Method of Assigning Spreading Factor to Improve the Scalability of the LoRaWan Wide Area Network

In modern world Low Power Wide Area Network (LPWAN) technologies have become the key enabler for a sheer diversity of the Internet of Things (IoT) applications involving massive deployment of resource-limited devices. In this paper we address the problem of improving the network scalability for one of the most widely used today licensee-free-band LPWAN technologies, named LoRaWAN. We show that the conventional method for assigning the spreading factor (SF) parameter to the devices in a LoRaWAN network, which effectively minimizes the consumption of individual devices, has some drawbacks when this comes to the scalability of the network as whole. Therefore, in this paper we propose another method of assigning the SFs to the nodes, which improves the probability of data delivery in an LPWAN at a cost of minor increase of the devices' consumption. The results of the conducted simulations confirm and characterize the utility of the proposed method.