摘要
采用开路短路枝节加载开环谐振器,设计了一种新型的3个通带中心频率独立可调的三频带通滤波器.由于谐振器的结构对称,因此采用传统的奇偶模分析法.滤波器的第一和第三通带由偶模谐振频率产生,通过改变加载枝节的电长度和阻抗比可调节偶模谐振频率.滤波器的第二通带由奇模谐振频率产生,通过改变环的电长度和阻抗可调节奇模谐振频率.该滤波器的3个通带中心频率为1.57 GHz(GPS),2.4 GHz(WLAN)和3.5 GHz(WIMAX),3 dB带宽分别为2.5%,4.7%和2.0%,测量结果与电磁仿真结果基本吻合.
A tri-band bandpass filter has been designed using open-loop resonator with open and short stubs.The filter can control each center frequency independently.An odd-even mode analysis is performed on the resonator.The center frequencies of the first and third passbands are obtained with the even mode,and determined by the electrical length and impedance ratio of the stubs.The center frequency of the second passband is obtained with the odd mode and determined by the electrical length and impedance of the open-loop.The filter has triple passband center frequencies of 1.57 GHz for GPS,2.4 GHz for WLAN,and 3.5 GHz for WIMAX,with 3 dB fractional bandwidths of 2.5%,4.7%,and 2.0%,respectively.Measurement results are in general agreement with EM simulation results.
出处
《上海大学学报(自然科学版)》
CAS
CSCD
北大核心
2014年第2期174-179,共6页
Journal of Shanghai University:Natural Science Edition
基金
国家自然科学基金资助项目(61077068
61275070)
上海市重点学科建设资助项目(S30108)
关键词
三频
带通滤波器
奇偶模
开路短路枝节加载
开环谐振器
tri-band
bandpass filter (BPF)
odd-even mode
open and short stubs loaded
open-loop resonator