caa a22 4500 606245200 CHVBK 20210128101334.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s12567-014-0069-6 doi (NATIONALLICENCE)springer-10.1007/s12567-014-0069-6 Preparing an autonomous, low-cost GNSS positioning and timing function on board a GEO telecom mission: a study case [Elektronische Daten] [A. Zin, M. Scotti, E. Mangolini, I. Cappelluti, R. Fiordiponti, J. Amalric, P. Flament, E. Brouillard, S. Kowaltschek] The purpose of this paper is to present a viable solution for a low-cost, autonomous GNSS positioning and timing function integrated in the avionics of a GEO telecomm satellite. This paper is based on a study currently carried out by Thales Alenia Space under an ARTES contract with ESA, funded by the Italian Space Agency. The availability of an autonomous means of positioning in GEO platform is essential in reducing the constraints on the ground control. This is even more true in the case of the transfer to the GEO orbit, where the current trend is to implement the low-thrust electrical propulsion and this phase could have a duration of months: the GNSS function can autonomously feed the on-board trajectory propagator with the spacecraft position fixes, in order to constrain the state estimate of the on-board filter. In order to achieve large availability of position and timing of the hosting platform, the tracking of the GNSS antenna side lobes is a critical feature. Based on the recent experiences of SGR GEO, additional insights on the side-lobe levels were made available to the GNSS community and this allows to better target a receiver architecture whose performance can be more precisely determined for the study case. This paper will show the findings in terms of GNSS function architecture for the GEO application, as well as the integration of this function inside the avionic computer. The focus is on a single frequency receiver, targeting at least GPS L1 and Galileo E1 signals. Optimizations in terms of sharing of HW resources with the on-board computer (oscillator, DC/DC converter) and the overall redundancy strategy are presented. Extension and implications for covering to the GTO case is presented as well. The expected receiver performances (position and timing accuracy, autonomy) are provided through in-orbit simulations, including a realistic receiver model. CEAS, 2015 GNSS nationallicence Space receiver nationallicence AGGA-4 nationallicence GTO nationallicence Navigation nationallicence Electrical propulsion nationallicence Zin A. Thales Alenia Space, Milan, Italy aut Scotti M. Thales Alenia Space, Milan, Italy aut Mangolini E. Thales Alenia Space, Milan, Italy aut Cappelluti I. Thales Alenia Space, Milan, Italy aut Fiordiponti R. Thales Alenia Space, Milan, Italy aut Amalric J. Thales Alenia Space, Cannes, France aut Flament P. Thales Alenia Space, Cannes, France aut Brouillard E. Thales Alenia Space, Cannes, France aut Kowaltschek S. European Space Agency (ESA), Noordwijk, The Netherlands aut CEAS Space Journal Springer Vienna 7/2(2015-06-01), 247-262 1868-2502 7:2<247 2015 7 12567 https://doi.org/10.1007/s12567-014-0069-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s12567-014-0069-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zin A. Thales Alenia Space, Milan, Italy aut NATIONALLICENCE 700 1- Scotti M. Thales Alenia Space, Milan, Italy aut NATIONALLICENCE 700 1- Mangolini E. Thales Alenia Space, Milan, Italy aut NATIONALLICENCE 700 1- Cappelluti I. Thales Alenia Space, Milan, Italy aut NATIONALLICENCE 700 1- Fiordiponti R. Thales Alenia Space, Milan, Italy aut NATIONALLICENCE 700 1- Amalric J. Thales Alenia Space, Cannes, France aut NATIONALLICENCE 700 1- Flament P. Thales Alenia Space, Cannes, France aut NATIONALLICENCE 700 1- Brouillard E. Thales Alenia Space, Cannes, France aut NATIONALLICENCE 700 1- Kowaltschek S. European Space Agency (ESA), Noordwijk, The Netherlands aut NATIONALLICENCE 773 0- CEAS Space Journal Springer Vienna 7/2(2015-06-01), 247-262 1868-2502 7:2<247 2015 7 12567