TDD LoRa and Delta Encoding in Low-Power Networks of Environmental Sensor Arrays for Temperature and Deformation Monitoring

Abstract

Densely distributed sensor networks can revolutionize environmental observations by providing real-time data with an unprecedented spatiotemporal resolution. However, field deployments often pose unique challenges in terms of power provisions and wireless connectivity. We present a framework for wirelessly connected distributed sensor arrays for near-surface temperature and/or deformation monitoring. Our research focuses on a novel time division duplex implementation of the LoRa protocol, enabling battery powered base stations and avoiding collisions within the network. In order to minimize transmissions and improve battery life throughout the network, we propose a dedicated delta encoding algorithm that utilizes the spatial and temporal similarity in the acquired data sets. We implemented the developed technologies in a AA battery powered hardware platform that can be used as a wireless data logger or base station, and we conducted an assessment of the power consumption. Without data compression, the projected battery life for a data logger is 4.74 years, and a wireless base stations can last several weeks or months depending on the amount of network traffic. The delta encoding algorithm can further improve this battery life with a factor of up to 3.50. Our results demonstrate the viability of the proposed methods for low-power environmental wireless sensor networks.

Model and remote-sensing-guided experimental design and hypothesis generation for monitoring snow-soil–plant interactions

“…In addition, sporadic ground-based surveys such as snow course measurements are still important to cover a larger space between fixed sensors and to create site-specific relationships with remote sensing data (Dressler et al, 2006). In particular, our approach is promising to guide the optimal deployment of wireless sensor networks (e.g., Oroza et al, 2016;Wielandt et al, 2023), in which the value of sensing various properties of interest might need to be balanced by the site accessibility, sensor resolution and accuracy, power requirement, wireless connectivity, total data cost, and complementarity to remote sensing products and other datasets.…”