Sentinel-6 orbit determination at the Copernicus POD Service

Autor: Peter, Heike, Fernández, Jaime, Fernández, Marc, Féménias, Pierre, Andres, Yago, Nogueira Loddo, Carolina
Rok vydání: 2022
DOI: 10.24400/527896/a03-2022.3271
Popis: Sentinel-6 Michael Freilich satellite launched in November 2020 is the first satellite carrying a combined GPS and Galileo receiver for precise orbit determination (POD). In addition, it is equipped with a DORIS receiver and a Laser Retro Reflector for Satellite Laser Ranging (SLR). The GNSS-RO (radio occultation) instrument also has a POD antenna. This allows for various cross-comparisons between orbits from the different observation techniques and instruments. The Copernicus POD Service is a consortium responsible for providing orbit products and auxiliary data files from the Copernicus Sentinel-1, -2, -3, and -6 missions to the corresponding ground segment processing chains at ESA and EUMETSAT. Products and data are also made available to external users through the ESA Copernicus Open Access Hub. For Sentinel-6A, a near real-time orbit product computed based on GNSS data, is delivered to EUMETSAT, the DORIS DIODE aboard acting as backup. The Regular Service Reviews (quarterly and one yearly) also include validation of post-processed Sentinel-6 orbit solutions from various members of the Copernicus POD Quality Working Group (QWG). Focus of this contribution is on post-processed POD based on the combined GPS/Galileo receiver and validation with SLR done at the Copernicus POD Service. Precise orbits may be derived as single-system or combined solutions. Integer ambiguity resolution is a key technique to obtain highest accuracy orbits. The dynamic modelling of the satellite orbit also benefits from updates and improvements of the satellite macro model. We present orbit determination results from GPS-only, Galileo-only and combined GPS & Galileo observations with resolved integer ambiguities and using different satellite macro models. Cross-comparison between the different solutions, SLR validation, and comparison to other orbit solutions provided by members of the Copernicus POD QWG are shown and analysed.
Databáze: OpenAIRE