Table 10 Strategies and models adopted in the GRACE-FO satellite POD procedure

Sample rate

30 s

Cutoff elevation

1°

Observation

Undifferenced ionosphere-free linear combination of code and phase measurements on GPS L1/L2

Observation weighting

A priori precision of 5 mm for SLR observations, and a priori precision of 0.3 m and 2 mm for GPS raw code and phase observations

GPS orbit and clock

Products released by WHU

Observation-specific signal bias

Products released by WHU (Geng et al., 2022)

On-board GPS antenna phase center location vector

Values provided by Save (2019)

On-board laser retroreflector array coordinate

Values provided by Save (2019)

Tropospheric delay

For SLR, corrected via Mendes and Pavlis (2004)

For LEO on-board GPS, not considered

SLR range bias

Estimated as constant for each station per day (Couhert et al., 2018)

GRACE-FO satellite attitude

Quaternion products

Earth gravity

European Improved Gravity model of the Earth by New techniques (EIGEN6C) (120 × 120) (Shako et al., 2014)

Solar radiation pressure

Macro-model

Atmospheric drag

Drag Temperature Model (DTM 94) is applied (Berger et al., 1998); Piecewise constant coefficients of atmospheric drag are estimated with an interval of 90 min

Earth radiation pressure

Not considered

Empirical acceleration

Piecewise periodical parameters in the along-track and cross-track directions are estimated with an interval of 90 min