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Related papers: Sub-kilometre scale ionospheric studies at the SKA…

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We search data from the GLEAM-X survey, obtained with the Murchison Widefield Array (MWA) in 2020, for the presence of radio frequency interference from distant Earth-orbiting satellites, in the form of unintended emissions similar to those…

Instrumentation and Methods for Astrophysics · Physics 2025-12-09 S. J. Tingay , N. Hurley-Walker , K. Ross , T. J. Galvin , J. Morgan , B. Venville

The sparsity of millimeter wave (mmWave) channels in the angular and temporal domains is beneficial to channel estimation, while the associated channel parameters can be utilized for localization. However, line-of-sight (LoS) blockage poses…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Kunlun Li , Jiguang He , Mohammed El-Hajjar , Lie-Liang Yang

The Murchison Widefield Array (MWA) is a low-frequency aperture array capable of high-time and frequency resolution astronomy applications such as pulsar studies. The large field-of-view of the MWA (hundreds of square degrees) can also be…

Instrumentation and Methods for Astrophysics · Physics 2022-05-18 N. A. Swainston , N. D. R. Bhat , I. S. Morrison , S. J. McSweeney , S. M. Ord , S. E. Tremblay , M. Sokolowski

The advent of large aperture arrays, such as the ones currently under construction for the SKA project, allows for observing the Universe in the radio-spectrum at unprecedented resolution and sensitivity. To process the enormous amounts of…

Instrumentation and Methods for Astrophysics · Physics 2025-07-31 S. Wang , S. Mignot , S. Prunet , L. Di Mascolo , M. Spinelli , A. Ferrari

Structure imprinted in foreground extragalactic point sources by ionospheric refraction has the potential to contaminate Epoch of Reionisation (EoR) power spectra of the 21~cm emission line of neutral hydrogen. The alteration of the spatial…

The results of a climatological study of ionospheric disturbances derived from observations of cosmic sources from the Very Large Array (VLA) Low-frequency Sky Survey (VLSS) are presented. We have used the ionospheric corrections applied to…

Space Physics · Physics 2015-06-11 J. F. Helmboldt , W. M. Lane , W. D. Cotton

This paper deals with the calibration of the analogue chains of a Square Kilometre Array (SKA) phased aperture array station, using embedded element patterns (one per antenna in the array, thus accounting for the full effects of mutual…

Instrumentation and Methods for Astrophysics · Physics 2020-06-14 Josef Borg , Alessio Magro , Kristian Zarb Adami , Eloy de lera Acedo , Adrian Sutinjo , Daniel Ung

HI intensity mapping (IM) is a novel technique capable of mapping the large-scale structure of the Universe in three dimensions and delivering exquisite constraints on cosmology, by using HI as a biased tracer of the dark matter density…

Future Square Kilometre Array (SKA) surveys are expected to generate huge datasets of 21cm maps on cosmological scales from the Epoch of Reionization (EoR). We assess the viability of exploiting machine learning techniques, namely,…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-13 Sultan Hassan , Sambatra Andrianomena , Caitlin Doughty

Ionospheric irregularities and associated scintillations under geomagnetically active/quiet conditions have detrimental effects on the reliability and performance of space- and ground-based navigation satellite systems, especially over the…

Space Physics · Physics 2024-10-24 Sumanjit Chakraborty , Abhirup Datta

In this chapter we provide an overview of the current status of the simulations and modelling of the Cosmic Dawn and Epoch of Reionization. We discuss the modelling requirements as dictated by the characteristic scales of the problem and…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-20 Ilian T. Iliev , Mario G. Santos , Andrei Mesinger , Suman Majumdar , Garrelt Mellema

Without mitigation, the intrinsic alignment (IA) of galaxies poses a significant threat to achieving unbiased cosmological parameter constraints from precision weak lensing surveys. Here, we apply for the first time to data a method to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-24 Charlie MacMahon-Gellér , C. Danielle Leonard

A first statistical detection of the 21-cm Epoch of Reionization (EoR) is on the horizon, as cosmological volumes of the Universe become accessible via the adoption of low-frequency interferometers. We explore the impact which non-identical…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 A. Chokshi , N. Barry , J. L. B. Line , C. H. Jordan , B. Pindor , R. L. Webster

The magneto-ionic structures of the interstellar medium of the Milky Way and the intergalactic medium are still poorly understood, especially at distances larger than a few kiloparsecs from the Sun. The three-dimensional (3D) structure of…

The low-frequency radio telescope of the Square Kilometre Array (SKA) is being built by the international radio astronomical community to (i) have orders of magnitude higher sensitivity and (ii) be able to map the sky several hundred times…

Instrumentation and Methods for Astrophysics · Physics 2023-05-29 Agaram Raghunathan , Keerthipriya Satish , Arasi Sathyamurthy , T. Prabu , B. S. Girish , K. S. Srivani , Shiv K. Sethi

Phase referencing is a standard calibration procedure in radio interferometry. It allows to detect weak sources by using quasi-simultaneous observations of closeby sources acting as calibrators. Therefore, it is assumed that, for each…

Instrumentation and Methods for Astrophysics · Physics 2011-01-25 I. Marti-Vidal , J. C. Guirado , S. Jimenez-Monferrer , J. M. Marcaide

Low-frequency spectral studies of radio pulsars represent a key method for uncovering their emission mechanisms, magnetospheric structure, and signal interactions with the surrounding interstellar medium (ISM). In recent years, more…

Astrophysics of Galaxies · Physics 2025-10-13 Ting Yu , Zhongli Zhang , Hongyu Gong , Zhigang Wen

Millimeter-Wave (mm-Wave) frequency bands provide an opportunity for much wider channel bandwidth compared with the traditional sub-6 GHz band. Communication at mm-Waves is, however, quite challenging due to the severe propagation path…

Information Theory · Computer Science 2017-10-19 Xiaoshen Song , Saeid Haghighatshoar , Giuseppe Caire

The imprint of baryon acoustic oscillations (BAO) in large-scale structure can be used as a standard ruler for mapping out the cosmic expansion history, and hence for testing cosmological models. In this article we briefly describe the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Philip Bull , Stefano Camera , Alvise Raccanelli , Chris Blake , Pedro G. Ferreira , Mario G. Santos , Dominik J. Schwarz

The Square Kilometre Array (SKA) is the largest radio interferometer under construction in the world. The high accuracy, wide-field and large size imaging significantly challenge the construction of the Science Data Processor (SDP) of SKA.…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Yangfan Xie , Feng Wang , Hui Deng , Ying Mei , Ying-He Celeste Lu , Gabriella Hodosan , Vladislav Stolyarov , Oleg Smirnov , Xiaofeng Li , Tim Cornwell
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