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Related papers: Imaging at 300 MHz With the MWA

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An experimental evidence of subwavelength imaging with a "lens", which is a uniaxial negative permittivity wire medium slab, is reported. The slab is formed by gratings of long thin parallel conducting cylinders. Taking into account the…

Periodic multilayers are nowadays widely used to perform x-ray analysis in the soft x-ray range (photon energy lower than 1 keV). However, they do not permit to obtain high-resolution spectra like natural or synthetic crystals. Thus,…

Instrumentation and Detectors · Physics 2013-04-08 Philippe Jonnard , Karine Le Guen , Jean-Michel André

The ngVLA is a new interferometric radio astronomy facility with transformative capabilities, being developed by the National Radio Astronomy Observatory. It combines two orders of magnitude in frequency coverage, over 1.2 - 116 GHz, with…

Instrumentation and Methods for Astrophysics · Physics 2025-04-22 T. K. Sridharan , S. Bhatnagar , P. Jagannathan , K. Golap

Although several existing and upcoming telescopes have imaging as their primary mode, they also have a sensitive phased-array mode with a multiple-beam forming capability enabling high time resolution studies of several types of objects,…

Instrumentation and Methods for Astrophysics · Physics 2010-01-29 Jayanth Chennamangalam , Yogesh Maan , Avinash A. Deshpande

The QUIJOTE MFI instrument (2012-2018) observed the sky at four frequency bands, namely 11, 13, 17 and 19GHz, at 1 degree angular resolution. Using around 10000 h of observations in the so-called nominal mode, QUIJOTE MFI produced sky maps…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-16 Apolline Chappard , José Alberto Rubiño-Martín , Ricardo Tanausú Génova-Santos

We describe a 325-MHz survey, undertaken with the Giant Metrewave Radio Telescope (GMRT), which covers a large part of the three equatorial fields at 9, 12 and 14.5 h of right ascension from the Herschel-Astrophysical Terahertz Large Area…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 T. Mauch , H. -R. Klöckner , S. Rawlings , M. J. Jarvis , M. J. Hardcastle , D. Obreschkow , D. J. Saikia , M. A. Thompson

We examine data from the Murchison Widefield Array (MWA) in the frequency range 72 -- 102 MHz for a field-of-view that serendipitously contained the interstellar object 'Oumuamua on 2017 November 28. Observations took place with time…

The high sensitivity of the new generation of radio telescopes such as the Square Kilometre Array (SKA) will allow cosmological weak lensing measurements at radio wavelengths that are competitive with optical surveys. We present an…

Instrumentation and Methods for Astrophysics · Physics 2016-09-23 Marzia Rivi , Lance Miller , Sphesihle Makhathini , Filipe Batoni Abdalla

The millimeter wave (mmWave) frequencies offer the potential for enormous capacity wireless links. However, designing robust communication systems at these frequencies requires that we understand the channel dynamics over both time and…

Signal Processing · Electrical Eng. & Systems 2017-12-18 Christopher Slezak , Aditya Dhananjay , Sundeep Rangan

Recent work has successfully achieved sub-arcsecond wide-field imaging with high-band observations from the Low Frequency Array (LOFAR). However, the scalability of this work remains limited due to the need for manual intervention, poor…

Increasing attention is being paid to millimeter-wave (mmWave), 30 GHz to 300 GHz, and terahertz (THz), 300 GHz to 10 THz, sensing applications including security sensing, industrial packaging, medical imaging, and non-destructive testing.…

Signal Processing · Electrical Eng. & Systems 2023-06-28 Josiah Smith

High sensitivity observations of radio halos in galaxy clusters at frequencies lower than 330 MHz are still relatively rare, and very little is known compared to the classical 1.4 GHz images. The few radio halos imaged down to 150-240 MHz…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 T. Venturi , S. Giacintucci , D. Dallacasa

In this work, we propose a novel approach for high accuracy user localization by merging tools from both millimeter wave (mmWave) imaging and communications. The key idea of the proposed solution is to leverage mmWave imaging to construct a…

Information Theory · Computer Science 2018-11-20 Mohammed Aladsani , Ahmed Alkhateeb , Georgios C. Trichopoulos

Millimeter-wave (mmWave) radar systems, owing to their large bandwidth, provide fine range resolution that enables the observation of multiple scatterers originating from a single automotive target, commonly referred to as an extended…

Signal Processing · Electrical Eng. & Systems 2025-11-21 Vinay Kulkarni , V. V. Reddy

Low-frequency radio surveys allow in-depth studies and new analyses of classes of sources previously known and characterised only in other bands. In recent years, low radio frequency observations of blazars have been available thanks to new…

Astrophysics of Galaxies · Physics 2020-01-08 Daniele d'Antonio , Marcello Giroletti , Gabriele Giovannini , Alessandro Maini

An experimental investigation of sub-wavelength imaging by a wire medium slab is performed. A complex-shaped near field source is used in order to test imaging performance of the device. It is demonstrated that the ultimate bandwidth of…

Materials Science · Physics 2015-06-25 Pavel A. Belov , Yan Zhao , Sunil Sudhakaran , Akram Alomainy , Yang Hao

The Low Frequency Array (LOFAR) is uniquely able to perform deep, 15" resolutions imaging at frequencies below 100 MHz. Observations in this regime, using the Low Band Antenna (LBA) system, are significantly affected by instrumental and…

Astrophysics of Galaxies · Physics 2026-01-14 J. M. Boxelaar , F. De Gasperin , M. J. Hardcastle , J. H. Croston , L. K. Morabito , R. J. van Weeren , H. Edler

The rapid growth of global data traffic is accelerating the need for ultra-broadband communication technologies, particularly in cloud infrastructure and emerging 6G wireless systems. Optical computing and quantum information processing…

Using a Ramsey-type setup, the lambda-doublet transition in the $J=1,\, \Omega=1$ level of the $a^3\Pi$ state of CO was measured to be 394 064 870(10) Hz. In our molecular beam apparatus, a beam of metastable CO is prepared in a single…

Chemical Physics · Physics 2015-06-19 A. J. de Nijs , W. Ubachs , H. L. Bethlem

LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short…

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