一种可同时测量温度和压力的新型SAW传感器

针对汽车轮胎压力监测系统（TPMS）的典型应用,提出了一种基于声表面波（SAW）的新型传感器.这用SAW延迟线理论,温度和压力对于传感器的影响能够通过射频回波信号的变化反映出来.通过在数据处理中引入权重因子,实现对于温度和压力的准确测量.在一定压力（0-200 kPa）和温度（20-100℃）范围内的测试结果表明,该传感器能够同时准确测量温度和压力.SAW传感器对温度的测量精度可以达到0.05℃,对压力的测量精度可以达到7.2 kPa.在对于可靠性和耐久性具有特殊要求的汽车轮胎压力监测等领域,该传感器简单的结构和无线无源的测量方式,进一步提高了其实用性和推广价值.

A Novel SAW Sensor for Temperature and Pressure Measurement

For the typical applications of automotive tire pressure monitoring system (TPMS), a novel sensor based on surface acoustic wave (SAW) is reported in this paper. According to the theory of SAW delay line, the effect of temperature and pressure on the sensor can be reflected by variations of the radio frequency (RF) echo signals. The accurate measurement of temperature and pressure can be achieved by introducing a weight factor in the data process. Test results in certain ranges of pressure and temperature demonstrate that the sensor is able to measure temperature (0-200 kPa) and pressure (20-100 ℃) at the same time. For SAW sensors the temperature measurement accuracy can reach 0.05 ℃ and the pressure measurement accuracy can reach 7.2 kPa. In TPMS, where reliability and durability are really demanding, the reported sensor has its practicability and potential market with its advantages of simple structure, and wireless and passive working mode.