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

Guido Álvarez (1) , Juan A Fraire (2) , Khaled Abdelfadeel Hassan (3) , Sandra Céspedes (4, 5) , Dirk Pesch (6)

1 CONAE - Comisión Nacional de Actividades Espaciales - Argentinian Space Agency
2 AGORA - AlGorithmes et Optimisation pour Réseaux Autonomes
3 Danalto - Danalto
4 UCHILE - Universidad de Chile = University of Chile [Santiago]
5 NIC Research Labs [Chile]
6 UCC - University College Cork

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.

Mots clés: INDEX TERMS Medium Access Control; LoRa; LR-FHSS; LoRaWAN; Direct-to-Satellite IoT

Domaines: Réseaux et télécommunications [cs.NI]

Guido Álvarez, Juan A Fraire, Khaled Abdelfadeel Hassan, Sandra Céspedes, Dirk Pesch. Uplink Transmission Policies for LoRa-Based Direct-to-Satellite IoT. IEEE Access, 2022, pp.1-1. ⟨10.1109/ACCESS.2022.3189647⟩. ⟨hal-03722756⟩