Practical evaluation of carrier sensing for a LoRa wildlife monitoring network

Morgan O'Kennedy (1) , Thomas Niesler (1) , Riaan Wolhuter (1) , Nathalie Mitton (2)

1 Department of Electrical & Electronic Engineering [Stellenbosch]
2 FUN - Self-organizing Future Ubiquitous Network

We consider the technique of carrier sensing for application in a LoRa mesh network aimed at wildlife monitoring. A key challenge in this application is to limit collisions in order to increase the channel capacity. Since CSMA is very rarely applied in LoRa-based networks, our goal is to determine its practical viability. We evaluate the LoRa Channel Activity Detection (CAD) mechanism under laboratory and field conditions. Our results show that both preamble and payload symbols are detectable even at distances exceeding 4 km. Detecting LoRa preamble symbols had a SNR advantage of between 1 and 2 dB over payload symbols. Furthermore, we find that by taking at least 8 consecutive CAD measurements, a clear channel assessment (CCA) comparable to the LoRa frame reception rate can be achieved between two nodes.

Mots clés: LoRa; CSMA; mesh network; wireless sensor networks; LPWAN

Domaines: Réseaux et télécommunications [cs.NI]

Morgan O'Kennedy, Thomas Niesler, Riaan Wolhuter, Nathalie Mitton. Practical evaluation of carrier sensing for a LoRa wildlife monitoring network. IFIP Networking, Jun 2020, Paris, France. ⟨hal-02538121⟩