Characterization of LoRa Point-to-Point Path Loss: Measurement Campaigns and Modeling Considering Censored Data

Low-power wide-area technologies have demonstrated their usefulness in a wide variety of Internet of Things applications. New applications are emerging, requiring a mesh or point-to-point (P2P) topology, in contrast to the conventional star-of-stars topology. In this article, we evaluate the coverage and model the path loss (PL) of these links, based on experimental campaigns in three environments: 1) urban; 2) forest; and 3) coastal. More obstructions, scattering, and diffraction are encountered because the terminals are typically at a low height. This results in a higher PL compared to the star-of-stars topology. Consequently, more packets drop below the receiver sensitivity. Realistic PL parameters are estimated by also taking the censored data into account. The packet error ratio is determined based on the estimated PL parameters to evaluate the performance of P2P links. Even in these adverse environments, 80% of the transmitted packets are successfully received at a distance of approximately 200 m. Moreover, a range of over 4 km is observed in the line-of-sight scenario. Despite the unfavorable radio propagation in the urban scenario and the densely forested terrain, a maximum range of 1 km is achieved.