摘要
传统的调频式石英晶体传感器工作于液相中时，无法区分引起频率偏移的两种不同效应：质量负载和液体阻尼。通过研究石英晶体串联谐振电路的放大和反馈特性，推导出石英晶体谐振器的振幅变化与其动态阻抗的变化成正比，由此分析了双调制式（调频调幅）石英晶体传感器的基本原理，提出特征阻尼理论来区分液相中的质量负载和液体阻尼效应。结果表明，特征阻尼系数ｋｃ０值与晶体表面的固体和液体性质无关，只与晶体谐振器自身的参数有关，如基频、电极面积等，由液体阻尼引起的频率偏移等于石英晶体振幅变化与特征阻尼系数的比值。
The traditional frequency modulated quartz under liquid phase crystal sensor can not distinguish between the two effects which result in the frequency shift under liquid phase: mass loading and liquid damping. From the characteristics of the amplifier and the feedback loop of the series crystal oscillator circuit, it is derived that the change of the amplitude of the quartz crystal sensor is proportional to the change of its motional resistance. the basic principle of dual modulation (amplitude and frequency modulation) of the quartz crystal sensor is analyzed, and a characteristic damping theory is proposed to distinguish between the effects of mass loading and liquid damping. The theory indicates that the value of the characteristic damping coefficient κ c0 is not related to the properties of the liquid and solid deposited on the quartz crystal, it only depends on the parameters of the quartz crystal resonator, such as fundamental frequency, the area of the electrode. The frequency shift resulted by the liquid damping is equal to the ratio of the amplitude change to the characteristic damping coefficient.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
1996年第10期62-66,共5页
Journal of Tsinghua University(Science and Technology)
基金
国家教委重点科研基金
关键词
液相
石英晶体谐振器
传感器
双调制原理
quartz crystal sensor
mass loading
liquid phase
characteristic damping
