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Technical Paper
J. Astron. Space Sci. 38(1), 65-82 (2021)
https://doi.org/10.5140/JASS.2021.38.1.65
Copyright © The Korean Space Science Society
Geostationary Satellite Station Keeping Robustness to Loss of Ground
Control
Hyung Je Woo
1†
, Bjorn Buckwalter
2
1
Agency for Defense Development, Daejeon 34060, Korea
2
Satconsult, Toulouse 31000, France
For the vast majority of geostationary satellites currently in orbit, station keeping activities including orbit determination and
maneuver planning and execution are ground-directed and dependent on the availability of ground-based satellite control
personnel and facilities. However, a requirement linked to satellite autonomy and survivability in cases of interrupted ground
support is often one of the stipulated provisions on the satellite platform design. It is especially important for a geostationary
military-purposed satellite to remain within its designated orbital window, in order to provide reliable uninterrupted
telecommunications services, in the absence of ground-based resources due to warfare or other disasters. In this paper we
investigate factors aecting the robustness of a geostationary satellite’s orbit in terms of the maximum duration the satellite’s
station keeping window can be maintained without ground intervention. By comparing simulations of orbit evolution,
given dierent initial conditions and operations strategies, a variation of parameters study has been performed and we have
analyzed which factors the duration is most sensitive to. is also provides valuable insights into which factors may be worth
controlling by a military or civilian geostationary satellite operator. Our simulations show that the most benecial factor for
maximizing the time a satellite will remain in the station keeping window is the operational practice of pre-emptively loading
East-West station keeping maneuvers for automatic execution on board the satellite should ground control capability be lost.
e second most benecial factor is using short station keeping maneuver cycle durations.
Keywords:
GEO satellite, station keeping window, station keeping maneuver, orbit evolution, autonomy, loss of ground control
1. INTRODUCTION
The Republic of Korea Government (ROK-G) relies on
in-orbit resources to meet military telecommunications
needs. These in-orbit resources include geostationary
telecommunications satellites which, in order to provide
eective and interference-free telecommunications services,
have stringent requirements on their orbit geometry.
These requirements in turn impose operational activities,
collectively referred to as station keeping, in order to maintain
an appropriate orbit geometry:
1. Measuring the orbit (orbit determination).
2. Planning and execution of station keeping maneuvers
using on-board propulsion systems in order to counter
the deterioration of the orbit due to perturbing forces.
These activities are typically orchestrated on a regular
schedule, known as a station keeping cycle, by staff in the
satellite operator’s satellite control center. A typical station
keeping cycle duration is one or two weeks. Dedicated
telemetry, tracking and control (TTC) Earth station antennas
are used for orbit determination and satellite commanding.
e availability and quality of telecommunication services
utilizing geostationary satellites are clearly dependent
on the availability of the satellite control center and TTC
antennas. Recognizing that the availability of such ground-
based resources can be compromised by natural disaster or
This is an Open Access article distributed under the terms of the
Creative Commons Attribution Non-Commercial License (https://
creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted
non-commercial use, distribution, and reproduction in any medium,
provided the original work is properly cited.
Received 12 NOV 2020 Revised 05 FEB 2021 Accepted 16 FEB 2021
†
Corresponding Author
Tel: +82-42-821-4187, E-mail: hyungje_woo@add.re.kr
ORCID: https://orcid.org/0000-0003-0601-5687
