-18 Claudio Gheller , Giuliano Taffoni , David Goz

Millimeter-wave (MMW) imaging has a wide prospect in application of concealed weapons detection. We propose a circular-arc multiple-input multiple-output (MIMO) array scheme with uniformly spaced transmit and receive antennas along the…

Signal Processing · Electrical Eng. & Systems 2021-03-01 Shiyong Li , Shuoguang Wang , Guoqiang Zhao , Houjun Sun

This paper is concerned with the channel estimation problem in millimetre wave (MMW) wireless systems with large antenna arrays. By exploiting the sparse nature of the MMW channel, we present an efficient estimation algorithm based on a…

Information Theory · Computer Science 2018-04-19 Matthew Kokshoorn , Peng Wang , Yonghui Li , Branka Vucetic

Noncoherent communication systems have regained interest due to the growing demand for high-mobility and low-latency applications. Most existing studies using large antenna arrays rely on the far-field approximation, which assumes locally…

Signal Processing · Electrical Eng. & Systems 2025-05-26 Aniol Martí , Luca Sanguinetti , Meritxell Lamarca , Jaume Riba

Radio interferometry most commonly involves antennas or antenna arrays of identical design. The identical antenna assumption leads to a convenient and useful mathematical simplification resulting in a scalar problem. An interesting variant…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Adrian T. Sutinjo , Daniel Ung , Tim M. Colegate , Randall B. Wayth , Peter J. Hall , Eloy de Lera Acedo

As a promising technique, extremely large-scale (XL)-arrays offer potential solutions for overcoming the severe path loss in millimeter-wave (mmWave) and TeraHertz (THz) channels, crucial for enabling 6G. Nevertheless, XL-arrays introduce…

Signal Processing · Electrical Eng. & Systems 2023-09-19 Songjie Yang , Wanting Lyu , Zhongpei Zhang , Chau Yuen

Classical single-mode fiber interferometers, using one fiber per aperture, have very limited imaging capabilities and small field of view. Observations of extended sources (resolved by one aperture) cannot be fully corrected for wavefront…

Astrophysics · Physics 2009-11-07 Olivier Guyon