Related Experiment Video
Updated: Oct 15, 2025

A Low-Cost Method of Measuring the In Situ Primary Productivity of Periphyton Communities of Lentic Waters
Published on: December 16, 2022
A Propagation Study of LoRa P2P Links for IoT Applications: The Case of Near-Surface Measurements over Semitropical
Amado Gutiérrez-Gómez1, Víctor Rangel1, Robert M Edwards2
1School of Engineering, National Autonomous University of Mexico (UNAM), Building Q-Valdes Vallejo, Ciudad Universitaria, Delegación de Coyoacán, CDMX, Mexico City 04510, Mexico.
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.
Related Concept Videos
Propagation of Waves
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
Propagation Speed of Electromagnetic Waves
Short-distance Transport of Resources
Propagation of Action Potentials
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
Energy Considerations in Open Channel Flow
Xylem and Transpiration-driven Transport of Resources

