A Propagation Study of LoRa P2P Links for IoT Applications: The Case of Near-Surface Measurements over Semitropical Rivers

Abstract

Internet of Things (IoT) radio networks are becoming popular in several scenarios for short-range applications (e.g., wearables and home security) and medium-range applications (e.g., shipping container tracking and autonomous farming). They have also been proposed for water monitoring in flood warning systems. IoT communications may use long range (LoRa) radios working in the 915 MHz industrial, scientific and medical (ISM) band. In this research, we study the propagation characteristics of LoRa chirp radio signals close to and over water in a tropical meadow region. We use as a case study the Colima River in Mexico. We develop a novel point-to-point IoT measurement sounding system that does not require decoding of LoRa propriety bursts and provides accurate power versus distance profiles along the riparian zone of a steeply dropping mountain river. We used this system to obtain the measurements reported in this work, which are also analyzed and modeled. The results show that the LoRa signal propagation over water exhibits a log-normal distribution. As a result of the chirp signal processing, two new experimental path loss models are presented. The path loss results show a considerable degradation of the received signal power over water within vegetation and less signal degradation at antenna heights closer to the water surface.

Modeling LoRa Communications in Estuaries for IoT Environmental Monitoring Systems

“…This is in contrast with the current trend in IoT-driven application scenarios (e.g., water-quality monitoring, flooding prevention, etc. ), which often require (shorter) links at near-shore with antennas relatively close to the surface [29], [30]. These different implementation settings imply tides can induce changes on the water level that are in the order of magnitude of the antenna height, possibly intensifying tidal fading and other propagation effects.…”

LoRa Technology Propagation Models for IoT Network Planning in the Amazon Regions

“…Monitoring, tracking, and locating objects are applications of LoRaWAN technology in maritime environments. Whether monitoring natural disasters, water quality, or vessels, the technology delivers significant results in cost-effectiveness and real-time collection [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ].…”

“…Regarding water environments, measurements and channel modeling through LoRa technology are most commonly performed in maritime environments [ 9 , 22 ]. Few studies present channel modeling, coverage, or packet reception efficiency results in riverine environments [ 23 , 24 ]. However, the rivers in those studies have different characteristics from Amazonian rivers, which do not feature dense vegetation on their banks.…”

Evaluation of Radio Communication Links of 4G Systems

“…It is a Bayesian particle filter used for overcomes the noise caused by obstacles and sudden signal fading. The power of pure chirp signals from a long-range end-devices radio is applied in [ 13 ] to avoid missing information and inaccurate path loss exponent values. It is a case study of point-to-point Internet of Things radio networks measurement.…”