Compact dual‐mode bandpass filter using slotline resonator and stubs

Abstract

A compact elliptic‐function‐response bandpass filter using slotline resonators and stubs is designed in this letter. This slotline resonator is composed by one loop resonator with four corner‐patch perturbation and stubs. The nature of coupling between the degenerate modes is investigated with respect to the perturbation size. Also, slotline stubs are applied to miniature the filter's size by keeping excellent performance. Results verify that the central frequency and the fractional bandwidth of the proposed filter are 5.23 GHz and 7.45%, respectively. A good agreement between simulation and measurement verifies the validity of this design methodology. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:641–644, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26603

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