Design of three‐dimensional filtering balun with inherent complete ground and enhanced stopband rejection. Issue 6 (1st March 2018)

• Record Type: Journal Article
• Authors: Yao, Lidan; Wu, Yongle; Li, Mingxing; Jiao, Lingxiao; Wang, Weimin; Gao, Jinchun; Liu, Yuanan
• Is Part Of: Electronics letters. Volume 54:Issue 6(2018)
• Page Start: 361
• Page End: 363
• Publication Date: 2018-03-01
• Subjects: microwave filters -- baluns -- band‐stop filters -- strip line filters; frequency 3.77 GHz to 9.74 GHz -- 3D filtering balun design -- stopband rejection -- balanced‐to‐unbalanced conversion -- parallel‐strip line filter -- vertically mounted plane -- horizontal feeding plane; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2017.4821
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : A novel design approach of three‐dimensional filtering balun with inherent complete ground and enhanced stopband rejection is proposed. The whole structure consists of a horizontal feeding plane, a vertically mounted plane, and three ports. By arranging the double‐sided parallel‐strip line filter symmetrically on the two sides of the vertical plane, the frequency selectivity and complete ground are effectively synthesised. By inserting a rectangular conductor plane with two crossed slots into the middle of the vertical plane, the balanced‐to‐unbalanced conversion and stopband rejection are significantly enhanced. For demonstration, an experimental filtering balun is fabricated. The measurement agrees well with the simulation, achieving a wide upper stopband under −15 dB from 3.77 to 9.74 GHz.