A simple and effective method for microstrip dual-band filters design

• Published in: IEEE microwave and wireless components letters Vol. 16; no. 5; pp. 246 - 248
• Main Authors: CHEN, Chu-Yu, HSU, Cheng-Ying
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.05.2006; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Band pass filters; Circuit properties; Couplings; Dual band; electric coupling; Electric filters; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Exact sciences and technology; Frequency; Frequency bands; Frequency filters; Joining; magnetic coupling; Magnetic separation; Microstrip filters; Microstrip resonators; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Microwaves; open-loop ring resonators (OLRRs); Optical ring resonators; Oscillators, resonators, synthetizers; Passband; Resonator filters; Resonators; standing wave; Dual-band; Microstrip filters; High performance; Microwave filter; electric coupling; Implementation; Open resonator; Frequency band; Ring resonator; Magnetic coupling; open-loop ring resonators (OLRRs); Open loop; Passband; Standing wave
• ISSN: 1531-1309; 1558-1764
• DOI: 10.1109/LMWC.2006.873584

A new type of novel low loss dual-band microstrip filters using folded open-loop ring resonators (OLRRs) is presented in this letter. Both magnetic and electric coupling structures are implemented to provide high performance passband response. The first passband and second passband of the designed dual-band filter can be easily and accurately shifted to a desired frequency band by adjusting the physical dimensions of OLRRs. Finally, the 2.4-GHz/5.7-GHz and 2.4-GHz/5.2-GHz dual-band filters are illustrated and measured in this letter.