用谐振腔-截止波导技术测量介质谐振器的复介电常数

在TE01n模谐振腔的一个端面中央，开一圆孔，连接一根等直径、适当长度的截止波导，当截止波导中置入介质谐振器时，使含介质段对TE01模呈传输态。介质谐振器的前向波导段用于调节耦合强弱，足够长度的背向波导段则形成匹配电抗终端或置入金属场构成短路终端。这两种安排都能使置入介质谐振器前后的谐振腔产生相当大的谐振长度和Q因子的变化，从而能获得准确的介质谐振器无载Q因子和介电常数。在X频段对陶瓷谐振器进行测量，获得满意的结果。

Measurement of the Dielectric Resonator Complex Permittivity Using Cavity Resonator-Evanescent Waveguide Technique

This paper is concerned to a TE 01n mode resonator coupled through a hole located in the center of the end wall to a waveguide supporting the evanescent TE 01mode.When the evanescent guide contains a dielectric resonator,propagation of TE 01 wave will be permitted in the dielectric filled part.The air filled part in front of the dielectric resonator is used to adjust the coupling level,the air filled part behind the dielectric resonator is used to form a matched reactance termination;otherwise, a metal block is inserted to form a short circuit termination. It is shown that while using these arrangements quite a large change in the resonant length and Q-factor of the cavity resonator will be obtained,when a dielectric resonator is inserted into the evanescent guide.Therefore the accurate values of the complex permittivity for dielectric resonator will be extracted.Fundamental princirples and the experimental restriction are discussed.Measurements for the ceramic resonator are reported also.