Abstract
This work investigates challenges and solutions related to the coexistence of LoRaWAN networks operating within the EU868 spectrum. After describing the possible channel options in this spectrum, graph theory is employed to model the degree of interference between overlapping networks, focusing on the identification of shared channels to minimize interference. Channel group arrangement schemes and a graph coloring solution aimed at improving network performance and enhancing overall communication efficiency are proposed. The effectiveness of the solution is assessed through a real-world deployment involving over 10,000 end-devices, 28 gateways, and 7 network servers for an equal number of subnetworks. The results show that the proposed approach improves the packet reception ratio (PRR) by 7 percentage points compared to the case where only one channel group is assigned across the entire network. The overall uplink fairness is also improved.