Results 21 to 30 of about 854 (181)
Global Geodetic Observing System 2015–2018 [PDF]
Geodesy and Cartography, 2019 Global Geodetic Observing System (GGOS) was established in 2003 by the International Association of Geodesy (IAG) with the main goal to deepen understanding of the dynamic Earth system by quantifying human-induced Earth’s changes in space and time.
Krzysztof Sośnica, Jarosław Bosy
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Precise VLBI/GNSS ties with micro-VLBI
, 2023 We present here a concept of measuring local ties between collocated GNSS and VLBI stations using the microwave technique that effectively transforms a GNSS receiver to an element of a VLBI network. This is achieved by modifying the signal chain that allows to transfer voltage of the GNSS antenna to a digitizer via a coaxial cable.
Petrov, Leonid +5 more
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Geodetic VLBI Analysis at the National Geographic Institute of Spain
Proceedings, 2019 National Geographic Institute of Spain has a strong background concerning technical aspects of geodetic VLBI. As a step forward in this field, a VLBI analysis team has been set up and tests with different software packages have been carried out.
Víctor Puente +3 more
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Data Handling within the International VLBI Service
Data Science Journal, 2013 The International VLBI Service for Geodesy and Astrometry (IVS) is a globally operating service that coordinates and performs Very Long Baseline Interferometry (VLBI) activities through its constituent components.
Dirk Behrend
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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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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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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.
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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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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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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
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