基于多段SIR的微带交指滤波器小型化设计
Miniaturized design of microstrip cross-finger filters based on multiband SIR
韩昌霖 1吴建飞 1郑亦菲 1陈乐东 1丁浩1
作者信息
- 1. 国防科技大学电子科学学院 长沙 410000
- 折叠
摘要
微带交指滤波器作为一种常见的二维滤波器,在工程上有着广泛应用,但由于其尺寸较大,从而限制了应用场景的扩展.基于阶跃阻抗谐振器(stepped impedance resona-tor,SIR)理论,设计了一款新型微带交指滤波器,完成了对传统微带交指滤波器的尺寸优化.该滤波器使用三段式SIR结构,与传统结构滤波器的谐振器相比,长度缩减了23.2%.利用CST仿真了相同设计指标下SIR滤波器和传统滤波器的性能,结果表明二者都能够满足设计指标要求,且SIR滤波器在通带内性能更佳,说明使用该方法实现小型化具有较强实用意义.为验证滤波器的可用性,进行了实物加工和测试,谐振结构尺寸为10.9 mm×13.6 mm,为便于测试,电路板尺寸为24 mm×18 mm×0.508 mm,实测结果与仿真结果在通带内最大差异小于1.5 dB.该滤波器的最终指标为中心频率2.5 GHz,带宽150 MHz,带内损耗≤4 dB,阻带抑制≥23 dB(频率≤2.2 GHz或≥2.72 GHz).
Abstract
Microstrip cross-finger filters,as a common two-dimensional filter,have a wide range of engineering applications,but due to their large size,thus limiting the expansion of application scenarios.In this paper,a new microstrip cross-finger filter is designed based on the theory of step impedance resonator(SIR),which completes the optimization of the size of the conventional microstrip cross-finger filter.The filter uses a three-section SIR structure,which reduces the length by 23.2%compared to the resonator of a conventionally structured filter.The performance of SIR filter and traditional filter under the same design index is simulated using CST,and the results show that both of them can meet the design index requirements,and the performance of SIR filter is better in the passband,which indicates that the use of this method to realize the miniaturization has strong practical significance.In order to verify the usability of the filter,physical processing and testing were carried out with a board size of 24 mm×18 mm×0.508 mm,and resonant structure size of 10.9 mm×13.6 mm,the measured results and the simulation results show that the difference between the measured and simulated results is less than 1.5 dB at the passband.The final specifications of this filter are center frequency 2.5 GHz,bandwidth 150 MHz,in-band loss≤4 dB,and stopband rejection≥24 dB(frequency≤2.2 GHz or≥2.72 GHz).
关键词
多段SIR/微带线/带通滤波器/交指结构/小型化Key words
multiband SIR/microstrip line/bandpass filter/cross-finger structure/miniaturization引用本文复制引用
基金项目
国家自然科学基金青年基金(62104255)
国防科技大学校科研项目(ZK21-21)
出版年
2024
NETL
NSTL
万方数据