volume | PIER Journals

Abstract

A novel tunable dual-band bandpass filter (DBPF) with high selectivity and independently tunable passbands is proposed in this paper. Electric and magnetic coupling is employed in this design to create transmission zeros. The proposed tunable DBPF has the advantage of fully independent and controllable passbands due to the multipath propagation mechanism. The measured results of tunable DBPF show that the center frequency of the first passband can be shifted from 2.34 to 2.45 GHz when the bias voltage VL increases from 3 V to 15 V, and the second passband can be tuned from 4.73 to 5.04 GHz when the bias voltage VH varies from 6 V to 15 V. Moreover, the core circuit-size of the tunable DBPF is about 0.293 λ_g x 0.067 λ_g, where λ_g is the guided wavelength at 2.4 GHz. The proposed filter exhibits the merits of fully independent and tunable passbands, high selectivity, and compact size.

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Dr. Yue-Peng Zhong

Dr. Yang Xiong

Dr. Jian Huang