基于混合梳状线谐振器的三阶恒定带宽电调微带滤波器研究  

Three-Pole Tunable Filters With Constant Bandwidth Using Mixed Combline and Quasi-Combline Resonators

作　　者：赵志远[1] 杨霖 陈昆和 周强 陈剑斌 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007 [2]南京电讯技术研究所,江苏南京210007

出　　处：《电子学报》2015年第1期140-144,共5页Acta Electronica Sinica

基　　金：中国博士后科学基金(No.2013M532239)

摘　　要：文章提出了一种基于终端加载变容管的混合型梳状线谐振器的三阶电调微带带通滤波器,仅采用两个电压源进行控制.根据奇偶模分析方法,推导了混合梳状线谐振器间耦合系数计算公式,通过合理设计级间及输入输出耦合结构,绝对带宽保持恒定的要求可以得到满足.设计了一个调谐范围为1.0GHz^1.78GHz,3d B绝对带宽为104.5±8MHz的三阶电调滤波器,其插入损耗小于5.7d B,回波损耗优于16d B,对二次谐波的抑制达到60d B.实验结果表明,测试结果与电磁仿真结果基本一致.In this paper,a novel three-pole varactor-tuned bandpass filter using mixed microstrip combline and quasicombline resonators biased by only tw o voltages is proposed. The couplings betw een mixed combline resonators can be controlled so that the constant bandw idth requirement could be satisfied,and the design theory is analyzed based on odd- and even- mode method in detail. The tunable filter has an almost constant 3-d B absolute bandw idth of 104. 5 ± 8M Hz from1. 0GHz to 1. 78 GHz. Its insertion loss varies from 5. 7 d B to 4. 2 d B w ith its return loss better than 16 d B. By using dissimilar resonators,the rejection level at second harmonic is more than 60 d B. The measured results of the fabricated filter show good agreement w ith the simulated ones.

关 键 词：三阶电调滤波器 微带带通滤波器 混合梳状线谐振器 奇偶模分析 变容管 恒定带宽 

分 类 号：TN713[电子电信—电路与系统]