Results 51 to 60 of about 3,469 (207)
Implementation and performance analysis of real time PPP software based on GAMP
Dianzi Jishu Yingyong, 2022 Aiming at the problem that GAMP software lacks the function of real-time precise point positioning at this stage, this paper analyzes and studies the principle and process of the post precise point positioning algorithm in the software, compares the ...
Liu Ya, He Wentao, Zhang Jie
doaj +1 more source
Method and apparatus for autonomous, in-receiver prediction of GNSS ephemerides [PDF]
, 2012 Methods and apparatus for autonomous in-receiver prediction of orbit and clock states of Global Navigation Satellite Systems (GNSS) are described. Only the GNSS broadcast message is used, without need for periodic externally-communicated information ...
Bar-Sever, Yoaz E., Bertiger, William I.
core +1 more source
The Future of Time: UTC and the Leap Second
, 2011 Before atomic timekeeping, clocks were set to the skies. But starting in 1972, radio signals began broadcasting atomic seconds and leap seconds have occasionally been added to that stream of atomic seconds to keep the signals synchronized with the actual
Allen, Steve +4 more
core +1 more source
A GIVE Prediction Method in SBAS Based on GAT‐TCN
Space Weather, Volume 23, Issue 11, November 2025.Abstract A Grid Ionospheric Vertical Error (GIVE) prediction model based on GAT‐TCN is proposed in this paper. The model integrates the Graph Attention Network (GAT) with the Temporal Convolutional Network to enhance prediction accuracy while ensuring the integrity of the Satellite‐Based Augmentation System, thereby improving its availability.
Hao Zhang +8 more
wiley +1 more source
A Flexible Ephemeris Representation for GNSS and Alternative PNT Signal Sources Using B-Splines
Navigation, 2023 Most global navigation satellite systems (GNSSs) ephemeris representations require straightforward, albeit specialized algorithms to compute the transmitter position at a time of interest.
Mikaela Dobbin, Penina Axelrad
doaj +1 more source
Long term frequency stability analysis of the GPS NAVSTAR 6 Cesium clock [PDF]
, 1982 Time domain measurements, taken between the NAVSTAR 6 Spacecraft Vehicle (SV) and the Vandenberg Global Positioning System (GPS) Monitor Site, by a pseudo random noise receiver, were collected over an extended period of time and analyzed to estimate the ...
Buisson, J. +3 more
core +1 more source
Ionospheric Disturbances During the 4 December 2015, Mt. Etna Eruption
Earth and Space Science, Volume 12, Issue 10, October 2025.Abstract This study presents the detection and characterization of co‐volcanic ionospheric disturbances (CVIDs) associated with Mt. Etna's large‐scale lava fountain (Italy). Leveraging a dense and proximal GNSS network, we identify local Total Electron Content (TEC) perturbations extending up to ∼ ${\sim} $200 km south/southwest of the vent.
F. Ferrara +7 more
wiley +1 more source
Impacts of Satellite Orbit and Clock on Real-Time GPS Point and Relative Positioning
Sensors, 2017 Satellite orbit and clock corrections are always treated as known quantities in GPS positioning models. Therefore, any error in the satellite orbit and clock products will probably cause significant consequences for GPS positioning, especially for real ...
Junbo Shi +3 more
doaj +1 more source
Phoenix-XNS - A Miniature Real-Time Navigation System for LEO Satellites [PDF]
, 2006 The paper describes the development of a miniature GPS receiver with integrated real-time navigation system for orbit determination of satellites in low Earth orbit (LEO).
Gill, Eberhard, Montenbruck, Oliver
core
Real‐Time Regional Ionosphere Modeling With RFR‐Net Over China
Space Weather, Volume 23, Issue 8, August 2025.Abstract The mid‐to‐low‐latitude ionosphere, influenced by phenomena such as the Equatorial Ionization Anomaly, responds more sensitively to changes in solar activity, which negatively affect the transmission of various electromagnetic signals. Moreover, next‐generation technologies, particularly Precise Point Positioning‐Real‐Time Kinematic (PPP‐RTK),
Mengfei Sun +9 more
wiley +1 more source