Excluding maneuver time periods, Figure 1 (left) shows an almost constant consistency level between AIUB and DLR with STDs of about 0.5, 0.9, and 1.0 mm in the radial, along-track, and out-of-plane components, respectively. Apart from the out-of-plane component, the comparisons between GFZ and the other agencies reveal a slightly larger variability for the radial and along-track component, e.g., about 0.24 instead of 0.09 mm variability for the along-track component, but with almost identical overall STDs. Figure 1 (right) shows a further improvement when using single-frequency data, e.g., STDs of about 0.3, 0.4, and 0.8 mm in the radial, along-track, and out-of-plane components between AIUB and DLR. When including maneuver time periods in the comparison of the solutions, a significant increase of the STD (up to a factor of two over 24 h) can be observed for the baseline difference in the radial and along-track direction.
Figure 2 show biases of about 1 mm at maximum between all agencies for dual-frequency solutions. Smallest biases of 0.1–0.2 mm occur for the radial direction. Tight relative constraints imposed on the empirical accelerations in the radial direction ensure a similar leveling for all baseline solutions. A consistent force modeling is more important to keep biases between the different solutions small than to significantly improve the STDs.