Wireless Temperature Measurements above 500°C using Surface Acoustic Wave Sensors

摘要

Surface acoustic wave (SAW) devices can operate without on-board power supply using a dedicated interrogation unit. Using appropriate design considerations, these devices are sensitive to parametric perturbations including temperature, pressure, strain, etc. The work reported in this paper has been developed in the SAWHOT (NMP Europa/Russia) project frame, consisting in measuring temperature in harsh environments like high temperature furnace, airplane engines or chemical reactors. Temperature sensors operating from room temperature up to 700°C are particularly focused here. Below 500°C, the use of a Quartz-based differential SAW sensor is demonstrated, allowing for accurate measurements with an effective robustness to environmental conditions. Above 500°C, Langasite (LGS)-based SAW resonators are used, allowing for temperature measurements up to 700°C during several tens of hours.