【摘要】 对微波谐振腔微扰法检测基本理论和工作原理进行了论述,给出了含有微量水分介质的等效介电常数的计算式,建立了烟支密度和湿度与谐振腔谐振点的频偏及半功率点带宽的数学表达式,设计了适用于烟支湿度密度连续测量的谐振器及检测系统,可实现烟支湿度密度的在线连续测量。该系统采用TM010谐振模,以扫频法检测谐振腔空腔和有烟支状态下的幅频特性,获得谐振频率、峰值功率及半功率带宽。根据相关数学式得到了烟支的湿度和密度。该检测方法具有快速、连续、分辨力高、无污染和操作安全简便等优点。更多还原

【Abstract】 The work principle and basic theory of microwave resonance cavity perturbation were discussed.The formula of volume proportion of water content in medium was presented.Then the math expression between cigarette humidity and density and frequency off set and half power point bandwidth of resonance point of resonance cavity was established.The resonant cavity and the measuring system applied to on-line measurement were designed.The measuring system of this method is simple.This system adopted the TM010 resonance model.The resonance frequency,peak power and half power point bandwidth can be obtained from amplitude-frequency characteristic detected under the condition of vacuum resonance and cigarette in existence with the swept technique.And some relative mathematical formulas,cigarette humidity and density can be calculated respectively.The detection technique has many advantages such as speediness,continuation,high resolution rate,non-pollution,safe and convenient operation.更多还原