Results 131 to 140 of about 1,544 (147)
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An improved method for real-time PPP timing and time transfer with broadcast ephemerides
Measurement Science and Technology, 2022Abstract Due to the problem of network communication, it is difficult to ensure the reliability of real-time precise point positioning (PPP) timing/time transfer with real-time precise products. With the continued reduction in the signal-in-space range error, the performance and feasibility of GPS and Galileo PPP ...
Yulong Ge, Xinyun Cao, Fei Shen
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Accuracy evaluation of Doresa and Milena Galileo satellites broadcast ephemerides
2018 IEEE International Workshop on Metrology for the Sea; Learning to Measure Sea Health Parameters (MetroSea), 2018On 22 August 2014 Doresa and Milena Galileo satellites were launched in wrong orbit. In November 2014 European space agency started a salvaged mission to make two satellites usable. On 5 August 2016 these two satellites started broadcasting ephemerides in navigation message for testing purposes.
Umberto Robustelli +2 more
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Precise On-Board Navigation of LEO Satellites with GNSS Broadcast Ephemerides
Proceedings of the Satellite Division's International Technical Meeting, 2020The availability of orbit information with high precision and low latency is a key requirement for many Earthobservation missions, predominantly in the field of radio occultation. Traditionally, precise orbit determination solutions of low-Earth orbit (LEO) satellites are done offline on the ground after dwonloading GNSS measurements and required ...
André Hauschild, Oliver Montenbruck
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International Journal of Satellite Communications and Networking, 1994
AbstractFrequency stability analysis of on‐orbit Navstar clocks is performed by the Naval Research Laboratory using both the broadcast and the precise post‐processed ephemerides. The phase offset between the Navstar clock and the reference clock is computed from pseudorange measurements obtained by dual‐frequency GPS receivers at the five GPS monitor ...
Thomas B. McCaskill +3 more
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AbstractFrequency stability analysis of on‐orbit Navstar clocks is performed by the Naval Research Laboratory using both the broadcast and the precise post‐processed ephemerides. The phase offset between the Navstar clock and the reference clock is computed from pseudorange measurements obtained by dual‐frequency GPS receivers at the five GPS monitor ...
Thomas B. McCaskill +3 more
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BDS-3 and GPS/Galileo integrated PPP using broadcast ephemerides
GPS Solutions, 2022Na Wei, Qile Zhao
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Broadcast vs. precise GPS ephemerides: a historical perspective
GPS Solutions, 2003David L. M. Warren, John F. Raquet
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GPS positioning with broadcast and precise ephemerides
SICE '95. Proceedings of the 34th SICE Annual Conference. International Session Papers, 2002The precise ephemeris and space vehicle clock corrections computed routinely by the International GPS Service for Geodynamics (IGS) under the International Association of Geodesy (IAG) is accurate to less than submeter. Since the precise orbit/clock is free from selective availability (SA) errors, accurate point positioning and orbit determination can ...
M. Murata, M. Harigae, T. Tsujii
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Broadcast versus precise ephemerides: a multi-GNSS perspective
GPS Solutions, 2014A consistent analysis of signal-in-space ranging errors (SISREs) is presented for all current satellite navigation systems, considering both global average values and worst-user-location statistics. The analysis is based on 1 year of broadcast ephemeris messages of the Global Positioning System (GPS), GLONASS, Galileo, BeiDou and QZSS collected with a ...
Montenbruck, Oliver +2 more
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