A liquid-loaded frequency tunable cavity bandpass filter (BPF) is presented. A dielectric fluidic material, dimethyl silicone oil (DSO) withexcellent thermophysical characteristics (working temperature from −50 ℃ to ...A liquid-loaded frequency tunable cavity bandpass filter (BPF) is presented. A dielectric fluidic material, dimethyl silicone oil (DSO) withexcellent thermophysical characteristics (working temperature from −50 ℃ to 180 ℃) and extremely low loss tangent is employed as a dielectric loading.The frequency reconfigurability of the proposed design is realized by altering the liquid level inside the cavity resonator. The filter achieves a widefrequency tuning range as well as a high Q factor. Moreover, this design shows significantly improved environmental suitability in extreme temperaturecases, outperforming the existing microfluidic-based RF devices using water or liquid metals. A four-pole tunable cavity bandpass filter is designed andverified. A cross-coupling structure comprising a metal loop structure is used to introduce transmission zeros in the proposed filter, which enhances theskirt selectivity and out-of-band rejections. We demonstrate that the center frequency of the proposed BPF can be tuned from 4.92 GHz to 6.16 GHz,and the filter achieves a high Q factor between 521 and 1527. The measured results agree well with simulated results.展开更多
基金supported in part by the National Defense Basic Scientific Research Program of China(Grant No.JCKYS2021DC05)in part by The Fund of Prospective Layout of Scientific Research for Nanjing University of Aeronautics and Astronautics(NUAA)。
文摘A liquid-loaded frequency tunable cavity bandpass filter (BPF) is presented. A dielectric fluidic material, dimethyl silicone oil (DSO) withexcellent thermophysical characteristics (working temperature from −50 ℃ to 180 ℃) and extremely low loss tangent is employed as a dielectric loading.The frequency reconfigurability of the proposed design is realized by altering the liquid level inside the cavity resonator. The filter achieves a widefrequency tuning range as well as a high Q factor. Moreover, this design shows significantly improved environmental suitability in extreme temperaturecases, outperforming the existing microfluidic-based RF devices using water or liquid metals. A four-pole tunable cavity bandpass filter is designed andverified. A cross-coupling structure comprising a metal loop structure is used to introduce transmission zeros in the proposed filter, which enhances theskirt selectivity and out-of-band rejections. We demonstrate that the center frequency of the proposed BPF can be tuned from 4.92 GHz to 6.16 GHz,and the filter achieves a high Q factor between 521 and 1527. The measured results agree well with simulated results.
