Do LoRa Low-Power Wide-Area Networks Scale?

UTZ ROEDIG; MARTIN BOR; JM ALONSO; THIEMO VOIGT

Valetta

Conferencia; MSWiM 2016, the 19th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems; 2016

ACM, Association for Computing Machinery

New Internet of Things (IoT) technologies such as Long Range (LoRa) are emerging which enable power efficient wireless communication over very long distances. Devices typically communicate directly to a sink node which removes the need of constructing and maintaining a complex multi- hop network. Given the fact that a wide area is covered and that all devices communicate directly to a few sink nodes a large number of nodes have to share the commu- nication medium. LoRa provides for this reason a range of communication options (centre frequency, spreading fac- tor, bandwidth, coding rates) from which a transmitter can choose. Many combination settings are orthogonal and pro- vide simultaneous collision free communications. Neverthe- less, there is a limit regarding the number of transmitters a LoRa system can support. In this paper we investigate the capacity limits of LoRa networks. Using experiments we develop models describing LoRa communication behaviour. We use these models to parameterise a LoRa simulation to study scalability. Our experiments show that a typical smart city deployment can support 120 nodes per 3.8 ha, which is not sufficient for future IoT deployments. LoRa networks can scale quite well, however, if they use dynamic commu- nication parameter selection and/or multiple sinks.