000196079 001__ 196079
000196079 003__ CZ-ZdVUG
000196079 005__ 20210628122559.0
000196079 041__ $$aeng
000196079 040__ $$aABC039$$bcze
000196079 1001_ $$aDouša, Jan
000196079 24510 $$aSensitivity of GNSS tropospheric gradients to processing options
000196079 300__ $$a18 stran
000196079 500__ $$a10.5194/angeo-37-429-2019
000196079 5203_ $$aAn analysis of processing settings impacts on estimated tropospheric gradients is presented. The study is based on the benchmark data set collected within the COST GNSS4SWEC action with observations from 430 Global Navigation Satellite Systems (GNSS) reference stations in central Europe for May and June 2013. Tropospheric gradients were estimated in eight different variants of GNSS data processing using precise point positioning (PPP) with the G-Nut/Tefnut software. The impacts of the gradient mapping function, elevation cut-off angle, GNSS constellation, observation elevation-dependent weighting and real-time versus post-processing mode were assessed by comparing the variants by each to other and by evaluating them with respect to tropospheric gradients derived from two numerical weather models (NWMs). Tropospheric gradients estimated in post-processing GNSS solutions using final products were in good agreement with NWM outputs. The quality of high-resolution gradients estimated in (near-)real-time PPP analysis still remains a challenging task due to the quality of the real-time orbit and clock corrections. Comparisons of GNSS and NWM gradients suggest the 3 degrees elevation angle cut-off and GPS+GLONASS constellation for obtaining optimal gradient estimates provided precise models for antenna-phase centre offsets and variations, and tropospheric mapping functions are applied for low-elevation observations. Finally, systematic errors can affect the gradient components solely due to the use of different gradient mapping functions, and still depending on observation elevation-dependent weighting. A latitudinal tilting of the troposphere in a global scale causes a systematic difference of up to 0.3 mm in the north-gradient component, while large local gradients, usually pointing in a direction of increasing humidity, can cause differences of up to 1.0 mm (or even more in extreme cases) in any component depending on the actual direction of the gradient. Although the Bar-Sever gradient mapping function provided slightly better results in some aspects, it is not possible to give any strong recommendation on the gradient mapping function selection.
000196079 655_4 $$ačlánek v časopise
000196079 7001_ $$aVáclavovic, Pavel
000196079 7730_ $$92019$$dSpolková republika Německo,2019.$$g37. (3), s. 429-446$$tAnnales Geophysicae$$x0992-7689
000196079 8564_ $$uhttps://www.ann-geophys.net/37/429/2019/
000196079 85642 $$ahttps://www.rvvi.cz/riv?s=rozsirene-vyhledavani&ss=detail&n=0&h=RIV%2F00025615%3A_____%2F19%3AN0000058%21RIV20-MSM-00025615
000196079 910__ $$aABC039
000196079 980__ $$aclanky_vugtk
000196079 985__ $$adousa
000196079 985__ $$ariv
000196079 985__ $$autvar24
000196079 985__ $$avaclavovic