Affine distortion of small GPS networks with large height differences |
| |
Authors: | Steffen Schön |
| |
Institution: | 1.Engineering Geodesy and Measurements Systems (EGMS),Graz University of Technology,Graz,Austria;2.Institut für Erdmessung,Leibniz-Universit?t Hannover,Hannover,Germany |
| |
Abstract: | GPS is a promising tool for real-time monitoring of deformations of slopes or large structures. However, remaining systematic
effects in GPS phase observations after double differencing and application of a priori models affect the resulting coordinates.
They complicate the proper separation of the actual deformations from pseudo-deformations induced by the systematic effects.
This paper shows that for small monitoring networks (baseline lengths <5 km) only affine distortions of the network geometry
are generated by the remaining distance dependent systematic effects, e.g. unmodelled tropospheric and ionospheric propagation
effects, or satellite orbit errors. Hence, a generic correction model is given by a three-dimensional affine transformation
involving a maximum of 12 transformation parameters. For the determination of these parameters, four high quality GPS stations
are necessary which are not affected by the actual deformations to be monitored. Based on the analysis of network geometries
of synthetic GPS networks with large height differences and considering the physics of the GPS observations it is shown, however,
that less than 12 parameters are sufficient for the computation of the corrections. The proposed 8 parameter model was applied
to the GPS monitoring network of the Gradenbach landslide. For this small network with large height differences, it was shown
that the distortions can be reduced by about 75%. |
| |
Keywords: | GPS Systematic errors Monitoring network Affine transformation |
本文献已被 SpringerLink 等数据库收录! |
|