Long-term consistency of multi-technique terrestrial reference frames, a spectral approach

Paper in proceeding, 2007

Analysing time series of space-geodetic station coordinates, we show that VLBI, SLR and DORIS station motions have a white noise error spectrum, while the majority of GPS station motion have a flicker noise error spectrum. In the latter case, discontinuities in the series do not account for this spectrum. Atmospheric loading has a white noise spectrum, at a much lower level than geodetic measurement errors in the long term. The series of transformation parameters derived for the GPS colocation sub-networks with VLBI, SLR and DORIS have very close spectral characteristics, reaching the 1 mm stability level at one-year interval in a white noise context.