- 作者: Ruyen Ro ; Shi-Yuan Chang ; Dale Huipin Lee
- 中文摘要: Propagation characteristics of surface acoustic waves (SAWs) generated by interdigital transducers are functions of electric and acoustic properties of liquid loadings. The SAW liquid sensor is designed to detect variations of propagation characteristics and, furthermore, to recognize liquid loadings. A measurement system, which consists of a vector network analyzer, a personal computer, data acquisition software and auxiliary circuits, for characterizing liquid loadings is developed in this paper. Using the full two-port calibration method and time domain measurement technique, the measured scattering parameters can be used to compute the phase velocity and insertion loss of SAW. The error of the measured phase velocity of SAW for the metal surface is 0.13%. Deionized water and aqueous solutions with different mass concentrations of Potassium Chloride (KCl) are characterized using the measurement system. The relaxation phenomena are observed in the fractional velocity change and transmission coefficient change curves. Results obtained can be used to design SAW chemical and biochemical sensors.
- 英文摘要: --
- 中文關鍵字: surface acoustic wave, phase velocity, insertion loss, liquid sensor, relaxation phenomenon
- 英文關鍵字: --