High availability wireless temperature sensors for harsh environments

The recent improvements in RF devices transformed wireless sensor networking into a reality. Advantages deriving from the cable removal are well known, especially in industrial applications where large part of the cost is due to wire routing and related maintenance. A lot of studies have been proposed in the past to analyze and anticipate obtainable performance in harsh environments, but only few reports real world experiments. In this work, a wireless system for temperature measurement is proposed. Specifically, a distributed coordinator approach allows implementing a redundant star network topology ensuring high availability and reliability also in harsh environments. The realized system is designed to operate into a vessel subject to very extreme conditions, including an extended temperature and pressure range (from -5 to +140 °C and up to 5 bar) with the presence of humidity (RH 100% condensing). In particular, the RF signal quality has been experimentally verified also in such a critical environment.