Juan A. Fraire

Researcher in Space Networking and Informatics

Inria CONICET Saarland University

Publications Conference paper · Mega-constellations · 2024

Integrating Satellite and Network Operations for NB-IoT NTN Connectivity: In-Orbit Test Design of the Constellation Management System

Arnau Singla, Anna Calveras, Francesc Betorz, Joan A. Ruiz-de-Azua, Juan A. Fraire, and Joan F. Munoz-Martin

International Astronautical Congress (IAC), Space Operations Symposium, pp. 738–749, 2024

Publisher’s version

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Abstract

With the technological advancements in software and hardware and the cost reduction of satellite launches, there has been a surge in future planned Low-Earth Orbit (LEO) constellations aimed at providing Internet of Things (IoT) services. Leveraging these constellations to extend terrestrial networks for global coverage has become a key focus, as evidenced by the standardization of Non-Terrestrial Networks (NTN) by 3GPP. However, managing operations in satellite-based NTN poses significant challenges due to the intersection of satellite operations and network management, especially in sparse constellations with intermittent connectivity. Another challenge is the need for satellite operations to adhere to standard-compliant procedures, such as those set by 3GPP standards. This ensures satellite services align with established industry practices, facilitating interoperability and compatibility with existing network infrastructures. A Constellation Management System (CMS) has been developed in response to these challenges. This system is an autonomous framework designed to seamlessly integrate satellite and network operations. The CMS integrates all the necessary agents, coordinating satellite and network operations in this heterogeneous scenario by providing business policy- and resource-aware task schedules. This facilitates the alignment of contact and task plans for satellites, ground station networks, and core networks, ultimately enabling the extension of existing terrestrial networks through satellite-based NTN. This work presents a plan to validate this novel approach through a dedicated CubeSat mission scheduled eventually for the end of 2024.

Cite

DOI 10.52202/078367-0079

BibTeX
@inproceedings{singla2024cmsiac,
  author    = {Singla, Arnau and Calveras, Anna and Betorz, Francesc and Ruiz-de-Azua, Joan A. and Fraire, Juan A. and Munoz-Martin, Joan F.},
  title     = {Integrating Satellite and Network Operations for {NB-IoT} {NTN} Connectivity: In-Orbit Test Design of the Constellation Management System},
  booktitle = {International Astronautical Congress (IAC), Space Operations Symposium},
  pages     = {738--749},
  publisher = {IAF},
  year      = {2024},
  doi       = {10.52202/078367-0079}
}

More on mega-constellations

  1. On the Use of Mega Constellation Services in Space: Integrating LEO Platforms Into 6G Non-Terrestrial Networks Gabriel Maiolini Capez, Mauricio A. Cáceres, Roberto Armellin, Christopher P. Bridges, Juan A. Fraire, Stefan Frey, and Roberto Garello IEEE Journal on Selected Areas in Communications, 2024
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    This paper presents a framework for integrating Low-Earth Orbit (LEO) platforms with Non-Terrestrial Networks (NTNs) in the emerging 6G communication landscape. Our work applies the Mega-Constellation Services in Space (MCSS) paradigm, leveraging LEO mega-constellations’ expansive coverage and capacity, designed initially for terrestrial devices, to serve platforms in lower LEO orbits. Results show that this approach overcomes the limitation of sporadic and time-bound satellite communication links, a challenge not fully resolved by available Ground Station Networks and Data Relay Systems. We contribute three key elements: (i) a detailed MCSS evaluation framework employing Monte Carlo simulations to assess space user links and distributions; (ii) a novel Space User Terminal (SUT) design optimized for MCSS, using different configurations and 5G New Radio Adaptive Coding and Modulation; (iii) extensive results demonstrating MCSS’s substantial improvement over existing Ground Station Networks and Data Relay Systems, motivating its role in the upcoming 6G NTNs. The space terminal, incorporating a multi-system, multi-orbit, and software-defined architecture, can handle Terabit-scale daily data volumes and minute-scale latencies. It offers a compact, power-efficient solution for properly integrating LEO platforms as space internet nodes.

  2. RF-Assisted Uncertainty Cone Reduction in Free-Space Optical Inter-Satellite Links Elena Fernández-Niño, Juan A. Fraire, Adriano Camps, and Joan Adrià Ruiz-de-Azua IEEE Open Journal of the Communications Society, 2024
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  3. Anyone, Anywhere, not Everyone, Everywhere: Starlink Doesn't End the Digital Divide Wesley Woo, Juan A. Fraire, Sylvia Ratnasamy, Scott Shenker, and Shaddi Hasan ACM Workshop on Hot Topics in Networks (HotNets), 2025
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