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Image alignment plays a crucial role in solar physics research, primarily involving translation, rotation, and scaling. \G{The different wavelength images of the chromosphere and transition region have structural complexity and differences…

Instrumentation and Methods for Astrophysics · Physics 2025-03-17 Yun Wang , KaiFan Ji , Zhenyu Jin , Hui Liu

We present a broadband map of polarized diffuse emission at 167-198 MHz developed from data from the Murchison Widefield Array (MWA). The map is designed to improve visibility simulation and precision calibration for 21 cm Epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Ruby Byrne , Miguel F. Morales , Bryna Hazelton , Ian Sullivan , Nichole Barry , Christene Lynch , Jack L. B. Line , Daniel C. Jacobs

Next generation radio observatories such as the MWA, LWA, LOFAR, CARMA and SKA provide a number of challenges for interferometric data analysis. These challenges include heterogeneous arrays, direction-dependent instrumental gain, and…

Astrophysics · Physics 2015-05-13 Miguel F. Morales , Michael Matejek

The Murchison Widefield Array is a low-frequency Square Kilometre Array precursor located at the Murchison Radio-astronomy Observatory in Western Australia. Primarily designed as an imaging telescope, but with a flexible signal path, the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-15 S. M. Ord , S. E. Tremblay , S. J. McSweeney , N. D. R. Bhat , C. Sobey , D. A. Mitchell , P. J. Hancock , F. Kirsten

In this article, we introduce a novel algorithm for efficient near-field synthetic aperture radar (SAR) imaging for irregular scanning geometries. With the emergence of fifth-generation (5G) millimeter-wave (mmWave) devices, near-field SAR…

Signal Processing · Electrical Eng. & Systems 2023-05-04 Josiah Smith , Murat Torlak

Bodies such as planets, moons, and asteroids in our solar system are the brightest objects in the low-frequency radio astronomy at $\lesssim$ 10 GHz. The low-frequency radio emissions from our solar system bodies exhibit various observed…

Earth and Planetary Astrophysics · Physics 2023-03-15 Tomoki Kimura , Yuka Fujii , Hajime Kita , Fuminori Tsuchiya , Hideo Sagawa , the SKA-Japan Planetary Science Team

We test the bandpass smoothness performance of two prototype Square Kilometre Array (SKA) SKA1-Low log-periodic dipole antennas, the SKALA2 and SKALA3 (`SKA Log-periodic Antenna'), and the current dipole from the Murchison Widefield Array…

Instrumentation and Methods for Astrophysics · Physics 2017-06-28 Cathryn M. Trott , Eloy de Lera Acedo , Randall B. Wayth , Nicolas Fagnoni , Adrian T. Sutinjo , Brett Wakley , Chris Ivan B. Punzalan

As Part I of a paper series showcasing a new imaging framework, we consider the recently proposed unconstrained Sparsity Averaging Reweighted Analysis (uSARA) optimisation algorithm for wide-field, high-resolution, high-dynamic range,…

Instrumentation and Methods for Astrophysics · Physics 2023-09-11 Amanda G. Wilber , Arwa Dabbech , Adrian Jackson , Yves Wiaux

The Low Frequency Array (LOFAR) is an ideal instrument to conduct deep extragalactic surveys. It has a large field of view and is sensitive to large scale and compact emission. It is, however, very challenging to synthesize thermal noise…

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

Millimter (mm) frequencies are primarily sensitive to thermal emission from layers across the stellar chromosphere up to the transition region, while metrewave (radio) frequencies probe the coronal heights. Together the mm and radio band…

Solar and Stellar Astrophysics · Physics 2025-10-16 Atul Mohan

Solar radio emissions offer unique diagnostic insights into the solar corona. However, their dynamic and multiscale nature, along with several orders of magnitude variations in intensity, pose significant observational challenges. To date,…

The Murchison Widefield Array (MWA) is a next-generation radio telescope, generating visibility data products continuously at about 400 MB/s. Efficiently managing and archiving this data is a challenge. The MWA Archive consists of dataflows…

Instrumentation and Methods for Astrophysics · Physics 2013-08-29 Chen Wu , Andreas Wicenec , Dave Pallot , Alessio Checcucci

Solar radio observations provide a unique diagnostic of the outer solar atmosphere. However, the inhomogeneous turbulent corona strongly affects the propagation of the emitted radio waves, so decoupling the intrinsic properties of the…

Solar and Stellar Astrophysics · Physics 2018-02-22 E. P. Kontar , S. Yu , A. A. Kuznetsov , A. G. Emslie , B. Alcock , N. L. S. Jeffrey , V. N. Melnik , N. H. Bian , P. Subramanian

Multiple-input multiple-output (MIMO) array based millimeter-wave (MMW) imaging has a tangible prospect in applications of concealed weapons detection. A near-field imaging algorithm based on wavenumber domain processing is proposed for a…

Signal Processing · Electrical Eng. & Systems 2021-01-25 Shiyong Li , Shuoguang Wang , Moeness G. Amin , Guoqiang Zhao

Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; the formation and eruption of prominences and filaments; and…

The ambitious scientific goals of the SKA require a matching capability for calibration of atmospheric propagation errors, which contaminate the observed signals. We demonstrate a scheme for correcting the direction-dependent ionospheric…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 Maria Rioja , Richard Dodson , Thomas Franzen

The Murchison Widefield Array (MWA) is a next-generation radio telescope currently under construction in the remote Western Australia Outback. Raw data will be generated continuously at 5GiB/s, grouped into 8s cadences. This high throughput…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 R. G. Edgar , M. A. Clark , K. Dale , D. A. Mitchell , S. M. Ord , R. B. Wayth , H. Pfister , L. J. Greenhill

This paper describes the use of the Murchison Widefield Array, a low-frequency radio telescope at a radio-quiet Western Australian site, as a radar receiver forming part of a continent-spanning multistatic radar network for the surveillance…

Signal Processing · Electrical Eng. & Systems 2022-06-07 Brendan Hennessy , Robert Young , Steven Tingay , Ashley Summers , Daniel Gustainis , Brian Crosse , Marcin Sokolowski

The very nature of the solar chromosphere, its structuring and dynamics, remains far from being properly understood, in spite of intensive research. Here we point out the potential of chromospheric observations at millimeter wavelengths to…

Astrophysics · Physics 2009-06-23 M. A. Loukitcheva , S. K. Solanki , S. White