一腔多模动态扫频法测量生物材料的介电特性  

Testing Dielectric Properties of Biological Material by Dynamic Frequency Sweep Method for Multimode Cavity

作　　者：卢智远[1] 侯建强[1] 韩日霞[1] 陈蕊[1] 牛中奇[1] 

机构地区：[1]西安电子科技大学电子工程学院,陕西西安710071

出　　处：《西南交通大学学报》2013年第3期467-472,共6页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金资助项目(30470429)

摘　　要：物质介电特性的无损检测需要多次测量,而每次测量需要重新调试测试系统,这样就使得测量效率降低而成本增加.本研究依据谐振腔微扰法理论,设计了电磁分离的实验测试系统.在该系统中,选取了TE10p(p取奇数)谐振腔谐振模式,采用一腔多模动态扫频法,对多种树木的介电常数和损耗进行了测量计算.该测量方法在同一时间,可以同时测得树木在3个不同频率下的介电常数和损耗特性,极大地减少了单频多次测量过程中调谐腔体尺寸所引起的误差.用该方法对聚四氟乙烯材料的介电常数反复的测量验证,测量误差均小于1%.The microwave nondestructive testing on dielectric constant of material needs several times to tune cavity system, which leads to low efficiency and high cost. Based on the cavity perturbation theory, an electromagnetic separation test system was designed, in which the TEl0p （p is the odd number） oscillation mode was selected. A dynamic frequency sweep method for multiple oscillation modes in a cavity was proposed to measure the dielectric constant and electromagnetic energy loss for different kinds of trees. This method can simultaneously measure the dielectric constants and loss characteristics at three different frequencies, which greatly reduces the error caused by tuning cavity size in the single-frequency measurements. Repetitive test results on the dielectric constant of the polyhef material with the method have error of lesser than 1%.

关 键 词：微扰法 一腔多模 动态扫描 介电特性检测 

分 类 号：TM931[电气工程—电力电子与电力传动]