Page - 112 - in Contributions to GRACE Gravity Field Recovery - Improvements in Dynamic Orbit Integration, Stochastic Modelling of the Antenna Offset Correction, and Co-Estimation of Satellite Orientations

0.1 1 10 100 Frequency [mHz] 10−7 10−6 10−5 Oldmodel Incl. AOC (a) Estimated PSDs for December 2005. 0.1 1 10 100 Frequency [mHz] 10−7 10−6 10−5 Oldmodel Incl. AOC (b) Estimated PSDs for April 2008. Figure 8.8: Estimated stationary noise PSD, without considering full AOC covariance matrices (in brown) and when taking them into account (in blue). (a) shows the PSDs for a month containing “bad” data with large opening angles, (b) shows the PSDs for a “good” month without such anomalies. The shaded area spans from 3.3mHz to 20mHz and indicates the band where a strong influence of non-stationary errors due to orientation uncertainty is expected. Chapter8 Star Camera Observations and Uncertainties112