Analysis of GPS, VLBI and DORIS input time series for ITRF2014

In this work we have compared the Up component time series reprocessed in view of the new ITRF2014. The solutions that we have considered are the combinations of individual submissions of the Operational Analysis Centers (ACs) as o- cial IVS, IGS and IDS products.We have modelled time series as discrete-time Marcov processes, we have detected and removed discontinuities from data time series and estimated trends (long term signals). A frequency analysis making research of residual periodic signals and identification of the common ones to all the three space geodetic techniques has been performed. Preliminary results on co-located sites are shown