Bibliografie VÚGTK
Sensitivity of GNSS tropospheric gradients to processing options
Douša, Jan ;
Václavovic, Pavel
Source: Annales Geophysicae
: 37. (3), s. 429-446
ISSN: 0992-7689
Publication type: článek v časopise
Extent18 stran
10.5194/angeo-37-429-2019
Link: https://www.ann-geophys.net/37/429/2019/
Annotation:
An 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.
Citation: DOUŠA, Jan, Pavel VÁCLAVOVIC, Kyriakos BALIDAKIS, Galina DICK, Michal KAČMAŘÍK, Jens WICKERT a Florian ZUS. Sensitivity of GNSS tropospheric gradients to processing options. Annales Geophysicae [online]. Spolková republika Německo, 2019, 37(3), 429-446 [cit. 2020-12-08]. ISSN 0992-7689. Dostupné z: doi:10.5194/angeo-37-429-2019
The record appears in these collections:
Focus on VÚGTK > VÚGTK Departments > Geodesy and Geodynamics
Focus on VÚGTK > Researchers > Pavel Václavovic
Focus on VÚGTK > Researchers > Jan Douša
Documents of VÚGTK > Articles VÚGTK
Focus on VÚGTK > RIV
Record created 2020-09-16, last modified 2021-06-28