Publications Conference paper · Satellite IoT · 2026

Joint LoRa and LR-FHSS Resource Allocation Optimization in Direct-to-Satellite IoT Networks

Diego Maldonado, Megumi Kaneko, Juan A. Fraire, Alexandre Guitton, Oana Iova, and Hervé Rivano

IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM), pp. 183–192, 2026

Abstract

We investigate wireless access optimization in LoRa-based Direct-to-Satellite IoT (DtS-IoT) networks. Namely, we propose to leverage both Long Range (LoRa) and LoRa-Frequency Hopping Spread Spectrum (LR-FHSS) to support terrestrial-spatial massive IoT connectivity. To tackle this problem, we first pose LoRa uplink scheduling as a time-frequency strip packing problem, providing a 2-D integer model and a low-complexity 1-D sequential variant that serves as an upper bound on practical performance. We then design lightweight access methods that are (i) satellite-aware via per-device visibility/power/Doppler feasibility, and (ii) interference-aware via per-SF competitor counts signaled in periodic beacons. Using a Low Earth Orbit (LEO) multi-satellite scenario over continental France at 868 MHz, we show that the proposed joint LoRa+LR-FHSS strategy outperforms pure LR-FHSS once the load exceeds 20 generated packets/sec, with 10-15% higher throughput per additional LoRa channel at 50% Packet Delivery Ratio (PDR). Across a 15-minute pass, the proposed success-probabilitycontrolled access exposes the throughput-reliability trade-off and allows selecting operating points: a higher success threshold improves PDR while reducing unique receptions. Simulation results indicate that a beacon-fed plus orbit estimation policy approaches the sequential 1-D optimum, while remaining implementable on constrained devices. Also, combining LoRa and LR-FHSS improves performance in high-congestion scenarios.11This research has received support from the NII-INRIA MoU Grant funded by NII, the Grant-in-Aid for Scientific Research Kakenhi 22KK0156 from the Ministry of Education, Science, Sports, and Culture of Japan, the JST ASPIRE grant for Top Teams number JPMJAP2325, the EU's H2020 R&D program under the Marie Skłodowska-Curie grant agreement No 101008233 (MISSION project) and the French National Research Agency (ANR) projects ANR-22-CE25-0014-01 and ANR-21-CE25-0002-01.

Cite

DOI 10.1109/wowmom69805.2026.00032

BibTeX

@inproceedings{maldonado2026jointlora,
  author    = {Maldonado, Diego and Kaneko, Megumi and Fraire, Juan A. and Guitton, Alexandre and Iova, Oana and Rivano, Herv{\'e}},
  title     = {Joint {LoRa} and {LR-FHSS} Resource Allocation Optimization in Direct-to-Satellite {IoT} Networks},
  booktitle = {IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM)},
  pages     = {183--192},
  year      = {2026},
  doi       = {10.1109/wowmom69805.2026.00032}
}

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