Results 41 to 50 of about 14,980 (205)
The Short-Arc Precise Orbit Determination of GEO Satellites Using VLBI and Transfer Ranging
Remote Sensing, 2022 It is important for a geostationary Earth orbit (GEO) satellite to rapidly recover its orbit after a maneuver with short-arc precise orbit determination (POD).
Kai Nan +5 more
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Earth, Planets and Space, 2023 VLBI simulation studies are carried out to investigate the impact of any proposed station or strategy on the geodetic parameters, such as Earth Orientation Parameters (EOP) and Terrestrial Reference Frame (TRF). In general, such studies are performed for
Sujata Dhar +5 more
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High-fidelity wideband VLBI polarimetry
, 2023 We will discuss about wideband and multiband VLBI observations taken with linear-polarization feeds (the simplest hardware polarimetry for wide bands), and how these observations can be calibrated and fringe-fitted with special software, in order to ...
Martí-Vidal, Iván
core +1 more source
International Astronomical Union Colloquium, 1990 AbstractVLBI observations using a satellite in earth orbit and ground antennas in Japan and Australia were conducted in 1986, 1987, and 1988. Sources were detected on space-ground baselines at both observing frequencies: 2.3 and 15 GHz. The coherence on space-ground baselines for 340 s was 90% at 2.3 GHz and 76% at 15 GHz.
openaire +1 more source
Decoherence in LOFAR-VLBI beamforming [PDF]
Astronomy & Astrophysics, 2020 We show that the use of a superstation (a phased array created using multiple stations of an interferometric array) created in post-processing for LOFAR-VLBI observations introduces a direction-dependent loss of signal in the image. We show this effect using simulations and real data.
Bonnassieux E. +3 more
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A Study on the Development of Playback Control Software for Mark5B VSI System [PDF]
Journal of Astronomy and Space Sciences, 2010 We developed the playback control software for a high-speed playback system which is a component of the Korea-Japan Joint VLBI Correlator (KJJVC). The Mark5B system, which is a recorder and playback system used in the Korean VLBI Network (KVN), has two
S. J. Oh +5 more
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Software and Techniques for VLBI Data Processing and Analysis
Universe, 2022 Very-long-baseline interferometry (VLBI) is a challenging observational technique, which requires in-depth knowledge about radio telescope instrumentation, interferometry, and the handling of noisy data.
Michael Janssen +2 more
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Ground Based VLBI Facilities - the European and Global VLBI Network [PDF]
, 2004 11 pages, 5 figures, lecture presented at the NATA ASI VLBI School, Oct 2001. To be published in "The Role of VLBI in Astrophysics, Astrometry and Geodesy", ed. F. Mantovani.
openaire +2 more sources
Preparation of the VIRAC Radio Telescope RT-32 for e-VLBI Observations
Open Astronomy, 2013 A fully steerable parabolic antenna RT-32 with the mirror diameter 32 m owned by the Ventspils International Radio Astronomy Centre (VIRAC) is available for fundamental and applied research in radio astronomy.
Skirmante K. +3 more
doaj +1 more source
Astrometric Apparent Motion of High-redshift Radio Sources
The Astronomical Journal, 2023 Radio-loud quasars at high redshift ( z ≥ 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position.
Oleg Titov +12 more
doaj +1 more source