Dual-Band Bandpass Filters Using Stub-Loaded Resonators

• Published in: IEEE microwave and wireless components letters Vol. 17; no. 8; pp. 583 - 585
• Main Authors: Zhang, Xiu Yin, Chen, Jian-Xin, Xue, Quan, Li, Si-Min
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.08.2007; Institute of Electrical and Electronics Engineers
• Subjects: Admittance; Analytical models; Applied sciences; Band pass filters; Bandpass filter (BPF); Bandpass filters; Circuit properties; Design engineering; Dual band; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Equivalent circuits; Exact sciences and technology; Filtering theory; Frequency filters; Microstrip resonators; Microwaves; Oscillators, resonators, synthetizers; Passband; Resonant frequencies; Resonant frequency; Resonator filters; Resonators; Selectivity; Simulation; stub-loaded resonator (SLR); Bandpass filter (BPF); Resonator; dual-band; Simulation; Resonance frequency; Band pass filter; Selectivity; Passband; stub-loaded resonator (SLR); Implementation
• ISSN: 1531-1309
• DOI: 10.1109/LMWC.2007.901768

Dual-band bandpass filters using novel stub-loaded resonators (SLRs) are presented in this letter. Characterized by both theoretical analysis and full-wave simulation, the proposed SLR is found to have the advantage that the even-mode resonant frequencies can be flexibly controlled whereas the odd-mode resonant frequencies are fixed. Based on the proposed SLR, a dual-band filter is implemented with three transmission zeros. To further improve the selectivity, a filter with four transmission zeros on either side of both passbands is designed by introducing spur-line. The measured results validate the proposed design.