For the whole data set the daily solutions were computed using standard Bernese processing engine (BPE) script for PPP adopted for data from LGSN. Subsequently the daily solutions were combined using ADDNEQ2.
When using relative method, the coordinates and velocities of LGSN points were determined in relation to the closest IGS points Figure 3).
For the first time the absolute method of precise point positioning was used within the LGSN and thanks to the quality of used IGS products provided interesting results unaffected by the relations to the reference points.
All the data obtained at > 6 hours observation intervals within the Czech part of LGSN were reprocessed using the Bernese software ver.
In Table 1 the results of baseline changes evaluation between some points of LGSN over the period 1997-2011 are shown as velocity estimations in mm/year.
It has showed up that within the LGSN the compression trends are appearing for most of the points located north, south or west of the point VYHL, while the extensions are indicating for points mutually oriented in W-E direction.
On a local scale, as mentioned above, within the LGSN the trend exceptions are only the mutual movements between points SCZE and TVDR which have reversible (extension) character contrary to the compression trends between the surrounding points.