JTRF2020-u2022: The First Update of JTRF2020

We report on JTRF2020-u2022, the first update of JTRF2020, the most recent terrestrial reference frame (TRF) solution computed at Jet Propulsion Laboratory (JPL). Determined with SREF -a square-root information filter and Dyer-McReynolds smoother algorithm, JPL frame products lend themselves to being easily updated as long as frame inputs from the four space-geodetic technique consistent with the frame-defining data set are available. 

Adopting the conceptual framework of Bayesian update inherent to any Kalman filter formulation, SREF uploads the latest estimate of JTRF2020 state and its covariance and updates it by assimilating at daily intervals the extended frame inputs made available by IGS (IGSR3-igr3.atx), IVS (ivs2023b), ILRS (ilrsav86), and IDS (idswd23) from 2021 through the end of 2022 (DOY 330, GPS Week 2237). Afterwards, with SREF running in forecast mode, station position predictions are generated through the end of 2027 (DOY 365, GPS Week 2503).    

Discussions will focus on the peculiarities of the extended frame inputs used to compute JTRF2020-u2022 in relation to those adopted to generate JTRF2020, on the data pre-processing itself, and on the way in which the updated frame is constructed . We outline properties of  the updated TRF in terms of its frame-defining transformation parameters and present a quality assessment of  JTRF2020-u2022.