Publications Journal article · Satellite IoT · 2022

Uplink Transmission Policies for LoRa-Based Direct-to-Satellite IoT

Guido Álvarez, Juan A. Fraire, Khaled Abdelfadeel Hassan, Sandra Céspedes, and Dirk Pesch

IEEE Access, vol. 10, pp. 72687–72701, 2022

Abstract

Direct-to-Satellite IoT (DtS-IoT) is a promising approach to deliver data transfer services to IoT devices in remote areas where deploying terrestrial infrastructure is not appealing or feasible. In this context, low-Earth orbit (LEO) satellites can serve as passing-by IoT gateways to which devices can offload buffered data to. However, transmission distances and channel dynamics, combined with highly constrained devices on the ground makes of DtS-IoT a very challenging problem. Here, we present LoRa-based approaches to realize scalable and energy-efficient DtS-IoT. Our study includes the Long Range-Frequency Hopping Spread Spectrum (LR-FHSS) physical layer, currently on the roadmap of future space IoT projects. Specifically, we propose uplink transmission policies that exploit satellite trajectory information. These schemes are framed with a theoretical Mixed Integer Linear Programming (MILP) model providing an upper bound on performance as well as inspiration for scheduled DtS-IoT solutions. Simulation results provide compelling evidence that trajectory based policies can duplicate the amount of IoT nodes, while specific variants can further boost the scalability by 30% without incurring energy penalties. We also quantify that LR-FHSS can improve the deployment scalability by a factor of 75x at the expenses of 30% higher device’s power consumption compared to the legacy LoRa modulation.

Cite

DOI 10.1109/access.2022.3189647

BibTeX

@article{DBLP:journals/access/AlvarezFHCP22,
  author  = {Guido {\'{A}}lvarez and Juan A. Fraire and Khaled Abdelfadeel Hassan and Sandra C{\'{e}}spedes and Dirk Pesch},
  title   = {Uplink Transmission Policies for LoRa-Based Direct-to-Satellite IoT},
  journal = {IEEE Access},
  volume  = {10},
  pages   = {72687--72701},
  year    = {2022},
  doi     = {10.1109/access.2022.3189647}
}

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