000196398 001__ 196398
000196398 003__ CZ-ZdVUG
000196398 005__ 20220607110841.0
000196398 041__ $$aeng
000196398 040__ $$aABC039$$bcze
000196398 1001_ $$aDouša, Jan
000196398 24510 $$aAccuracy Evaluation of Ionospheric Delay from Multi-Scale Reference Networks and Its Augmentation to PPP during Low Solar Activity
000196398 300__ $$a18 stran
000196398 5203_ $$aThe Precise Point Positioning (PPP) with fast integer ambiguity resolution (PPP-RTK) is feasible only if the solution is augmented with precise ionospheric parameters. The vertical ionospheric delays together with the receiver hardware biases, are estimated simultaneously based on the uncombined PPP model. The performance of the ionospheric delays was evaluated and applied in the PPP-RTK demonstration during the low solar activity period. The processing was supported by precise products provided by Deutsches GeoForschungsZentrum Potsdam (GFZ) and also by real-time products provided by the National Centre for Space Studies (CNES). Since GFZ provides only precise orbits and clocks, other products needed for ambiguity resolution, such as phase biases, were estimated at the Geodetic Observatory Pecny (GOP). When ambiguity parameters were resolved as integer values in the GPS-only solution, the initial convergence period was reduced from 30 and 20 min to 24 and 13 min when using CNES and GFZ/GOP products, respectively. The accuracy of ionospheric delays derived from the ambiguity fixed PPP, and the CODE global ionosphere map were then assessed. Comparison of ambiguity fixed ionospheric delay obtained at two collocated stations indicated the accuracy of 0.15 TECU for different scenarios with more than 60% improvement compared to the ambiguity float PPP. However, a daily periodic variation can be observed from the multi-day short-baseline ionospheric residuals. The accuracy of the interpolated ionospheric delay from global maps revealed a dependency on the location of the stations, ranging from 1 to 3 TECU. Precise ionospheric delays derived from the EUREF permanent network with an inter-station distance larger than 73 km were selected for ionospheric modeling at the user location. Results indicated that the PPP ambiguity resolution could be achieved within three minutes. After enlarging the inter-station distance to 209 km, ambiguity resolution could also be achieved within several minutes.
000196398 655_4 $$ačlánek v odborném časopise
000196398 7001_ $$aVáclavovic, Pavel
000196398 7001_ $$aZhao, Lewen
000196398 7001_ $$ahttps://www.mdpi.com/2220-9964/10/8/516
000196398 7730_ $$92021$$dAmsterdan:Elsevier,2021.$$g10. (8), 18 s.$$tISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION$$x2220-9964
000196398 85642 $$ahttps://www.isvavai.cz/riv?s=rozsirene-vyhledavani&ss=detail&n=0&h=RIV%2F00025615%3A_____%2F21%3AN0000035%21RIV22-MSM-00025615
000196398 910__ $$aABC039
000196398 980__ $$aclanky_vugtk
000196398 985__ $$adousa
000196398 985__ $$ariv
000196398 985__ $$autvar24
000196398 985__ $$avaclavovic