Results 11 to 20 of about 43,155 (284)
An optimal design of the broadcast ephemeris for LEO navigation augmentation systems
Geo-spatial Information Science, 2022 As the deployment of large Low Earth Orbiters (LEO) communication constellations, navigation from the LEO satellites becomes an emerging opportunity to enhance the existing satellite navigation systems.
Xueli Guo +5 more
doaj +2 more sources
Satellite Navigation, 2023 Previous studies have not evaluated the systematic errors implied in the third generation of BeiDou-3 Navigation Satellite System (BDS-3) broadcast ephemeris.
Min Li +4 more
doaj +2 more sources
TESS Timings of 31 Hot Jupiters with Ephemeris Uncertainties [PDF]
The Astrophysical Journal Supplement Series, 2023 A precise transit ephemeris serves as the premise for follow-up exoplanet observations. We compare TESS Object of Interest (TOI) transit timings of 262 hot Jupiters with the archival ephemeris and find 31 of them having TOI timing offsets, among which ...
Su-Su Shan +10 more
doaj +2 more sources
Remote Sensing, 2022 Since BeiDou Navigation Satellite System (BDS) and Japan’s Quasi-Zenith Satellite System (QZSS) have more visible satellites in the Asia-Pacific region, and navigation satellites of Global Positioning System (GPS), Galileo satellite navigation system ...
Mengyuan Li +4 more
doaj +2 more sources
Study on Optimal Broadcast Ephemeris Parameters for GEO/IGSO Navigation Satellites
Sensors, 2020 This paper proposes new sets of suitable broadcast ephemeris parameters for geosynchronous (GEO) and inclined geosynchronous (IGSO) navigation satellites (NSs).
Jin Haeng Choi +3 more
doaj +2 more sources
Broadcast Ephemeris with Centimetric Accuracy: Test Results for GPS, Galileo, Beidou and Glonass
Remote Sensing, 2021 Here we test the capability of the Broadcast Ephemeris Message, in both its GPS-like (Keplerian ellipse with secular and periodic perturbations) and Glonass-like (numerical integration of a 9D state vector) formats, to reproduce a corresponding precise ...
Alessandro Caporali, Joaquin Zurutuza
doaj +2 more sources
Improving BDS broadcast ephemeris accuracy using ground-satellite-link observations
Satellite Navigation, 2022 The BeiDou Navigation Satellite System (BDS) employs a hybrid constellation including GEO (Geosynchronous Earth Orbit), IGSO (Inclined Geosynchronous Orbit), and MEO (Medium Earth Orbit) satellites, where the GEO and IGSO satellites are critical to ...
Junping Chen +4 more
doaj +2 more sources
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 +2 more sources
La2010: A new orbital solution for the long term motion of the Earth [PDF]
, 2011 We present here a new solution for the astronomical computation of the orbital motion of the Earth spanning from 0 to -250 Myr. The main improvement with respect to the previous numerical solution La2004 (Laskar et al.
A. Fienga +50 more
core +8 more sources
Prediction of Communication Outage Period between Satellite and Earth station Due to Sun Interference [PDF]
Journal of Astronomy and Space Sciences, 2010 We developed a computer program to predict solar interference period. To calculate Sun‘s position, we used DE406 ephemerides and Earth ellipsoid model. The Sun‘s position error is smaller than 10arcsec. For the verification of the calculation, we used
Yongjun Song +3 more
doaj +1 more source