华南理工大学学报(自然科学版) ›› 2010, Vol. 38 ›› Issue (10): 14-18,23.doi: 10.3969/j.issn.1000-565X.2010.10.003

• 电子、通信与自动控制 • 上一篇    下一篇

具有4个传输零点的源-负载耦合滤波器

褚庆昕 范莉   

  1. 华南理工大学 电子与信息学院, 广东 广州 510640
  • 收稿日期:2010-03-24 修回日期:2010-04-06 出版日期:2010-10-25 发布日期:2010-10-25
  • 通信作者: 褚庆昕(1958-),男,教授,博士生导师,主要从事射频电路与天线研究. E-mail:qxchu@scut.edu.cn
  • 作者简介:褚庆昕(1958-),男,教授,博士生导师,主要从事射频电路与天线研究.
  • 基金资助:

    NSFC-广东省自然科学联合基金资助项目(U0635004); 广东省自然科学基金资助项目(60571056)

Source-Load Coupling Filter with Four Transmission Zero Points

Chu Qing-xin  Fan Li   

  1. School of Electronic and Information Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2010-03-24 Revised:2010-04-06 Online:2010-10-25 Published:2010-10-25
  • Contact: 褚庆昕(1958-),男,教授,博士生导师,主要从事射频电路与天线研究. E-mail:qxchu@scut.edu.cn
  • About author:褚庆昕(1958-),男,教授,博士生导师,主要从事射频电路与天线研究.
  • Supported by:

    NSFC-广东省自然科学联合基金资助项目(U0635004); 广东省自然科学基金资助项目(60571056)

摘要: 为了得到高选择性、小尺寸、低损耗和低成本的射频带通滤波器,提出了一种具有4个传输零点的源负载耦合滤波器的设计方法.该滤波器采用二分之一波长T形多模谐振器,以减小滤波器尺寸和方便带宽设计.同时,根据信号的多路径传输产生零点原理,在滤波器的输入和输出端口之间加入可控耦合元件,为信号的传输提供多条路径,使得该滤波器可产生4个独立于带宽和中心频率的可控零点.文中最后设计和制作了一个带内最小测量插损为1.4 dB、相对带宽为10%、具有4个传输零点的小型微带滤波器,并对其进行了测试,测试结果与仿真结果吻合良好,说明这种设计方法是有效的.

关键词: 带通滤波器, 源-负载耦合, T形谐振器, 传输零点, 耦合电容, 耦合线

Abstract:

In order to obtain bandpass filters with high selectivity,small size,low loss and low cost,a compact source-load coupling filter with four transmission zero points is presented,which uses a half-wavelength multi-mode T-shaped resonator to reduce the filter size and to facilitate the bandwidth design.Then,based on the generation mechanism of transmission zero points,a controllable coupled element is inserted in the region between the input and the output ports to generate multiple paths for signal transmission.Thus,four controllable zero points independent of bandwidth and central efficiency are generated.Moreover,a compact microstrip bandpass filter with four transmission zero points is designed and fabricated,with the insertion loss and the bandwidth respectively reaching 1.4 dB and 10%.Finally,the filter is tested and the results accord well with the simulated ones.It is thus concluded that the proposed design method is feasible.

Key words: bandpass filter, source-load coupling, T-shaped resonator, transmission zero point, coupling capacitor, coupling line