Results 151 to 160 of about 163,832 (185)
Retrieval of refractivity fields from GNSS tropospheric delays: theoretical and data-based evaluation of collocation methods and comparisons with GNSS tomography. [PDF]
J GeodShehaj E +3 more
europepmc +1 more source
Broadcast ephemerides for LEO augmentation satellites based on nonsingular elements
GPS Solutions, 2021 Low earth orbit (LEO) satellite constellations have the potential to augment global navigation satellite system services. Among the ongoing tasks of LEO-based navigation, providing broadcast ephemerides that satisfy the accuracy requirement for positioning, navigation, and timing is one of the most critical prerequisites.
Lingdong Meng +3 more
semanticscholar +3 more sources
An improved method for real-time PPP timing and time transfer with broadcast ephemerides
Measurement Science and Technology, 2022 Abstract 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 +5 more
semanticscholar +3 more sources
Precise On-Board Navigation of LEO Satellites with GNSS Broadcast Ephemerides
ION GNSS+, The International Technical Meeting of the Satellite Division of The Institute of Navigation, 2020 The 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
semanticscholar +4 more sources
Broadcast versus precise ephemerides: a multi-GNSS perspective
GPS Solutions, 2014 A 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 ...
Oliver Montenbruck +2 more
semanticscholar +4 more sources
Accuracy Assessment of Broadcast Ephemerides for Quasi-Zenith Satellite System
, 2018 In this paper, we presented a method for assessing the broadcast ephemerides accuracy of QZSS by comparing the measured broadcast ephemerides with precise orbit and clock products provided by MGEX. By using this method, we carried out assessment of broadcast ephemerides for QZS-1 satellite and also compared the results with that of GPS system during ...
Xuying Ma +4 more
semanticscholar +3 more sources
GPS positioning with broadcast and precise ephemerides
SICE '95. Proceedings of the 34th SICE Annual Conference. International Session Papers, 2002 The 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 ...
Masaya Murata +2 more
semanticscholar +3 more sources
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), 2018 On 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
semanticscholar +6 more sources
BDS-3 and GPS/Galileo integrated PPP using broadcast ephemerides
GPS Solutions, 2022 Guo Chen +4 more
semanticscholar +3 more sources