Compact input-reflectionless balanced bandpass filter with flexible bandwidth using three-line coupled structure

作     者：Yahui ZHU Jing CAI Wei QIN Wenwen YANG Jianxin CHEN Yahui ZHU;Jing CAI;Wei QIN;Wenwen YANG;Jianxin CHEN

作者机构：School of Information Science and TechnologyNantong UniversityNantong226019China Research Center for Intelligent Information TechnologyNantong UniversityNantong226019China 

出 版 物：《Frontiers of Information Technology & Electronic Engineering》 (信息与电子工程前沿（英文版）)

年 卷 期：2023年第24卷第2期

页      面：314-326页

核心收录：

学科分类：0808[工学-电气工程] 080902[工学-电路与系统] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0835[工学-软件工程] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：Project supported by the National Natural Science Foundation of China(No.20201438) 

主　　题：Input-reflectionless filter Balanced bandpass filter(BPF) Differential mode(DM) Common mode(CM) Three-line coupled structure(TLCS) 

摘      要：A compact input-reflectionless balanced bandpass filter(BPF)with flexible bandwidth(BW)using a three-line coupled structure(TLCS)is presented in this *** the differential mode(DM),the TLCS is applied to achieve the bandpass response;meanwhile,the input coupled-feed line of the TLCS is reused in the input absorption *** design shows a good fusion of the absorptive and BPF sections,effectively reducing the circuit size,and the BWs of the two sections that can be controlled separately result in a flexibly controllable DM response BW of the proposed input-reflectionless balanced *** analyses of the ratio of the two-part BWs have been given for the first time,which is vital for the passband flatness and reflectionless *** the codesign of this work,the input-reflectionless DM bandpass response can be optimized easily,while wideband common mode(CM)noise absorption is achieved by the input absorption *** verify the design method,a prototype with a compact layout(0.52λ×0.36λ)is designed and measured in the 0-7.0 GHz *** DM center frequency(f0)is 2.45 GHz with a measured 3 dB fractional bandwidth of 31.4%.The simulation and measurement results with good agreement are presented,showing good performance,e.g.,low insertion loss(0.43 dB),wide upper stopband for the DM bandpass response(over 20 dB rejection level up to 2.72f0),and wideband DM reflectionless and CM noise absorption(fractional absorption bandwidth of 285.7%).