Evaluation of LoRa in a Real-World Smart City: Selected Insights and Findings

Abstract:
We present an evaluation of a LoRa based smart city network in Osnabrück, Germany. The main characteristic of this network is a significant gateway density in the city center. To assess the network coverage, a measurement-based study using sensors mounted on garbage trucks has been conducted. This work presents selected insights and findings emerging from the collected data. We report on inaccuracies of the RSSI reported by the deployed LoRa infrastructure which also affects various other deployments. We discuss the distribution of the SNR and the resulting Spreading Factors. In addition, we relate outdoor measurements to indoor results from different buildings and present a first idea about building attenuation. Finally, we discuss how many gateways are needed to build a LoRa based smart city network with a desired coverage for a typical city environment like Osnabrück.