Results 31 to 40 of about 753,460 (195)
Galileo Single Point Positioning Assessment Including FOC Satellites in Eccentric Orbits
Remote Sensing, 2019 On August 2016, the Milena (E14) and Doresa (E18) satellites started to broadcast ephemeris in navigation message for testing purposes. As the Galileo constellation is not yet complete. It is very important to have two more satellites available since the
Umberto Robustelli, Giovanni Pugliano
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Numerical Planetary and Lunar Ephemerides: Present Status, Precision and Accuracies [PDF]
Symposium - International Astronomical Union, 1986 The Ephemeris Development Program has been in existence for nearly 20 years at JPL, providing high precision present-day knowledge of the positions of the moon and major planets. The resultant ephemerides are used extensively in the navigation of spacecraft and in the reduction of astrometric observations. They also provide a key element in the testing
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Remote Sensing, 2022 In GNSS-based navigation onboard Low Earth Orbit (LEO) satellites, typical accuracy requirements are 10 cm and 0.1 mm/s for 3D position and velocity, respectively.
Francesco Darugna +4 more
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Izračun položaja GPS-satelita iz podatkov preciznih efimerid : GPS-orbit computation from precise ephemeris data [PDF]
Geodetski Vestnik, 2005 The article describes the theoretical point of view of the GPS precise ephemerides application that should be used in most precise GPS processing. Regarding broadcast, precise ephemerides allow us to achieve a much better accuracy of the final GPS ...
Bojan Stopar +1 more
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Izračun položaja GPS-satelita iz podatkov oddanih efemerid : GPS-Orbit Computation from Broadcast Ephemeris Data [PDF]
Geodetski Vestnik, 2004 The article describes the theoretical point of view of the GPS-broadcast ephemerides application. Beside the raw GPS observations, any kind of GPS ephemerides represents indispensable data in the GPS processing engine.
Bojan Stopar +1 more
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Multi-GNSS Combined Orbit and Clock Solutions at iGMAS
Sensors, 2022 Global navigation services from the quad-constellation of GPS, GLONASS, BDS, and Galileo are now available. The international GNSS monitoring and assessment system (iGMAS) aims to evaluate the navigation performance of the current quad systems under a ...
Wei Zhou +5 more
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Extended Geometry and Probability Model for GNSS+ Constellation Performance Evaluation
Remote Sensing, 2020 We proposed an extended geometry and probability model (EGAPM) to analyze the performance of various kinds of (Global Navigation Satellite System) GNSS+ constellation design scenarios in terms of satellite visibility and dilution of precision (DOP) et al.
Lingdong Meng +4 more
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Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACTLow-mass X-ray binaries have long been theorized as potential sources of continuous gravitational-wave radiation, yet there is no observational evidence from recent LIGO/Virgo observing runs. Even for the theoretically ‘loudest’ source, Sco X-1, the upper limit on gravitational-wave strain has been pushed ever lower.
T L Killestein +5 more
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A Short-Term Forecasting Method of Inter-Frequency Clock Bias for GPS Block IIF Satellites
Remote Sensing, 2022 The time-varying biases within carrier phase observations are integrated into satellite clock offset parameters for precise clock estimation. Consequently, when the precise satellite clock bias is applied to the third frequency observation for precise ...
Caiya Yue +5 more
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International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT Low Earth Orbit (LEO) satellite constellations offer unprecedented opportunities for global broadband connectivity but pose significant beamforming challenges due to rapid platform motion and stringent onboard hardware constraints. Fully digital architectures, while optimal in theory, remain impractical for satellite payloads, motivating ...
Mohammad Momani +2 more
wiley +1 more source