电介质测量中的谐振腔Q因子特性  

Characterization of the Q-factor of Resonator for Dielectric Measurements

作　　者：倪尔瑚[1] 罗萍[2] 李涤徽[3] 

机构地区：[1]浙江大学材料与化学工程学院,杭州310027 [2]惠州学院电子科学系 [3]中国科学院空间科学与应用研究中心

出　　处：《空间科学学报》2009年第1期73-77,共5页Chinese Journal of Space Science

摘　　要：对同轴线-集中电容负载谐振腔,采用传输测量使用的3dB三频法决定有载Q_l,计及谐振频率下的插入损耗后获得无载Q_u,对同一腔体,也用单端口反射测量技术的xdB三频法,并通过测量回程损耗在谐振点和xdB点的输入反射系数振幅来获得无载Q_u.在500MHz下40个不同的耦合状况下,两种方法得到无载Q_u的算术平均值和标准差为2519±34.这两种技术被用来调节和实现传输型谐振腔的输入、输出的等耦合和电介质测量,本文从介质损耗测量的观点讨论了如何使用有载Q_l和无载Q_u.The transmission-type measurement of the Q-factor of a reentrant cavity is used to determine unloaded Qu from the measured loaded Q1 by the 3 dB three frequencies method together with insertion loss at the maximum output. Also, the one-port reflection technique is used to determine unloaded Qu from the resonant frequency and the bandwidth measured at the x dB point, as well as the magnitudes of the input reflection coefficient measured at both resonant frequency and x dB return loss for the same reentrant cavity. The arithmetic mean Qu was evaluated to be 2519±34 tested under the 40 various couplings at frequency 500 MHz by using transmission and reflection techniques. Finally, these techniques are applied to the realization and tuning of that the input and output couplings are identical to each other for a transmission-mode resonator. Meanwhile, the selection of Q-factor values in measurements of complex permittivity of dielectric materials is discussed.

关 键 词：谐振腔 Q因子测量 电介质测量 

分 类 号：TM934.3[电气工程—电力电子与电力传动]