Results 31 to 40 of about 11,173,939 (282)

The Radio Astronomy Explorer Satellite, a Low‐Frequency Observatory [PDF]

Radio Science, 1971
The Radio Astronomy Explorer satellite (RAE‐1) is the first spacecraft designed exclusively for radio astronomical studies. It is a small, but relatively complex, observatory including two 229‐meter antennas, several radiometer systems covering a frequency range of 0.2 to 9.2 MHz, and a variety of supporting experiments such as antenna impedance probes
R. R. Weber, J. K. Alexander, R. G. Stone   +2 more
openaire   +1 more source

Ageing Characterization Under Thermal Test of a Receiver Unit for a Radio Telescope

IEEE Open Journal of Instrumentation and Measurement, 2022
The Square Kilometer Array low (SKAlow) is an outstanding project aiming at building the world’s largest and most sensitive radio telescope. The Australian Murchison Shire desert has been chosen as location for the low-frequency antennas because ...
Marcantonio Catelani, Lorenzo Ciani, Gabriele Patrizi, Roberto Singuaroli, Jader Monari, Federico Perini   +5 more
doaj   +1 more source

Open skies: the National Radio Astronomy Observatory and its impact on US radio astronomy [PDF]

, 2020
This open access book on the history of the National Radio Astronomy Observatory covers the scientific discoveries and technical innovations of late 20th century radio astronomy with particular attention to the people and institutions involved.
Kellermann, Kenneth I., Bouton, Ellen N., Bouton, Ellen N, Kellermann, Kenneth I, Brandt, Sierra S, Brandt, Sierra S.   +5 more
core   +1 more source

ULF wave effects on high frequency signal propagation through the ionosphere [PDF]

Annales Geophysicae, 2009
Variations in the total electron content (TEC) of the ionosphere alter the propagation characteristics of EM radiation for frequencies above a few megahertz (MHz).
C. L. Waters, S. P. Cox
doaj   +1 more source

Radio physics and radio astronomy

, 2021
International audiencePurpose: Review of investigations of cosmic sources radioemission scintillations due to interplanetary plasma irregularities made at the Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, from the first ...
Brazhenko, A, I, Ivantyshyn Karpenko, O, L, Lytvynenko, O, O, Zarka, P, Lesia, A, Lecacheux, Institute, Physiko-Mechanical, Kuhai, N, V, Kalinichenko, M, M, Romanchuk, O, I, Frantsuzenko, A, V, Bubnov, I, M, Yerin, S, M, Rucker, H, O, Konovalenko, O, O   +13 more
core   +1 more source

Accelerating software radio astronomy FX correlation with GPU and FPGA co-processors [PDF]

, 2010
Includes abstract.Includes bibliographical references (leaves [117]-121).This thesis attempts to accelerate compute intensive sections of a frequency domain radio astronomy correlator using dedicated co-processors.
Woods, Andrew
core   +1 more source

Electronic spectroscopy of cold ions in a radio-frequency trap [PDF]

, 2010
The low density of ions in mass spectrometers generally precludes direct absorption measurements. The spectrum of ions can nonetheless be obtained by using resonance two-color photofragmentation or multiphoton photofragmentation techniques.
Rudnev, Vitaly S.
core   +1 more source

Test-Driven Design of an Active Dual-Polarized Log-Periodic Antenna for the Square Kilometre Array

IEEE Open Journal of Antennas and Propagation, 2020
An active dual-polarized Log-Periodic antenna has been designed to meet the requirements of the low-frequency (50 - 350 MHz) radio telescope of the Square Kilometre Array (SKA).
Pietro Bolli, Lorenzo Mezzadrelli, Jader Monari, Federico Perini, Alberto Tibaldi, Giuseppe Virone, Mirko Bercigli, Lorenzo Ciorba, Paola Di Ninni, Maria Grazia Labate, Vittorio Giuseppe Loi, Andrea Mattana, Fabio Paonessa, Simone Rusticelli, Marco Schiaffino   +14 more
doaj   +1 more source

First Radio Astronomy Examination of the Low-Frequency Broadband Active Antenna Subarray

Advances in Astronomy, 2014
We present the 25-element active antenna array and its remote control in the framework of the GURT project, the Ukrainian Radio Telescope of a new age. To implement beamforming, the array is phased with the help of discrete cable delay lines in analog ...
A. A. Stanislavsky, I. N. Bubnov, A. A. Konovalenko, A. A. Gridin, V. V. Shevchenko, L. A. Stanislavsky, D. V. Mukha, A. A. Koval   +7 more
doaj   +1 more source

Ultimate precision in cosmic-ray radio detection — the SKA

EPJ Web of Conferences, 2017
As of 2023, the low-frequency part of the Square Kilometre Array will go online in Australia. It will constitute the largest and most powerful low-frequency radio-astronomical observatory to date, and will facilitate a rich science programme in astronomy
Huege Tim, Bray Justin D., Buitink Stijn, Butler David, Dallier Richard, Ekers Ron D., Enßlin Torsten, Falcke Heino, Haungs Andreas, James Clancy W., Martin Lilian, Mitra Pragati, Mulrey Katharine, Nelles Anna, Revenu Benoît, Scholten Olaf, Schröder Frank G., Tingay Steven, Winchen Tobias, Zilles Anne   +19 more
doaj   +1 more source