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IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 12, December 2000

Table of Contents for this issue

Complete paper in PDF format

New Cross-Coupled Filter Design Using Improved Hairpin Resonators

Sheng-Yuan Lee, Student Member, IEEE and Chih-Ming Tsai Member, IEEE

Page 2482.

Abstract:

Stepped-impedance resonators have been thoroughly studied in this paper. Two equations for odd-and even-mode resonance are derived from a new network model. The size and resonant frequencies of the resonator could then be designed based on these two equations. A new resonator-embedded cross-coupled filter, constructed by stepped-impedance hairpin resonators and miniaturized hairpin resonators, is presented. This new filter is very compact and has lower spurious response. A 0° feed structure, which adds two transmission zeros to the filter response, is also studied. The two zeros are so close to the passband that the selectivity and out-of-band rejection of the filter are significantly increased. The design has been verified by experiment results.

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