Results 21 to 30 of about 2,143 (164)
Universe, 2023 The discovery of diffuse radio emission in galaxy clusters proved the existence of energetic cosmic-ray electrons and cosmic magnetic fields on Mpc-scales in the Universe.
Denis Wittor
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Low Frequency Radio Astronomy from Earth Orbit [PDF]
International Astronomical Union Colloquium, 1990 AbstractLow frequency radio astronomy for the purpose of this discussion is defined as frequencies ≲100 MHz. Since the technology is fairly simple at these frequencies and even Jansky’s original observations were made at 20.5 MHz, there have been many years of research at these wavelengths.
Kurt W. Weiler, Namir E. Kassim
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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 +5 more
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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
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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 +14 more
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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 +7 more
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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 +2 more
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A Low-Insertion Loss Cryogenic Edge-Mode Isolator With 18 GHz Bandwidth
IEEE Journal of Microwaves, 2023 Cryogenic isolators play an important role in low-noise receiver systems widely employed in millimeter and submillimeter telescopes. To enable a significantly wider Intermediate Frequency (IF) bandwidth, there is strong demand for a wideband, low-loss ...
Lingzhen Zeng +2 more
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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 +19 more
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Electromagnetic Analysis and Experimental Validation of the LOFAR Radiation Patterns
International Journal of Antennas and Propagation, 2019 Low-frequency (
Paola Di Ninni +5 more
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