Research of SAW Temperature and Pressure Dual Parameter Measuring Sensor Based on Delay Line Type

Surface acoustic wave (SAW) temperature and pressure sensors have been rapidly developed. A surface acoustic wave sensor with a dual-port delay line structure was designed and optimized by COMSOL software. The temperature and pressure measurement accuracy of the sensor is studied. In the signal measurement system, the signal is processed by the mixing detection method and the phase detection method. The perturbation quantity of pressure and temperature can be obtained by analyzing the perturbation relation between frequency and pressure, phase, and temperature. The results show that the sensitivity of the sensor is 339.175 kHz/Nin the micro-pressure measurement of 0-0.2 N. The frequency error after optimization is between -3.3 and 4 kHz, and the error rate is 2.95%. In the case of 25-95 degrees C, the sensitivity of the sensor is 0.045861 rad/degrees C. It lays a foundation for the research of the SAW multi-parameter measuring sensor.