Environmental Monitoring Using Low-Cost Hardware and Infrastructureless Wireless Communication

Infrastructureless wireless sensing is beneficial for environmental monitoring in various application scenarios, such as in a disaster where it is vital for the operational planning of professional responders, or in documenting long-term changes in climate and biodiversity in natural heritage sites. In this paper, we present a low-cost yet flexible and powerful hardware/ software platform for sensing, computation, and infrastructureless wireless communication. Since energy usage is a key issue for autonomous operation, we investigate the power requirements of various computing platforms, sensors and radio link technologies. Furthermore, we experimentally evaluate several license-free radios (WiFi, Bluetooth, LoRa 433 MHz and 868 Mhz) in terms of their real-world communication ranges. To avoid wasting precious communication resources, we apply machine learning and imagebased concept detection on-device to remove irrelevant data before sending it. We also evaluate neural compute sticks to improve performance and optimize their power consumption in our scenario. The proposed hardware/ software platform consists of small, low-power sensor nodes based on microcontrollers, larger single board computer relay nodes that can also preprocess data, and Bluetooth Low Energy enabled smartphone add-ons to give mobile devices access to long range communication technology. Finally, a Linux distribution tailored to the specific needs in this application area is presented that makes deploying new relay nodes easy even for non-specialists.