Dielectrically-Loaded Cylindrical Resonator-Based Wireless Passive High-Temperature Sensor

Abstract

The temperature sensor presented in this paper is based on a microwave dielectric resonator, which uses alumina ceramic as a substrate to survive in harsh environments. The resonant frequency of the resonator is determined by the relative permittivity of the alumina ceramic, which monotonically changes with temperature. A rectangular aperture etched on the surface of the resonator works as both an incentive and a coupling device. A broadband slot antenna fed by a coplanar waveguide is utilized as an interrogation antenna to wirelessly detect the sensor signal using a radio-frequency backscattering technique. Theoretical analysis, software simulation, and experiments verified the feasibility of this temperature-sensing system. The sensor was tested in a metal-enclosed environment, which severely interferes with the extraction of the sensor signal. Therefore, frequency-domain compensation was introduced to filter the background noise and improve the signal-to-noise ratio of the sensor signal. The extracted peak frequency was found to monotonically shift from 2.441 to 2.291 GHz when the temperature was varied from 27 to 800 °C, leading to an average absolute sensitivity of 0.19 MHz/°C.

Highly Sensitive Reentrant Cavity-Microstrip Patch Antenna Integrated Wireless Passive Pressure Sensor for High Temperature Applications

“…We can see that there is a one-to-one relationship between each temperature and the correspondent linear function which can be determined using (10) and (11). For practical application, the pressure can be obtained relying on a method called table lookup on the premise that the temperature is measured in advance via methods proposed in [3][4][5]. It can be seen from Figure 12(d) that the pressure obtained by table lookup is around the referenced pressure with a maximum error of 5.78%.…”

“…Tan et al proposed LC based sensor which can realize temperature and pressure measurement simultaneously, providing temperature compensation for pressure, making it precise for the measurement of the pressure at high temperature [3]. But the lumped circuit has low factor, causing a rapid reduction of the stored energy and a short wireless transmission distance [4,5]. For LGS (La 3 Ga 5 SiO 14 , one of piezoelectric materials) based SAW sensor, it could survive up to 1400 ∘ C, but there are several factors that limit potential use of it, including excessive conductive and viscous losses, deviations from stoichiometry, and chemical instability [6].…”

“…In addition, microwave scattering based sensor is not easy to be disturbed by ambient environment for its metal closed structure. Xiong et al proposed a resonator based wireless temperature sensor which is fabricated in alumina ceramic, realizing temperature measurement up to 800 ∘ C [4]. But due to the closed cylindrical volume of the sensor, the dimension is not small enough to make it integrated with measured object.…”

A Novel Metamaterial Inspired High-Temperature Microwave Sensor in Harsh Environments

“…In a combustion chamber, the combustion temperature directly affects the engine’s working efficiency and output power [ 3 , 4 ]. When the blade of a turbine engine runs at a high speed, an increase in the surface temperature causes the blade to deform [ 5 , 6 ]. Therefore, the applications of high-temperature sensors that are stable and function in temperatures up to 1000 °C are extensive.…”

“…This sensor can be used as temperature sensor and antenna simultaneously and its characteristic of stability at high frequencies enables its survival in harsh environments. Xiong et al [ 6 ] reported a sensor with a center frequency of 2.4 GHz which can work in temperatures from 27 to 800 °C with a sensitivity of 0.19 MHz/°C. This sensor is based on a microwave dielectric resonator and experiments have proved that it can perform effective monitoring at high temperatures.…”