VLBI and GPS inter- and intra-technique combinations on the observation level for evaluation of TRF and EOP

Abstract We study the effects of combination on observation level (COL) different space-geodetic techniques and networks same technique present corresponding improvement for determination station positions earth orientation parameters. Data from continuous geodetic very long baseline interferometry (VLBI) campaign CONT17 are used in a batch least-squares (LSQ) estimator. This includes 15 days observations with two legacy S/X networks, namely Legacy-1 (L1) Legacy-2 (L2). For this VLBI L1 network is as base reference solution. combined first data co-located Global Positioning System (GPS) stations by estimating common tropospheric The derived repeatabilities GPS evaluated respect to single-technique solutions. In terms precision, we find 25% vertical repeatability network, 10% horizontal one. also benefits 20% components, respectively. Furthermore, solution using L2 performed L1&GPS L1&L2 solutions compared investigating UT1 polar motion estimates. mean bias formal errors International Earth Rotation Service (IERS) C04 products which were priori values. has lowest error 30% improvement. weighted root square (WRMS) offset (WMO) differences between obtained estimates ones GNSS (IGS) compared. that gives WRMS WMO, exhibiting an average 40% presented results highlight potential COL ongoing transition multi-space analysis, e.g., Navigation Satellite Systems (GNSS) next-generation system. Graphic