LoRaWAN Transmissions in Salt Water for Superficial Marine Sensor Networking: Laboratory and Field Tests

Abstract

In this paper, the authors present the results of a set of measurements carried out to analyze the transmission capabilities of the LoRaWAN technology for underwater to above water transmission in saline water. A theoretical analysis was used to model the link budget of the radio channel in the considered operative conditions and to estimate the electrical permittivity of salt water. Preliminary measurements were performed in the laboratory at different salinity levels to confirm the application boundaries of the technology, then field tests were conducted in the Venice lagoon. While these test are not focused on demonstrating the usability of LoRaWAN to collect data underwater, the achieved results demonstrate that LoRaWAN transmitters can be used in all those conditions when they are expected to be partially or totally submerged below a thin layer of marine water, in accordance with the prediction of the proposed theoretical model. This achievement paves the way for the deployment of superficial marine sensor networks in the Internet of Underwater Things (IoUT) context, as for the monitoring of bridges, harbor structures, water parameters and water sport athletes and for the realization of high-water or fill-level alarm systems.

Doppler Shift and SFO Robust Synchronization for LoRa-Like Acoustic Underwater Communication

“…Commercial available RF transceivers can be used for transmission ranges over a few meters in the water. The authors in [56] used LoRaWAN with a slightly submerged sensor node and a gateway outside of the water. The communication link was stable, when the node was a few centimeter below the water surface.…”

A Salinity-Impact Analysis of Polarization Division Multiplexing-Based Underwater Optical Wireless Communication System with High-Speed Data Transmission

“…The effects of saline water not only restrict the deployment of underwater devices but also impose stringent limitations on the positioning of data transmission tools in areas with high water salinity [2,3]. This scenario is particularly relevant for floating structures where successful transmissions necessitate antennas to be elevated at specific heights above saline water to overcome its attenuating effects and ensure reliable communication [4]. However, the challenges become even more pronounced when data transmission needs to occur underwater in environments with high salinity.…”