Publications Journal article · Satellite IoT · 2025

FLoRaSat 2: Simulating Cross-Linked Direct-to-Satellite IoT LEO Constellations with Joint Access and Routing Evaluation

Alexander Y. Choquenaira-Florez, Benoit Coeugnet, Robin Ohs, Juan A. Fraire, and Hervé Rivano

Wiley International Journal of Satellite Communications and Networking, 2025

Abstract

Direct-to-Satellite IoT (DtS-IoT) has emerged as a promising solution for extending IoT connectivity to remote regions where terrestrial infrastructure is impractical or economically unfeasible. In such scenarios, Low-Earth Orbit (LEO) satellites act as mobile in-orbit gateways, but their dynamic nature and reliance on constrained Inter-Satellite Links (ISLs) introduce significant challenges for medium access, routing, and end-to-end performance evaluation. To address these issues, we present FLORASAT 2, an open-source, event-driven simulator based on OMNET++. The first version of FLORASAT focused on device-to-satellite communication, providing a unique tool to study LoRa/LoRaWAN-based DtS-IoT systems. The present work advances FLORASAT 2 into a full end-to-end simulation framework by integrating Medium Access Control (MAC) protocols with constellation-grade routing models, including constellation creation, dynamic ISL topology control, and a sandbox for benchmarking routing algorithms such as Directed, DDRA, and DiscoRoute. Notably, it introduces K-MAC, a repetition-based MAC scheme designed to improve resilience under Doppler effects, congestion, and intermittent visibility, while expanding the satellite and device modules to support multiple MAC protocols beyond LoRaWAN. To the best of our knowledge, FLORASAT 2 is the only open-source simulator capable of jointly evaluating access and routing layers for constellation-grade DtS-IoT networks. Through extended benchmark scenarios on Starlink-and Iridiumlike constellations, we demonstrate how the integration of MAC and routing enables a more realistic and holistic assessment of network performance, positioning FLORASAT 2 as a versatile platform for the design and optimization of next-generation satellite IoT systems.

Cite

BibTeX

@article{choquenaira2025florasat2,
  author  = {Choquenaira-Florez, Alexander Y. and Coeugnet, Benoit and Ohs, Robin and Fraire, Juan A. and Rivano, Herv{\'e}},
  title   = {{FLoRaSat} 2: Simulating Cross-Linked Direct-to-Satellite {IoT} {LEO} Constellations with Joint Access and Routing Evaluation},
  journal = {Wiley International Journal of Satellite Communications and Networking},
  year    = {2025},
  url     = {https://hal.science/hal-05424077}
}

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