The Study of the High Frequency Acoustic Wave Oscillator and Applications

• Main Authors: chia-song chiu, 邱佳松
• Other Authors: Erik S. Jeng
• Format: Others
• Language: en_US
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/39288794179301306741

碩士 === 中原大學 === 電子工程研究所 === 90 === Piezoelectric resonators have been widely used as sensors for mass, temperature, stress and many other fields. Quartz resonators using surface acoustic wave (SAW) modes have been the most extensively used in mass sensing devices. SAW devices coated with polymer as chemical sensors become popular in the detection of a variety of organic gases. This thesis presents a Pierce-type oscillator using two-port SAW devices. The center frequency and the insertion loss of SAW device are 157.7MHz and —19.78dB respectively. The output power of oscillator using SAW device is 16dBm@157.326MHz while its phase noise is -62.6dBc/Hz@100KHz. SAW ocillators with organic films using C2H2 and C2H2/N2 to detect the serveral organic vapors. Results were obtained and discussed with SAW devices for the organic gas detection. The oscillator devices have been shown to be potential for an robust and handy gas detections.