An experimental combination of IGS repro3 campaign’s orbit products using a variance component estimation strategy

This is a Preprint and has not been peer reviewed. This is version 1 of this Preprint.

Downloads

Download Preprint

Authors

Pierre Sakic , Gustavo Bento Mansur , Benjamin Männel , Andreas Brack , Harald Schuh 

Abstract

Over the past years, the International GNSS Service (IGS) has put efforts into reprocessing campaigns reanalyzing the full data collected by the IGS network since 1994. The goal is to provide a consistent set of orbits, station coordinates, and earth rotation parameters using state-of-the-art models. Different from the previous campaigns - namely: repro1 and repro2 - the repro3 includes not only GPS and GLONASS but also the Galileo constellation. The main repro3 objective is the contribution to the next realization of the International Terrestrial Reference Frame (ITRF2020). To achieve this goal, several Analysis Centers (AC) submitted their specific products, which are combined to provide the final solutions for each product type. In this contribution, we focus on the combination of the orbit products.
We will present a consistent orbit solution based on a newly developed combination strategy where the weights are determined by a Least-Squares Variance Component Estimation (LSVCE). The orbits are combined in an iterative processing, first aligning all the products via a Helmert transformation, second defining which satellites will be used in the LSVCE, and finally normalizing the inverse of the variances as weights that are used to compute a weighted mean. Moreover, we will discuss the weight factors and their stability in the time evolution for each AC depending on the constellations. In addition, an external validation using a Satellite Laser Ranging (SLR) procedure will be shown for the combined solution.

DOI

https://doi.org/10.31223/X5K614

Subjects

Astrophysics and Astronomy, Earth Sciences, Navigation, Guidance, Control and Dynamics, Other Earth Sciences, Other Mathematics

Keywords

IGS, GNSS, Repro3, Variance Components Estimation, Orbit combination

Dates

Published: 2021-10-05 12:49

License

CC BY Attribution 4.0 International

Additional Metadata

Conflict of interest statement:
none

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.