A Passive UHF RFID Dielectric Sensor for Aqueous Electrolytes
A Passive UHF RFID Dielectric Sensor for Aqueous Electrolytes
复制标题
DOI：
10.1109/jsen.2019.2909353
复制
发表时间：
2019-07-15
影响因子：
4.3
通讯作者：
Batchelor, John C.
中科院分区：
文献类型：
--
作者：
Hillier, Aaron J. R.;Makarovaite, Viktorija;Batchelor, John C.
使用基于聚二甲基硅氧烷的薄膜化学方法对商用RFID传感标签进行了一步修改，构建了可重复使用的无源RFID传感器，用于电解质溶液的介电性质随浓度的变化。PDMS膜厚度的影响被表征为RFID传感器代码值的函数。RFMicron RFM2100-AER无线柔性水分传感器的输出传感器代码(在800至860 MHz之间采集)与标签干燥和标签在传感器区域有水沉积时的读数进行了比较。直接在标签上应用液态水的效果是改变提供给集成芯片的电容，该芯片可以自动调整以校正电抗。通过改变交叉型传感器和沉积液之间的PDMS膜的厚度，可以控制标签对高介电介质的灵敏度。水盐溶液在500亩m厚的薄膜上进行测试。研究发现，该传感平台可用于测量0-2M范围内各种盐溶液的浓度，并可作为无源超高频射频识别介电测量工具。随后使用较小的频率范围(845-865 MHz)演示了该平台的测量能力。
The one-step modification of a commercial RFID sensing tag is demonstrated using polydimethylsiloxane-based thin-film chemistry to construct reusable passive RFID sensors for changes in the dielectric properties of electrolyte solutions as a function of concentration. The effects of PDMS film thickness were characterized as a function of RFID sensor code value. The output sensor code of the RFMicron RFM2100-AER wireless flexible moisture sensor (taken between 800 and 860 MHz) was compared with the readings taken when the tag was dry and when the tag had a water deposition on the sensor area. The effect of the direct application of liquid water on the tag was to alter the capacitance presented to the integrated chip which auto-tunes to correct for the reactance. By varying the thickness of the PDMS film between the interdigitated sensor and deposited liquid, the sensitivity of the tag to a high dielectric medium could be controlled. Aqueous salt solutions were tested on a 500 mu m-thick film. It was found that the sensing platform could be used as a means of measuring the concentration of various salt solutions within the range 0-2 M and in turn could be used as a passive UHF RFID dielectric measuring tool. The measurement capability of the platform was subsequently demonstrated using a reduced frequency range (845-865 MHz).