Results 141 to 150 of about 779 (166)
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Ephemeris and Timing Error Disambiguation Enabling Precise LEO PNT
IEEE Transactions on Aerospace and Electronic SystemsZaher Kassas, Joe Saroufim
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Comparing the Timescales in Public, Precise Ephemeris Products
The Precise Time and Time Interval Systems and Applications Meeting, 2021Given the importance of GPS multiple organizations regularly process satellite position and clock data to create publicly available, precise ephemeris products. Underlying each product is a timescale that describes the satellite clock biases. This work uses what amounts to a common view time-transfer method on three years’ worth of data to compare the ...
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Precise Seasat ephemeris from laser and altimeter data
Advances in Space Research, 1985Abstract The determination of a precise Seasat ephemeris has required improvements in the modeling of the gravitational and nongravitational forces acting on the satellite. Because laser range data were used as the primary ground-based tracking measurement, the limited data distribution in July and August, 1978, necessitated the use of other data to ...
B.E. Schutz, B.D. Tapley, C.K. Shum
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High-precision analytical representation of lunar ephemeris
Doklady Physics, 2007zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Research on BDS/GPS High-precision Long-period Ephemeris Extrapolation Technology
2021 IEEE 4th International Conference on Electronic Information and Communication Technology (ICEICT), 2021In order to improve the surface satellite positioning efficiency of the underwater vehicle, a simple and efficient high-precision long-period ephemeris extrapolation technology method is proposed to solve the problem of too long time for the first satellite positioning of the submarine after a long underwater navigation.
Jun Fu, Teng Lv
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Precise Timings of Galilean Satellite Eclipses and Assessment of the E-3 Ephemeris
Icarus, 1994Abstract Astrometric positions for the Galilean satellites are derived from high-precision timings of their jovian eclipses observed with CCD cameras between 1990 to 1993, and the positions are compared to Lieske's E-3 ephemeris. The root-mean-square (rms) ephemeris residuals for Io and Callisto were only 80 and 89 km, respectively; the rms residuals
Anthony Mallama +5 more
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Precision Analysis of CNAV Broadcast Ephemeris and Its Impact on the User Positioning
2017GPS broadcast ephemeris error is an important factor affecting the real-time positioning accuracy. Since April 2014, the IGS provided two new broadcast ephemeris products, namely LNAV (Legacy Navigation Message) and CNAV (Civil Navigation Message). Compared with LNAV, CNAV was broadcasted only on Block IIR-M and IIF satellites.
Ahao Wang, Junping Chen, Jiexian Wang
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Chinese Astronomy and Astrophysics, 2009
Abstract The satellite-borne GPS receivers dedicated to precise orbit determination are now being carried by more and more low earth orbit (LEO) satellites and the satellite-borne GPS has become one of the main means for the precise orbit determination of low earth orbit satellites.
Dong-ju, P., Bin, W.
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Abstract The satellite-borne GPS receivers dedicated to precise orbit determination are now being carried by more and more low earth orbit (LEO) satellites and the satellite-borne GPS has become one of the main means for the precise orbit determination of low earth orbit satellites.
Dong-ju, P., Bin, W.
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Journal of Geophysical Research: Solid Earth, 1993
Perturbations of Earth rotation are currently observed as time variations of universal time UT1‐UTC and as changes in the terrestrial and the celestial orientation of the axis of the celestial ephemeris pole (CEP) as expressed by five Earth orientation parameters (EOP).
Aleksander Brzeziński, Nicole Capitaine
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Perturbations of Earth rotation are currently observed as time variations of universal time UT1‐UTC and as changes in the terrestrial and the celestial orientation of the axis of the celestial ephemeris pole (CEP) as expressed by five Earth orientation parameters (EOP).
Aleksander Brzeziński, Nicole Capitaine
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2012 IEEE First AESS European Conference on Satellite Telecommunications (ESTEL), 2012
In the frame of a simulation facility developed for the Italian Space Agency (ASI) and the Air Navigation Services company (ENAV), Telespazio handled the problem of generating the Precision Ephemeris (PE) parameter sets for a simulated Galileo constellation.
R. Marson, S. Lagrasta, F. Malvolti
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In the frame of a simulation facility developed for the Italian Space Agency (ASI) and the Air Navigation Services company (ENAV), Telespazio handled the problem of generating the Precision Ephemeris (PE) parameter sets for a simulated Galileo constellation.
R. Marson, S. Lagrasta, F. Malvolti
openaire +1 more source