基于阶跃阻抗谐振器的耦合微带带通滤波器设计

基于阶跃阻抗谐振器的耦合微带带通滤波器设计

内容简介：针对寄生通带降低了耦合微带带通滤波器选择性的问题，设计了1／4波长型阶跃阻抗谐振器（SIR）的微带带通滤波器．以平行耦合微带线为基础。从上层微带线结构着手，对SIR的谐振特性和设计参量进行了推导，根据微带带通滤波器的设计指标，在馈线端端接相应的SIR谐振结构。使带通滤波器在寄生通带处的衰减达到了．45dB，提高了带通滤波器的选择性．采用插入损耗和网络综合的方法，利用ADs仿真工具对该滤波器进行优化仿真设计。结果表明。基于SIR结构的滤波器克服了寄生通带对设计通带的影响，提高了滤波器的带外抑制能力．

Abstract：In the process of designing coupled microstrip bandpass filter, the parasitic bandpass reduces the filter＇s selectivity. The study designed a microstrip bandpass filter with 1 / 4 wavelength type of step-impedance resonator （SIR） based on parallel coupled microstrip lines. The study began with the upper microstrip line structure and deduced the SIR＇s resonant characteristics and design parameters. According to the design index of the microstrip bandpass filter, corresponding SIR resonant structure was added on the feeder end to make the attenuation in parasitic bandpass reach -45 dB and improve the band-pass filter selectivity. The study adopted the methods of Insertion Loss and Comprehensive Network and used ADS to simulate and optimize design. The simulation results showed that the filter based on the structure of the SIR overcame the influence of parasitic bandpass and improved the filter＇s out-of-band inhibitory ability.

作者：徐利, 廖惜春, 陈婷婷,

关键词：无线通信, 微带滤波器, 寄生通带, 阶跃阻抗谐振器