Abstract's details

Satellite altimetry POD using GPS satellite quaternions from IGS CNES/CLS ORBEX files

Georgia Katsigianni (CLS, France)


Alexandre Couhert (CNES, France); John Moyard (CNES, France)

Event: 2022 Ocean Surface Topography Science Team Meeting

Session: Precision Orbit Determination

Presentation type: Type Oral

In the frame of improving the overall quality of satellite altimetry orbits, the contribution of high-precision GNSS measurements is essential. Nowadays, several altimeter satellites are equipped with GNSS receivers on board: Jason-3, Sentinel-3A/B, HY-2B/C/D, and Sentinel-6 Michael Freilich. Nevertheless, an accurate knowledge of the orientation of the GNSS satellites in space, especially during satellite eclipses, is a key quantity in GNSS data processing. So far, the GNSS satellite attitude is described by mathematical models (i.e. nominal yaw steering (Montenbruck et al.,2015) and auxiliary yaw steering for eclipse season (Kouba,2009) for GPS. Until recently, the International GNSS Service (IGS) proposed the publication and the exchange of GNSS satellite attitude quaternions data in ORBEX format (Loyer et al. 2019). This new information is of great importance for the calculation of carrier phase measurement time series residuals which fluctuate in the case of inaccurate attitude.

In this study we make a comparison between the two ways: a) using the existing mathematical models and b) using satellite attitude quaternions, for GNSS reference orbits. The main interest is to investigate the improvement on satellite altimetry orbits not only during the eclipse periods but also outside of these transient events. GNSS satellite products and ORBEX files are taken from the IGS CNES/CLS analysis center. The Low Earth Orbit(LEO) POD computation is performed using CNES’ ZOOM software.

Montenbruck, O., Schmid, R., Mercier F., Steigenberger P., Noll, C., Fatkulin, R., Kogure, S., Ganeshang, A.S., 2015. GNSS satellite geometry and attitude models. Adv. Space Res. 56 (6), 1015-1029. https://doi.org/10.1016/j.asr.2015.06.019

Kouba, J., 2009. A simplified yaw-attitude model for eclipsing GPS satellites. GPS Solut. 13 (1), 1-12. https://doi.org/10.1007/s10291-008-0092-1

Loyer, S., Banville, S., Geng, J., Strasser, S., 2021. Exchanging satellite attitude quaternions for improved GNSS data processing consistency. Adv. Space Res. 68 (6), 2441-2452. https://doi.org/10.1016/j.asr.2021.04.049

Oral presentation show times:

Room Start Date End Date
Sala Pasinetti Tue, Nov 01 2022,11:15 Tue, Nov 01 2022,11:30
Georgia Katsigianni