Results 51 to 60 of about 166,231 (222)
Signal in Space Error and Ephemeris Validity Time Evaluation of Milena and Doresa Galileo Satellites
Sensors, 2019 In August 2016, Milena (E14) and Doresa (E18) satellites started to broadcast ephemeris in navigation message for testing purposes. If these satellites could be used, an improvement in the position accuracy would be achieved.
Umberto Robustelli +2 more
doaj +1 more source
Attitude Determination from Single-Antenna Carrier-Phase Measurements
, 2002 A model of carrier phase measurement (as carried out by a satellite navigation receiver) is formulated based on electromagnetic theory. The model shows that the phase of the open-circuit voltage induced in the receiver antenna with respect to a local ...
Bohnert J. I. +7 more
core +1 more source
NavigationPlans to establish a satellite network around the Moon to support communication, position, navigation, and timing services are rapidly evolving. Satellites that are part of this system broadcast their ephemeris as finite parameters to lunar users for ...
Marta Cortinovis +2 more
doaj +1 more source
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
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
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
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
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
Ionospheric Delays Compensation for On-The-Fly Integer Ambiguity Resolution in Long Baseline LEO Formations [PDF]
, 2014 This paper deals with the real-time onboard accurate relative positioning by Carrier-phase Differential GPS (CDGPS) of LEO formations with baselines of hundreds of kilometers.
Tancredi, Urbano
core +1 more source
The Benefit of Space Clocks for the Deep Space Network
Radio Science, Volume 60, Issue 8, August 2025.Abstract Ground‐based atomic clocks have been the foundation of the Deep Space Network's (DSN's) ability to provide high‐precision tracking to deep space users for navigation and radio science since its inception in the mid‐1960s. This paper describes the development of space clocks that could aid the DSN and the solar system exploration enterprise ...
T. Ely, E. Burt, K. Cheung, R. Tjoelker
wiley +1 more source