Title :
A folded coupled-line structure and its application to filter and diplexer design
Author :
Chih-Ming Tsai ; Sheng-Yuan Lee ; Chia-Cheng Chuang ; Chin-Chuan Tsai
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
In this paper, a folded coupled-line structure which can create a transmission zero is studied. A rough estimate for the frequency of this transmission zero is also given. A compact second-order filter with the folded coupled-line structures and a skew-symmetric (zero-degree) feed structure is designed. The improved shape factor and out-of-band response of this new filter are compared with those of a conventional second-order filter. Finally, this new filter topology is applied to the design of a diplexer.
Keywords :
UHF filters; linear network analysis; microstrip components; microstrip filters; multiplexing equipment; passive filters; poles and zeros; 1.5 GHz; 1.7 GHz; 40 MHz; compact second-order filter; diplexer design; folded coupled-line structure; microstrip line; out-of-band response improvement; second-order planar filter; shape factor improvement; skew-symmetric feed structure; transmission zero; zero-degree feed structure; Coupling circuits; Feeds; Filtering theory; Filters; Frequency estimation; Impedance; Microstrip; Passband; Shape; Transmission line matrix methods;
Conference_Titel :
Microwave Symposium Digest, 2002 IEEE MTT-S International
Conference_Location :
Seattle, WA, USA
Print_ISBN :
0-7803-7239-5
DOI :
10.1109/MWSYM.2002.1012241
