Assessment of Different ITRF Realizations Using Satellite Laser Ranging

International Terrestrial Reference Frames (ITRFs) are fundamental for Earth system monitoring, satellite orbit determination, and precise positioning. They are regularly realized and provided by the three International Terrestrial Reference System (ITRS) Combination Centres (CCs) of the International Earth Rotation and Reference Systems Service (IERS): the Institut national de l’information géographique et forestière (IGN, France), the Jet Propulsion Laboratory (JPL, NASA, USA), and the Deutsches Geodätisches Forschungsinstitut at the Technical University of Munich (DGFI-TUM, Germany). Each centre applies specific combination methodologies and modeling assumptions, which can lead to subtle differences among ITRF realizations.
Within the framework of the IAG–IERS Joint Working Group 1.2.4 on the evaluation of terrestrial reference frames, this study investigates the influence of the three ITRF realizations on Satellite Laser Ranging (SLR) data analysis with a focus on the estimation of Earth Orientation Parameters (EOP).
The analysis begins by assessing the effect of the adopted ITRF realization on SLR satellite orbits and post-fit residuals, with station coordinates fixed to their a priori values. Moreover, it is examined how the selection of core SLR stations used for datum definition differs between the ITRF realizations and how these differences affect the frame’s origin, scale, and orientation. Finally, state-of-the-art SLR data processing is carried out in which orbit parameters, range biases, EOPs, and station coordinates are jointly estimated. This investigation contributes to a better understanding of the sensitivity of SLR-based products to reference frame definition and station network selection.