Characteristic of 433MHz Surface Acoustic Wave Array for Organic Vapor Recognition

• Main Authors: Yi-Lin Guan, 管懿麟
• Other Authors: Syang-Ywan Jeng
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/bxdx6k

碩士 === 中原大學 === 電子工程研究所 === 106 === Surface acoustic wave (SAW) technology has been widely used in signal processing and communications for many years due to its mature manufacturing technology and low cost (requiring a low number of photomasks). As the same time for the surface acoustic wave sensor with high sensitivity, small components, easy to shrink and so on. It has been widely used in sensing gas, liquid, temperature and humidity, pressure and other different applications. Now surface acoustic wave sensors are active in various mobile and IOT devices as MEMs sensors. This paper is based on the principle of human olfactory system bionics, four kinds of polymer films were sprayed on four array of SAW devices to enhance the selective adsorption capacity of each SAW device, and establish a surface acoustic wave array sensing system. A sensing platform for gas feature interception built by frequency mixer, amplifier and frequency division. Based on the sensing principle of the surface acoustic wave sensor, characteristics are analyzed in accordance with the sensed gas. SAW array uses four kinds of macromolecule films EC(Ethylene Cellulose), PVC(Polyvinylchloride), PVP(Polyvinylpyrrolidone) and PMMA(Polymethylmethacrylate) to detect gas, including four kinds of volatile organic compounds, such as benzene, butanone, methanol and ethanol. In order to investigate the differences in the adsorption of different gases on different membranes, the four kinds of gas sensors were used to standardize the frequency drift of each gas, and create a radar map of the characterization of volatile organic compounds.