High selectivity wideband filtering crossovers using stub-loaded ring resonators. Issue 7 (2nd May 2016)

• Record Type: Journal Article
• Authors: Zhao, Chaoying; Feng, Wenjie; Che, Wenquan
• Is Part Of: Journal of electromagnetic waves and applications. Volume 30:Issue 7(2016)
• Page Start: 860
• Page End: 870
• Publication Date: 2016-05-02
• Subjects: Microwave crossover -- passive filter -- microwave lines -- coupled lines -- wideband; Electromagnetic waves -- Periodicals; Electromagnetic devices -- Periodicals; 621.3
• DOI: 10.1080/09205071.2016.1159997
• Languages: English
• ISSNs: 0920-5071

Abstract

Abstract: Two high selectivity wideband filtering crossovers using stub-loaded ring resonators are proposed in this paper. Cascaded coupled lines and open stubs are used to generate two/four transmission zeros each near the crossover passbands. In addition, patterned grounded conductor in the ground plane can enlarge the coupling coefficient for the coupled lines with increasing the even-mode characteristic impedance, and the isolated conductor placed inside the slot can decrease the odd-mode characteristic impedance. Two filtering crossovers operated at 2.2 GHz with bandwidths of 27.5% from 1.945 to 2.55 GHz are designed and fabricated. They show good return loss more than 20 dB and nice insertion loss less than 1.7 dB in passband.