An Embedded Passive Resonant Sensor Using Frequency Diversity Technology for High-Temperature Wireless Measurement

This paper presents an embedded wireless passive temperature sensor for measurements in high-temperature applications, such as compressors and turbine engines. The performance of the sensor was improved by optimizing its performance parameters. A high-temperature-resistant material was used, and an embedded structure design was introduced to enable the sensor to operate in high-temperature environments. A series LC resonant circuit containing a fixed inductance coil and variable capacitance that varies with temperature was embedded in an alumina ceramic substrate using high-temperature cofired ceramic technology. The temperature in the high-temperature environment was detected wirelessly via the frequency diversity of the sensor. Furthermore, the experimental results showed that the sensor can measure temperatures ranging from room temperature to 1000 °C, and the average sensitivity of the sensor is ~2 KHz/°C.