Publications Journal article · Mega-constellations · 2024

Toward Optimal Placement of Free-Space Optical Terminal on the Spacecraft Body

Juan A. Fraire, Joan Adrià Ruiz-de-Azua, and Elena Fernández-Niño

IEEE Transactions on Aerospace and Electronic Systems, vol. 60, no. 6, pp. 8914–8928, 2024

Abstract

Free-space optical (FSO) links have emerged as a promising solution for enabling high-speed data transfer in networked space systems. These links leverage highly directed optical beams amplified by telescopes that can be oriented using gimbal engines. However, the gimbal's limited swipe range poses a challenge in optimizing the placement of the FSO terminal on the satellite body. This placement directly impacts the feasible contact time, which is constrained by the gimbal motors' degree of freedom and speed as the satellites follow their orbital trajectories. In this article, we address the problem of optimizing the FSO terminal placement to maximize the aggregate effective contact time with the target. First, we formally describe the problem assumptions and perform baseline case studies to gain valuable insights. Next, we define appropriate metrics that capture the contact time performance to evaluate different placement strategies. Our core contributions are two heuristics, simulated annealing, and an evolutionary genetic algorithm to optimize the FSO terminal placement. We finally demonstrate through extensive simulation and analysis that our proposed optimization approaches can significantly improve the baseline contact time by up to 27.7%. These findings highlight the potential of employing sophisticated optimization techniques to enhance the performance of FSO links.

Cite

DOI 10.1109/taes.2024.3435176

BibTeX

@article{DBLP:journals/taes/FraireAF24,
  author  = {Juan A. Fraire and Joan Adri{\`{a}} Ruiz{-}de{-}Azua and Elena Fern{\'{a}}ndez{-}Ni{\~{n}}o},
  title   = {Toward Optimal Placement of Free-Space Optical Terminal on the Spacecraft Body},
  journal = {IEEE Transactions on Aerospace and Electronic Systems},
  volume  = {60},
  number  = {6},
  pages   = {8914--8928},
  year    = {2024},
  doi     = {10.1109/taes.2024.3435176}
}

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