000196295 001__ 196295
000196295 003__ CZ-ZdVUG
000196295 005__ 20220602113230.0
000196295 040__ $$aABC039$$bcze
000196295 1001_ $$aDouša, Jan
000196295 24510 $$aA flexible strategy for handling the datum and initial bias in real-time GNSS satellite clock estimation
000196295 300__ $$a11 stran
000196295 5203_ $$aInvestigations have been focused on improving the precision of real-time GNSS satellite clock corrections. There is a little literature analyzing the characteristics and impacts of the clock datum and initial clock biases (ICBs). We illustrated the clock anomaly caused by the two factors and proposed a new strategy flexible for global and regional clock estimation based on the mixed-difference observation method. First, we analyzed the clock datum of the final and real-time clocks. Results show that the variation in the clock datum can be up to 500 ns per day depending on the datum definition strategy. The variations can lead to large inconsistencies in the datum for the re-convergence of estimated satellite clocks when using the mixed-difference clock estimation method. To resolve the problem, we propose a new method for the epoch-by-epoch datum definition, which can screen out any outliers in broadcast ephemeris in real time, and particularly suitable for the real-time clock estimation. Second, we analyzed ICB jumps in real-time clock corrections, which can degrade the accuracy of precise point positioning. We propose a short-term prediction of clock corrections for bridging ICBs with the precision better than 0.1 ns for stable satellite clocks within a gap of 1–3 min. The prediction can decrease the magnitude of ICB jumps and thus improve a user solution. Considering the prediction of clocks, high precision cannot be guaranteed for all conditions, we thus recommend broadcasting a discontinuity flag for real-time service, so the re-convergence of ICB can be identified by users for resetting carrier-phase ambiguities.
000196295 655_4 $$ačlánek v časopise
000196295 7001_ $$aVáclavovic, Pavel
000196295 7001_ $$aZhao, Lewen
000196295 7001_ $$aYe, Shirong
000196295 7730_ $$92020$$dSpolková republika Německo,2020.$$g94. (1), 11 s.$$tJournal of Geodesy$$x0949-7714
000196295 8564_ $$uhttps://link.springer.com/article/10.1007/s00190-019-01328-9
000196295 85642 $$ahttps://www.isvavai.cz/riv?s=rozsirene-vyhledavani&ss=detail&n=0&h=RIV%2F00025615%3A_____%2F20%3AN0000037%21RIV21-MSM-00025615
000196295 910__ $$aABC039
000196295 980__ $$aclanky_vugtk
000196295 985__ $$adousa
000196295 985__ $$ariv
000196295 985__ $$autvar24
000196295 985__ $$avaclavovic