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Related papers: Calibration of an SKA-Low Prototype Station Using …

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A revolution in radio receiving technology is underway with the development of densely packed phased arrays for radio astronomy. This technology can provide an exceptionally large field of view, while at the same time sampling the sky with…

Instrumentation and Methods for Astrophysics · Physics 2016-03-03 S. A. Torchinsky , A. O. H. Olofsson , B. Censier , A. Karastergiou , M. Serylak , P. Renaud , C. Taffoureau

A fast full-wave simulation technique is presented for the analysis of large irregular planar arrays of identical 3-D metallic antennas. The solution method relies on the Macro Basis Functions (MBF) approach and an interpolatory technique…

Instrumentation and Methods for Astrophysics · Physics 2018-05-09 Ha Bui-Van , Jens Abraham , Michel Arts , Quentin Gueuning , Christopher Raucy , David Gonzalez-Ovejero , Eloy de Lera Acedo , Christophe Craeye

A single-pixel digital holography system with phase-encoded illumination using a digital micromirror device (DMD) as a spatial light modulator (SLM) is presented. The enhanced switching rate of DMDs, far exceeding the stringent frame-rate…

This paper describes the technical details and practical implementation of the Mid-Frequency Square Kilometre Array (SKA) phase synchronisation system. Over a four-year period, the system has been tested on metropolitan fibre-optic…

Instrumentation and Methods for Astrophysics · Physics 2019-02-27 Sascha Schediwy , David Gozzard , Charles Gravestock , Simon Stobie , Richard Whitaker , Jocias Malan , Paul Boven , Keith Grainge

The Mingantu Spectral Radioheliograph (MUSER), a new generation of solar dedicated radio imaging-spectroscopic telescope, has realized high-time, high-angular, and high-frequency resolution imaging of the sun over an ultra-broadband…

Instrumentation and Methods for Astrophysics · Physics 2022-10-17 Zhichao Zhou , Yihua Yan , Linjie Chen , Wei Wang , Suli Ma

Integrated sensing and communication (ISAC) can perform both communication and sensing tasks using the same frequency band and hardware, making it a key technology for 6G. As a low-cost implementation for large-scale antenna arrays,…

Signal Processing · Electrical Eng. & Systems 2026-02-04 Shupei Zhang , Shuhao Zeng , Boya Di , Lingyang Song

The Square Kilometre Array (SKA) is a proposed next generation radio telescope. Between now and 2005 this project is in a technology development and prototyping phase, with construction likely to begin in $\sim 2010$. This paper describes…

Astrophysics · Physics 2007-05-23 J. F. Bell

Holographic multiple-input multiple-output (MIMO) systems constitute a promising technology in support of next-generation wireless communications, thus paving the way for a smart programmable radio environment. However, despite its…

Information Theory · Computer Science 2024-05-28 Yuanbin Chen , Ying Wang , Zhaocheng Wang , Ping Zhang

We present a survey strategy to detect the neutral hydrogen (HI) power spectrum at $5<z<6$ using the SKA-Low radio telescope in presence of foregrounds and instrumental effects. We simulate observations of the inherently weak HI signal…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-27 Zhaoting Chen , Emma Chapman , Laura Wolz , Aishrila Mazumder

A new method for absolute polarimetric calibration of large telescopes is presented. The proposed method is highly accurate and is based on the calibration of a small sub-aperture, which is then extended to the full system by means of…

Astrophysics · Physics 2009-11-10 H. Socas-Navarro

Polarisation holography generally demands polarisation-sensitive holograms for reconstructing either polarisation-multiplexed holographic images or polarisation-sensitive image channels. To date, polarisation holography is underpinned by…

Optics · Physics 2022-07-22 Haoran Ren

The Square Kilometre Array (SKA) will have a low frequency component (SKA-low) which has as one of its main science goals the study of the redshifted 21cm line from the earliest phases of star and galaxy formation in the Universe. This 21cm…

We apply a novel method with machine learning to calibrate sub-grid models within numerical simulation codes to achieve convergence with observations and between different codes. It utilizes active learning and neural density estimators.…

Astrophysics of Galaxies · Physics 2022-10-07 Boon Kiat Oh , Hongjun An , Eun-jin Shin , Ji-hoon Kim , Sungwook E. Hong

In this paper, we propose a beamforming method for the calibration of the direction-independent gain of the analog chains of aperture arrays. The gain estimates are obtained by cross-correlating the output voltage of each antenna with a…

Instrumentation and Methods for Astrophysics · Physics 2020-05-26 Quentin Gueuning , Antony Brown , Christophe Craeye , Eloy de Lera Acedo

The Square Kilometre Array (SKA) will be the first low-frequency instrument with the capability to directly image the structures of the Epoch of Reionization (EoR). Indeed, deep imaging of the EoR over 5 targeted fields of 20 square degrees…

Instrumentation and Methods for Astrophysics · Physics 2021-03-31 Qian Zheng , Xiang-Ping Wu , Quan Guo , Melanie Johnston-Hollitt , Huanyuan Shan , Stefan W. Duchesne , Weitian Li

Lensless in-line holography is a simple, portable, and cost-effective method of imaging especially for the biomedical microscopy applications. We propose a multiplicative gradient descent optimization based method to obtain multi-depth…

Image and Video Processing · Electrical Eng. & Systems 2020-04-20 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

We discuss the unique opportunities for maser astrometry with the inclusion of the Square Kilometre Array (SKA) in Very Long Baseline Interferometry (VLBI) networks. The first phase of the SKA will enable observations of hydroxyl and…

Calibration of a sensor array is more involved if the antennas have direction dependent gains and multiple calibrator sources are simultaneously present. We study this case for a sensor array with arbitrary geometry but identical elements,…

Instrumentation and Methods for Astrophysics · Physics 2010-03-10 Stefan J. Wijnholds , Alle-Jan van der Veen

This study investigates the sensitivity of the radio interferometers to identify imprints of spatially inhomogeneous dark matter annihilation signatures in the 21-cm signal during the pre-reionization era. We focus on the upcoming low-mode…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-28 Pravin Kumar Natwariya , Kenji Kadota , Atsushi J. Nishizawa

While characterization of coherent wavefields is essential to laser, x-ray and electron imaging, sensors measure the squared magnitude of the field, rather than the field itself. Holography or phase retrieval must be used to characterize…

Image and Video Processing · Electrical Eng. & Systems 2020-12-10 David J. Brady , Timothy J. Schulz , Chengyu Wang