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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

One approach to extracting the global 21-cm signal from total-power measurements at low radio frequencies is to parametrize the different contributions to the data and then fit for these parameters. We examine parametrizations of the 21-cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-04 Geraint J. A. Harker , Jordan Mirocha , Jack O. Burns , Jonathan R. Pritchard

The next generation instrument for ground-based gamma-ray astronomy will be the Cherenkov Telescope Array (CTA), consisting of approximately 100 telescopes in three sizes, built on two sites with one each in the Northern and Southern Hemi-…

Instrumentation and Methods for Astrophysics · Physics 2017-08-09 Louise Oakes , Markus Garczarczyk , Stephan Kaphle , Michael Mayer , Stefan Schlenstedt

We present a technique for the accurate estimation of large-scale errors in an antenna surface using astronomical sources and detectors. The technique requires several out-of-focus images of a compact source and the signal-to-noise ratio…

Astrophysics · Physics 2009-11-11 B. Nikolic , R. E. Hills , J. S. Richer

Weak gravitational lensing measurements are traditionally made at optical wavelengths where many highly resolved galaxy images are readily available. However, the Square Kilometre Array (SKA) holds great promise for this type of measurement…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-19 Prina Patel , Ian Harrison , Sphesihle Makhathini , Filipe Abdalla , David Bacon , Michael L. Brown , Ian Heywood , Matt Jarvis , Oleg Smirnov

The Simons Observatory is a ground-based telescope array located at an elevation of 5200 meters, in the Atacama Desert in Chile, designed to measure the temperature and polarization of the cosmic microwave background. It comprises four…

The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long…

We present the design of the prototype telescope and spectrograph system for the Affordable Multiple Aperture Spectroscopy Explorer (AMASE) project. AMASE is a planned project that will pair 100 identical multi-fiber spectrographs with a…

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

Imaging the low-frequency radio Sun is an intrinsically challenging problem. Meter-wavelength solar emission spans angular scales from a few arcminutes to a few degrees. These emissions show temporal and spectral variability on a sub-second…

Solar and Stellar Astrophysics · Physics 2022-09-22 Devojyoti Kansabanik

Extremely large antenna arrays (ELAAs) can provide higher spectral efficiency. However, the use of narrower beams for data transmission significantly increases the overhead associated with beam training. In this letter, we propose a novel…

Signal Processing · Electrical Eng. & Systems 2024-06-04 Hongkang Yu , Yuan Si , Shujuan Zhang , Yijian Chen

A method for estimating the axis of reflectional symmetry of an image $f(x,y)$ on the unit disc $D=\{(x,y):x^2+y^2\leq1\}$ is proposed, given that noisy data of $f(x,y)$ are observed on a discrete grid of edge width $\Delta$. Our estimation…

Applications · Statistics 2011-02-04 Nicolai Bissantz , Hajo Holzmann , Mirosław Pawlak

We propose an all-digital telescope for 21 cm tomography, which combines key advantages of both single dishes and interferometers. The electric field is digitized by antennas on a rectangular grid, after which a series of Fast Fourier…

Astrophysics · Physics 2009-10-29 Max Tegmark , Matias Zaldarriaga

Kilometric-scale optical imagers seem feasible to realize by intensity interferometry, using telescopes primarily erected for measuring Cherenkov light induced by gamma rays. Planned arrays envision 50--100 telescopes, distributed over some…

Instrumentation and Methods for Astrophysics · Physics 2010-09-30 Hannes Jensen , Dainis Dravins , Stephan LeBohec , Paul D. Nuñez

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

Type Ia supernovae are the most direct cosmological probe to study dark energy in the recent Universe, for which the photometric calibration of astronomical instruments remains one major source of systematic uncertainties. To address this,…

Instrumentation and Methods for Astrophysics · Physics 2024-03-05 K. Sommer , J. Cohen-Tanugi , B. Plez , M. Betoule , S. Bongard , L. Le Guillou , J. Neveu , E. Nuss , E. Sepulveda , T. Souverin , M. Moniez , C. W. Stubbs

Analog beamforming holds great potential for future terahertz (THz) communications due to its ability to generate high-gain directional beams with low-cost phase shifters. However, conventional analog beamforming may suffer substantial…

Signal Processing · Electrical Eng. & Systems 2026-03-26 Yike Xie , Weidong Mei , Dong Wang , Yingqi Wen , Zhi Chen , Jun Fang , Wei Guo , Boyu Ning

We present the antenna design for a radio interferometer, the Arcminute Microkelvin Imager, together with its beam pattern measurement. Our aim was to develop a low-cost system with high aperture efficiency and low ground-spill across the…

Astrophysics · Physics 2011-12-12 C. M. Holler , R. E. Hills , M. E. Jones , K. Grainge , T. Kaneko

Transmission electron microscopes (TEMs) enable atomic-scale imaging but suffer from aberrations caused by lens imperfections and environmental conditions, reducing image quality. These aberrations can be compensated by adjusting…

Systems and Control · Electrical Eng. & Systems 2026-04-20 Jilles S. van Hulst , Erik M. Franken , Bart J. Janssen , W. P. M. H. Heemels , Duarte J. Antunes

Sensitivity and resolution of space telescopes are directly related to the size of the primary mirror. Enabling such future extremely large space telescopes or even arrays of those will require to drastically reduce the areal weight of the…

Instrumentation and Methods for Astrophysics · Physics 2024-10-11 S. Rabien , L. Busoni , C. Del Vecchio , J. Ziegleder , S. Esposito