Publications Conference paper · Mega-constellations · 2026

Constellation Management for Inter-Satellite Link Scheduling in NB-IoT Non-Terrestrial Networks

Arnau Singla, Anna Calveras, Juan A. Fraire, and Joan A. Ruiz-de-Azua

Joint European Conference on Networks and Communications and 6G Summit (EuCNC/6G Summit), pp. 1300–1307, 2026

Abstract

Inter-Satellite Links (ISL) can improve data delivery in Low Earth Orbit (LEO) constellations by enabling relay paths when direct satellite-to-ground contacts are unavailable. However, ISL transmissions are operational tasks that consume satellite resources and affect scheduling constraints, aspects typically abstracted away in network-centric routing approaches. This paper extends our previous work, the Constellation Management System (CMS) framework, to incorporate ISL as schedulable tasks within its multi-objective optimization, jointly considering satellite operational constraints and network service metrics. We present the mathematical formulation of two ISL task types for Mobile Originated and Mobile Terminated data relay, including constraint extensions for dualsatellite memory tracking, data availability enforcement across relay chains, and end-to-end latency computation through recursive path chasing. A configurable hop limit parameter enables operators to control the trade-off between scheduling flexibility and computational complexity. Validation with a 6-satellite polar constellation demonstrates throughput improvements of up to 23% with ISL enabled, while quantifying the associated reduction in optimization speed up to 70% at two-hop configurations.

Cite

DOI 10.1109/eucnc/6gsummit68295.2026.11577303

BibTeX

@inproceedings{singla2026cmsisl,
  author    = {Singla, Arnau and Calveras, Anna and Fraire, Juan A. and Ruiz-de-Azua, Joan A.},
  title     = {Constellation Management for Inter-Satellite Link Scheduling in {NB-IoT} Non-Terrestrial Networks},
  booktitle = {Joint European Conference on Networks and Communications and 6G Summit (EuCNC/6G Summit)},
  pages     = {1300--1307},
  year      = {2026},
  doi       = {10.1109/eucnc/6gsummit68295.2026.11577303}
}

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