LoRa in a haystack: a study of the LoRa signal behavior

International audienceOver the years, LoRa has been raising a lot of interest, both from the academia and the industry. LoRa is indeed a promising technology that enables long range and low power communications to connect IoT devices to the Internet. LoRa is often envisioned for several applications such as regular reporting but it is also aimed to be exploited for other applications, such as geolocation for instance. However, current implementations of LoRa geolocation system or other alternative applications suffer from severe inaccuracy. The purpose of this paper is to investigate where the inaccuracy comes from but also to determine LoRa technology based geolocation best uses-cases. The paper characterizes the LoRa radio signal properties, through a real validation campaign, over different contexts and different LoRa physical layer settings. Our results show that the signal properties, such as RSSI or SNR, are more stable in a peri-urban area than in a high density urban area. In the latter scenario, we also observe an asymmetric reception