Systematic errors of a VLBI determined TRF investigated by simulations

In this study, we investigate the influence of different analysis setup options for the processing of VLBI measurement data from 2002 until 2010 to derive the terrestrial reference frame (TRF). For estimating the consequent changes of the TRF, the simulation tool of the Vienna VLBI Software (VieVS) is used by applying different a priori models. We show that neglecting atmosphere loading causes a systematic annual scale variation of±0.3 mm, and that the application of the cubic model recommended in the most recent IERS Conventions for the mean pole introduces a scale change of −0.6mm over 8.5years. The effects of antenna thermal deformation on the TRF are±0.5 to 1mm/year in translation and±2 mm/year in scale. No systematic effects are found for the different troposphere mapping functions tested. Besides systematic, annual, and episodic impacts on the coordinates, we focus on possible changes in the scale of the reference frames.