Publications Preprint · Delay-tolerant networks · 2026

Progressive Replacement Sequence Planning for Laser-Enhanced BeiDou Navigation Constellations

Huan Yan, Juan A. Fraire, Ziqi Yang, Kanglian Zhao, Wenfeng Li, Jinjun Zheng, Ziyu Wang, and Changgang Zheng

arXiv preprint, 2026

Abstract

The early satellites of the third-generation BeiDou Navigation Satellite System (BDS-3) are approaching the end of their design lifetime, making progressive constellation replacement an inevitable engineering task. Meanwhile, laser inter-satellite links (LISLs) provide high-precision time transfer, sub-millimeter-level ranging, and high-rate data forwarding capabilities, offering a promising upgrade path for future BeiDou satellites. This paper investigates the replacement-sequence planning problem for progressively replacing legacy microwave satellites with laser-enabled satellites from a networking perspective. To address this problem, three main contributions are made: (i) BeiDou progressive replacement is formulated as a network-aware launch sequence planning problem over evolving laser–microwave hybrid constellation states; (ii) an integer linear programming (ILP) model is developed to evaluate the networking gain of each candidate launch action under practical engineering constraints; and (iii) a priority-aware search heuristic is introduced to reduce the action evaluation space for efficient round-wise decision making. Simulations based on the actual BDS-3 constellation demonstrate that the proposed replacement sequence achieves a more favorable hybrid-network evolution than the historical BDS-3 launch order, including earlier formation of a ground-accessible laser-enhanced network structure, better utilization of laser-link resources, fewer residual non-anchor satellites, and lower microwave-layer waiting delay. The proposed framework can serve as a network-aware decision-support tool for future BeiDou evolution, and the resulting replacement sequence can provide direct engineering guidance for BeiDou replacement planning.

Cite

DOI 10.48550/arxiv.2607.25235

BibTeX

@article{yan2026beidou,
  author     = {Yan, Huan and Fraire, Juan A. and Yang, Ziqi and Zhao, Kanglian and Li, Wenfeng and Zheng, Jinjun and Wang, Ziyu and Zheng, Changgang},
  title      = {Progressive Replacement Sequence Planning for Laser-Enhanced {BeiDou} Navigation Constellations},
  journal    = {arXiv preprint},
  year       = {2026},
  doi        = {10.48550/arxiv.2607.25235},
  eprint     = {2607.25235},
  eprinttype = {arXiv}
}

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