Spatial issues in modeling Lorawan capacity

Abstract

All existing models for analyzing the performance of LoRaWAN assume a constant density of nodes within the gateway range. We claim that such a situation is highly unlikely for LoRaWAN cells whose range can attain several kilometers in real-world deployments. We thus propose to analyze the LoRa performance under a more realistic assumption: the density of nodes decreases with the inverse square of the distance to the gateway. We use the LoRaWAN capacity model by Georgiou and Raza to find the Packet Delivery Ratio (PDR) for an inhomogeneous spatial distribution of devices around a gateway and obtain the number of devices that benefit from a given level of PDR. We analyze the LoRaWAN capacity in terms of PDR for various spatial configurations and Spreading Factor allocations.