传输零点对称可调的调谐滤波器的设计  

Design of a Tuning Filter with a Symmetrically Tunable Transmission Zero

作　　者：杨勇 严君美 YANG Yong;YAN Junmei(School of Mechanical and Electronic Engineering,Jingdezhen Ceramic University,Jingdezhen Jiangxi 333403,China)

机构地区：[1]景德镇陶瓷大学机械电子工程学院,江西景德镇333403

出　　处：《佳木斯大学学报（自然科学版）》2024年第5期80-84,共5页Journal of Jiamusi University：Natural Science Edition

基　　金：国家自然科学基金(61741110,61661023)。

摘　　要：为改善滤波器的带外抑制效果,设计了一款微带平面结构的电调带通滤波器,可以实现滤波器中心频率的调谐和一个传输零点的对称可调。由于采用Doublet型耦合结构,传输零点的对称可调是通过调整谐振器的谐振频率实现的,不需要调整与端口间的耦合系数。采用微带结构,不仅使结构简单,也实现了两个谐振器与端口的耦合系数的单独控制。文中对Doublet型耦合结构进行了详细的研究,总结出了其产生有限位置传输零点的条件和特点。设计采用基于耦合矩阵的设计方法,文中详细描述了设计过程。实际设计、加工并测试了一款滤波器,中心频率调整范围为1,24GHz~1.36GHz,传输零点在左侧的调谐范围为1,225GHz~1.345GHz,右侧为1,225GHz~1.375GHz,回波损耗保持为-20dB左右。测试结果与仿真结果基本吻合,证明了所提滤波器及其设计方法的有效性。To improve the out-of-band rejection performance of the filter,this paper designed a reconfigurable band pass filter based on the micro strip planar structure.This filter could realize tunable central frequencies and a symmetrically tunable transmission zero.Due to use of Doublet-type coupling structure,its symmetrically tunable transmission zero was realized only by adjusting the resonant frequency of the resonators and it was no need to adjust the coupling coefficient.The filter was implemented using the micro strip planar structure,which not only made the filter has a simple scheme,but also could realize the separately controlling of the port couplings.In this paper,the Doublet-type coupling structure was studied in detail and characteristics and conditions of generating the finite transmission zero were summarized.The filter was designed based on the coupling matrix theory.The design procedure was described in detail.A prototype filter is actually designed,fabricated and measured.Its center frequency is tunable during 1,24~1.36GHz.Its left-side transmission zero is during 1,225~1.345GHz and right-side transmission zero isduring1,255~1.375GHz.The return loss of about-20 dB is achieved.The measured results are basically consistent with the simulated ones,which verifies the effectiveness of the proposed filter and the design method.

关 键 词：电调带通滤波器 传输零点 谐振频率 耦合矩阵 

分 类 号：TN713[电子电信—电路与系统]