Design of miniaturized bandpass filters using microstrip S-type spiral resonators

摘要

At the frequencies used by current mobile communications, most of the microstrip half-wavelength resonators are too large to realize miniaturized filters. For this reason, very small-sized microstrip spiral resonators and filters have been studied recently. In this paper, the resonant and coupling characteristics of microstrip S-type resonators are obtained first by using an electromagnetic simulator. Then small-sized 4-pole, 8-pole, and 16-pole Chebyshev bandpass filters (BPF) with center frequency f{sub}0=1.93GHz are designed, respectively. The frequency responses of the designed filters satisfy the desired specifications well.