Title :
Quasi-Elliptic Wideband Bandstop Filter Using Stepped-Impedance Coupled Line
Author :
Si-Wei Ren ; Lin-Sheng Wu ; Hong-Li Peng ; Jun-Fa Mao
Author_Institution :
Key Lab. of Minist. of Educ. of Design & Electromagn. Compatibility of High-Speed Electron. Syst., Shanghai Jiao Tong Univ., Shanghai, China
Abstract :
A cross-coupled wideband bandstop filter (BSF) with a 5th-order quasi-elliptic response is proposed and investigated in this letter. The BSF is composed of stepped-impedance coupled line connected by an open-circuited shunt stub. An enhanced selectivity and stopband rejection can be achieved as a result of two new transmission zeros, generated from the stepped-impedance coupled line. Based on the derived rigorous correspondence between the BSF and its lumped prototype, design of the proposed BSF can be handled as the same to the lumped network. A BSF example is given with measured stopband attenuation of 34.4 dB over a fractional bandwidth of 113.4%.
Keywords :
band-stop filters; coupled transmission lines; electric impedance; poles and zeros; 5th-order quasielliptic response; BSF; cross-coupled wideband bandstop filter; lumped network; open-circuited shunt stub; quasielliptic wideband bandstop filter; stepped-impedance coupled line; stopband rejection; transmission zeros; Attenuation; Filtering theory; Microstrip; Passband; Prototypes; Wideband; Wireless communication; Bandstop filter (BSF); cross coupling; quasi-elliptic; wideband;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2015.2421343
