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Related papers: Antenna array characterization via radio interfero…

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In this paper, we propose a new type of array antenna, termed the Random Frequency Diverse Array (RFDA), for an uncoupled indication of target direction and range with low system complexity. In RFDA, each array element has a narrow…

Information Theory · Computer Science 2017-04-05 Yimin Liu , Hang Ruan , Lei Wang , Arye Nehorai

The present constraints on fundamental constant variation (\alpha and \mu) obtained in the radio range are reviewed, coming essentially from absorption lines in front of quasars of intermediate to high-z galaxies, through CO, HI, OH, HCO+,…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-06 F. Combes

The visibilities measured by radio astronomical interferometers include non-astronomical correlated signals that arise from the local environment of the array. These correlated signals are especially important in compact arrays such as…

Instrumentation and Methods for Astrophysics · Physics 2023-11-08 Juhun Kwak , John Podczerwinski , Peter Timbie , Réza Ansari , John Marriner , Albert Stebbins , Fengquan Wu , Haotian Cao , Xuelei Chen , Kai He , Jixia Li , Shijie Sun , Jiacong Zhu

This work considers detecting the presence of a band-limited random radio source using an antenna array featuring a low-complexity digitization process with single-bit output resolution. In contrast to high-resolution analog-to-digital…

Information Theory · Computer Science 2018-02-21 Manuel S. Stein

Infrared-faint radio sources (IFRS) are objects that have flux densities of several mJy at 1.4GHz, but that are invisible at 3.6um when using sensitive Spitzer observations with uJy sensitivities. Their nature is unclear and difficult to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Enno Middelberg , Ray P. Norris , Christopher A. Hales , Nick Seymour , Melanie Johnston-Hollitt , Minh T. Huynh , Emil Lenc , Minnie Y. Mao

Astrometry provides the foundation for astrophysics. Accurate positions are required for the association of sources detected at different times or wavelengths, and distances are essential to estimate the size, luminosity, mass, and ages of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 M. J. Reid , M. Honma

Detection and mitigation of radio frequency interference (RFI) is the first and also the key step for data processing in radio observations, especially for ongoing low frequency radio experiments towards the detection of the cosmic dawn and…

Instrumentation and Methods for Astrophysics · Physics 2016-03-02 Yan Huang , Xiang-Ping Wu , Qian Zheng , Jun-Hua Gu , Haiguang Xu

The LOw Frequency ARray (LOFAR) has successfully measured cosmic rays for over a decade now. With its dense core of antenna fields in the Netherlands, it is an ideal tool for studying the radio emission from extensive air showers in the…

Redundant calibration is a technique in radio astronomy that allows calibration of radio arrays whose antennas lie on a lattice by exploiting the fact that redundant baselines should see the same sky signal. Because the number of measured…

Instrumentation and Methods for Astrophysics · Physics 2022-08-17 Prakruth Adari , Anže Slosar

The Laser Interferometer Space Antenna is a foreseen gravitational wave detector, which aims to detect $10^{-20}$ strains in the frequency range from 0.1 mHz to 1 Hz. It is a triangular constellation, with equal sides of $2,5 \times 10^9$…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 C P Sasso , G Mana , S Mottini

The radio astronomy community is currently building a number of phased array telescopes. The calibration of these telescopes is hampered by the fact that covariances of signals from closely spaced antennas are sensitive to noise coupling…

Instrumentation and Methods for Astrophysics · Physics 2010-03-15 Stefan J. Wijnholds , Alle-Jan van der Veen

The redshifted 21-cm monopole is expected to be a powerful probe of the epoch of the first stars and galaxies ($10<z<35$). The global 21-cm signal is sensitive to the thermal and ionization state of hydrogen gas and thus provides a tracer…

This paper presents a method for estimating the characteristics of a diffuse source from interferometric measurements in the context of SAR tomography. The proposed method is based on the use of central moments of the reflectivity density…

Signal Processing · Electrical Eng. & Systems 2025-03-31 Colin Cros , Laurent Ferro-Famil

Detecting gravitational wave bursts (characterised by short durations and poorly modelled waveforms) requires to have coincidences between several interferometric detectors in order to reject non-stationary noise events. As the wave…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Nicolas Arnaud , Matteo Barsuglia , Marie-Anne Bizouard , Philippe Canitrot , Fabien Cavalier , Michel Davier , Patrice Hello , Thierry Pradier

The response of a gravitational-wave (GW) interferometer is spatially modulated and is described by two antenna patterns, one for each polarization state of the waves. The antenna patterns are derived from the shape and size of the…

General Relativity and Quantum Cosmology · Physics 2025-03-21 Andrea Virtuoso , Edoardo Milotti

Faraday tomography, the study of the distribution of extended polarized emission by strength of Faraday rotation, is a powerful tool for studying magnetic fields in the interstellar medium of our Galaxy and nearby galaxies. The strong…

Astrophysics of Galaxies · Physics 2018-10-24 Cameron L. Van Eck

Hubble Space Telescope images are presented of a sample of 28 3CR radio galaxies with redshifts in the range 0.6 < z < 1.8, together with maps at comparable angular resolution of their radio structure, taken using the Very Large Array.…

Astrophysics · Physics 2015-06-24 P. N. Best , M. S. Longair , H. J. A. R"ottgering

This proceeding gives a summary of the current status and open questions of the radio technique for cosmic-ray air showers, assuming that the reader is already familiar with the principles. It includes recent results of selected experiments…

High Energy Astrophysical Phenomena · Physics 2017-03-20 Frank G. Schröder

The Multipurpose Interferometer Array Pathfinder (MIA), developed from the Argentine Institute of Radio Astronomy (IAR), is a radio astronomical instrument based on interferometry techniques, designed for the detection of radio emission…

Instrumentation and Methods for Astrophysics · Physics 2023-12-29 J. M. Gonzalez , H. Command , G. Valdez

Radio Frequency Interference (RFI) increasingly contaminates the radio astronomy spectrum, often exceeding astronomical signal amplitudes by 50-70 dB. Reliable detection and mitigation are therefore essential for studies of faint transient…

Instrumentation and Methods for Astrophysics · Physics 2026-05-08 Natalia A. Schmid , Sasanka Katreddi , Yechan Kweon