Publications Journal article · Delay-tolerant networks · 2022

Contact Plan Design for GNSS Constellations: A Case Study With Optical Intersatellite Links

Andrea Nardin, Juan A. Fraire, and Fabio Dovis

IEEE Transactions on Aerospace and Electronic Systems, vol. 58, no. 3, pp. 1981–1995, 2022

Abstract

Optical Intersatellite Links (OISLs) are being considered for future Global Navigation Satellite System (GNSS) constellations. Thanks to OISLs, the constellation incorporates improved clock synchronization and precise ranging among the satellites, which are essential features to achieve accurate time and orbit determination. High data rate communications within the space segment also reduce ground segment dependency, by means of decentralized access to information. However, the dual optimization of data and navigation performance metrics requires a careful assignment of OISLs to the available laser communication terminals on-board. To this end, we present a contact plan design scheme based on a degree constrained minimum spanning tree heuristic applied to such OISL-enabled GNSS (O-GNSS) constellations. Results on the Kepler system, a novel GNSS proposal, show that a fair distribution of connectivity among the constellation can be ensured while optimizing its range-based position estimation capabilities (PDOP). A PDOP improvement of 85 % is reached on average by the optimized contact plan with respect to a generic scheduler that disregards the geometrical distribution of the chosen links.

Cite

DOI 10.1109/taes.2021.3135025

BibTeX

@article{DBLP:journals/taes/NardinFD22,
  author  = {Andrea Nardin and Juan A. Fraire and Fabio Dovis},
  title   = {Contact Plan Design for {GNSS} Constellations: {A} Case Study With Optical Intersatellite Links},
  journal = {IEEE Transactions on Aerospace and Electronic Systems},
  volume  = {58},
  number  = {3},
  pages   = {1981--1995},
  year    = {2022},
  doi     = {10.1109/taes.2021.3135025}
}

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