Table 2 Details for processing GNSS observations using GAPS Desktop V6.0.0
Parameter | Input |
|---|---|
Satellite elevation cut-off angle | 10° |
Observation weighting | 1/ sin ε |
Ocean loading model | Not applicable |
APL time series | Non-tidal, provided by Goddard Very Long Baseline Interferometry (VLBI) group available at http://gemini.gsfc.nasa.gov/aplo |
Earth model | Spherically Symmetric Non-Rotating Elastic Isotropic (SNREI) Earth model, adopting Preliminary Reference Earth Model (PREM) |
A priori tropospheric delay model | Vienna Mapping Functions 1 (VMF1) |
Atmospheric pressure fields | National Center for Environmental Protection (NCEP) Resolution of 2.5° × 2.5°, at 4 times daily |
Error sources modelled | Solid earth tides, ocean tidal loading, satellite antenna phase wind-up, satellite/receiver antenna offsets and satellite/receiver phase centre variations |
Estimated parameters | Residual zenith delay (\(\updelta T\)), receiver position (\(X,Y,Z\)), receiver clock bias (\(\text{d}t\)) and one carrier phase ambiguity per satellite \(N_{i}\) |