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IEEE Microwave and Guided Wave Letters
Volume 10 Number 12, December 2000

New Compact Bandpass Filter Using Microstrip /4 Resonators with Open Stub Inverter

Page 526.

Abstract:

In this letter, a novel bandpass filter using microstrip quarter-wavelength resonators is proposed. The proposed filter consists of the open stub inverter between quarter-wavelength resonators, which results in compact design as well as low loss. The tapped open stub not only works as a K-inverter but also introduces an attenuation pole. The attenuation pole can be located at upper or lower side of the passband by adjusting the open stub length. Two-pole Chebyshev bandpass filter is designed and tested at 1.99 GHz. Four-pole bandpass filter of elliptic-type performance is also designed and tested at 2.015 GHz.

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