短路枝节加载微带传输线滤波器设计方法研究
Design method for short-circuited stubs loaded microstrip transmission-line bandpass filter
刘远志 1杨秀强1
作者信息
- 1. 中国电科集团第二十九研究所成都西科微波通讯有限公司,四川成都 610091
- 折叠
摘要
对于微带线滤波器为代表的传输线滤波器设计,给定技术指标,如何快速准确地确定其拓扑结构和结构参数是其中的关键.由于分布参数效应,导致传输线滤波器设计比较困难.针对一种短路枝节加载微带传输线滤波器,深入研究了其物理机制,给出了解析设计方法.首先导出了滤波器的传输矩阵,接着通过cot变换关系对传输矩阵进行变换,最后将其与根据技术指标综合得到的理想传输矩阵进行比对,从而能够快速地确定滤波器的结构参数初始值.为了验证所述设计方法,设计了一个中心频率为3.0 GHz,绝对带宽为2.0 GHz,回波损耗小于-20 dB的三阶带通滤波器实例,并进行了加工测试.测试结果表明,理论、仿真和测试结果相吻合,验证了设计方法的有效性.
Abstract
For transmission-line filters such as the microstrip filters,it is key to fast determine their topologies and structural parameters when the technical specifications are given.However,the design of transmission-line filters becomes very challenging due to the distributed-element effect.A kind of the shorted-circuited stubs loaded microstrip transmission-line filters was investigated,the physical mechanism was discussed,and the design method was developed.At first,the transmission matrix of the filter was derived.The cot transformation was applied,and then the ideal transmission matrix was synthesized theoretically and compared with the former.So the structural parameters of the filter could be calculated.In order to verify the proposed design method,a third-order bandpass filter example was designed,fabricated and measured.The center frequency of it is 3.0 GHz,the bandwidth is 2.0 GHz,and the in-band return loss is lower than-20 dB.The measured results show that the theory,simulation and test results are consistent,so that the proposed design method is verified.
关键词
短路枝节加载/微带传输线滤波器/设计方法/带通滤波器/传输矩阵/cot变换Key words
shorted-circuited stubs loaded/microstrip transmission-line filter/design method/bandpass filter/transmission matrix/cot transformation引用本文复制引用
基金项目
四川省关键核心技术自主可控攻关项目(000018)
出版年
2024
国家科技期刊平台
NSTL
万方数据