volume | PIER Journals

Abstract

This paper proposes asymmetrical step-impedance resonators bandpass filters (ASIRs) for suppressing a wide stopband, ensuing in size reduction and ease of fabrication. The filters have been designed at the operating frequency around 2.0 GHz using half- and quarter-wavelength asymmetrical step-impedance resonators. The concept of existent odd- and even-mode characteristics is used to approve the proposed filter structure. The filter can not only suppress the unwanted signals more than 10 f₀, but also produce low passband insertion loss and high return loss. A good agreement is obtained between the simulation and measurement results.

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Dr. Apirada Namsang

Professor Prayoot Akkaraekthalin