A novel wireless, passive CO2 sensor incorporating a surface acoustic wave reflective delay line
A novel wireless, passive CO2 sensor incorporating a surface acoustic wave reflective delay line
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DOI：
10.1088/0964-1726/16/4/053
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发表时间：
2007-08-01
影响因子：
4.1
通讯作者：
Yang, Sangsik
中科院分区：
文献类型：
--
作者：
Wang, Wen;Lee, Keekeun;Yang, Sangsik
研制了一种用于CO2检测的440 MHz无线无源声表面波化学传感器。研制的声表面波气体传感器由单相单向换能器（SPUDT）、三个短路光栅反射器和41。YX LiNbO 3衬底。采用模态耦合（COM）建模方法，寻找最佳设计参数。使用提取的设计参数，制作SAW器件。Teflon AF 2400被用作敏感膜，因为它提供了高的CO2溶解性、渗透性和选择性。在使用网络分析仪的无线设备测试中，在时域中观察到具有高信噪比（S/N）、小信号衰减和很少杂散峰的四个尖锐反射峰。反射峰的时间位置与模拟的预测值匹配良好。将CO2注入腔室中引起反射峰的大相移。对于0-450 ppm的CO2浓度，观察到良好的线性和重复性。灵敏度为1.98。ppm（-1）。在灵敏度评价过程中还研究了温度和湿度的影响。
A 440 MHz wireless and passive surface acoustic wave ( SAW) chemical sensor was developed for CO2 detection. The developed SAW gas sensor is composed of single phase unidirectional transducers (SPUDTs), three shorted grating reflectors, and CO2-sensitive polymer film on 41. YX LiNbO3 substrate. Coupling of modes ( COM) modeling was used to find optimal design parameters. Using the extracted design parameters, the SAW device was fabricated. Teflon AF 2400 was used as the sensitive film because it provides high CO2 solubility, permeability and selectivity. In wireless device testing using a network analyzer, four sharp reflection peaks with high signal-to-noise ( S/N) ratio, small signal attenuation, and few spurious peaks were observed in the time domain. The time positions of the reflection peaks were well matched with the predicted values from the simulation. Infusion of CO2 into the chamber induced large phase shifts of the reflection peaks. Good linearity and repeatability were observed for a CO2 concentration of 0-450 ppm. The obtained sensitivity was 1.98. ppm(-1). Temperature and humidity effects were also investigated during the sensitivity evaluation process.