基于微带-槽线结构的宽带反相滤波功分器综合设计  

Integrated Design of Broadband Out-of-phase Filtering Power Divider Based on Microstrip-slot Line Structure

作　　者：王雪道 殷燕 WANG Xue-dao;YIN Yan(Jinling Institute of Technology,Nanjing 211169,China;Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]金陵科技学院电子信息工程学院,江苏南京211169 [2]南京理工大学电子工程与光电技术学院,江苏南京210094

出　　处：《金陵科技学院学报》2022年第4期58-66,共9页Journal of Jinling Institute of Technology

基　　金：国家自然科学基金青年项目(62101224);江苏省自然科学基金青年项目(BK20210004);金陵科技学院高层次人才科研启动基金(jit-b-202152)。

摘　　要：针对反相滤波功分器在频率选择、工作带宽及端口隔离等性能上存在的缺陷,提出了一种宽带高选择性反相滤波功分器的设计方法。利用微带-槽线过渡结构,在输入端引入开-短路阶梯阻抗谐振器,产生了2个传输零点,使得反相滤波功分器的频率响应具有陡峭的边缘选择性;利用输出端口对称面上加载的接地电阻,实现了宽带的端口间隔离;通过分析奇模等效电路的特征函数,在理论上给出了二阶和三阶准椭圆滤波响应的必要条件,并且以二阶滤波响应为例,加工并测试了一款中心频率为2.8 GHz的宽带滤波功分器。测试结果表明:该反相滤波功分器的3-dB相对带宽为64.8%,输出端口间的隔离度高于14 dB,适用于宽带无线通信系统。In view of the shortcomings of the out-of-phase filtering power divider in frequency selectivity,operating bandwidth and port-to-port isolation,a design method of wideband and highly selective out-of-phase filtering power divider is proposed.By using the microstrip-slotline transition structure,stepped impedance resonator with open-/short-circuited ends are introduced at the input end to generate two transmission zeros,which makes the frequency response of the out-of-phase filtering power divider have steep edge selectivity.By using a grounded resistor loaded on the symmetrical plane of the output ports,the broadband port-to-port isolation is realized.By analyzing the characteristic function of the odd mode equivalent circuit,necessary conditions for the second-order and third-order quasi elliptic filter responses are designed theoretically.Taking the second-order filter response as an example,a broadband filtering power divider with a center frequency of 2.8 GHz is processed and tested.The test results show that the 3-dB relative bandwidth of the out-of-phase filtering power divider is 64.8%,and the isolation between output ports is higher than 14 dB,which is suitable for broadband wireless communication systems.

关 键 词：滤波功分器 反相 宽带 隔离 阶梯阻抗谐振器 

分 类 号：TN626[电子电信—电路与系统]