Monitoring sea pollution using wireless QCM-based sensors

Nowadays, the availability of systems able to measure the pollution level in environments such as the sea and the coasts is of paramount importance in order to improve the quality of life and to prevent health issues. In this paper, a novel embedded system aimed to measure the level of pollutants in the sea water is presented. The system exploits QCM (Quartz Crystal Microbalance) in order to generate an electric signal whose frequency is a function of the concentration of the chemical agent. The frequency of the electric signal is measured using a frequency estimation algorithm that is so lightweight that it can be run even on a low-cost Internet of Things platform. Measures are sent to a remote unit using LoRaWAN, a wireless technology that supports low power wide area network communications. In this paper, a first prototype is described and preliminary experimental results are reported.