A Tree-Structured LoRa Network for Energy Efficiency

The LoRa technology is considered as one of the most potential solutions for Internet of Things (IoT) in the near future. The existing LoRa networks are based on the star topology. In this article, a tree network adopted for the LoRa technology and a communication protocol are proposed to mitigate the energy consumption constraints. In the proposed network, the nodes are self-configured based on the LoRa physical link behavior and can act as relays to propagate data from other nodes. The analysis, design, and evaluation of the proposed architecture for large scale LoRa networks are presented in detail. With analytical studies, the energy consumption of the star and tree LoRa networks are compared. The presented analytical results can provide developers with effective guidelines for scalable design and optimization of LoRa networks. Further, the results are verified using simulation and experimental tests. Both simulation and experimental results confirm that the presented method improves the energy consumption of the entire IoT network significantly. As a result, the presented tree network can be deployed in various applications.