Tunable IF Filter using Thin-Film BST Varactors

Sanderson, G.; Cardona, A. H.; Watson, T.C.; Chase, D.; Roy, Manas Kumar; Paricka, J.M.; York, R.A.

doi:10.1109/mwsym.2007.380011

Cited by 12 publications

(6 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A tunable bandstop filter using slotted ground resonators has been reported in , the device can tune its stopband bandwidth from 1.2 to 1.4 GHz. The lumped element tunable filter in (Sanderson et al, 2007) was designed to tune its center frequency from 31.5 MHz to 88 MHz with a 3 MHz bandwidth; the device uses 8 ferroelectric varactors.…”

Section: Bstmentioning

confidence: 99%

Reconfigurable Microwave Filters

Llamas-Garro¹,

Brito‐Brito²

2010

Microwave and Millimeter Wave Technologies From Photonic Bandgap Devices to Antenna and Applications

View full text Add to dashboard Cite

Section: Bstmentioning

confidence: 99%

Reconfigurable Microwave Filters

Llamas-Garro¹,

Brito‐Brito²

2010

Microwave and Millimeter Wave Technologies From Photonic Bandgap Devices to Antenna and Applications

View full text Add to dashboard Cite

“…Because of their relatively high tunability, low cost, and compact size, tunable capacitors based on thin‐film ferro‐electrics have been studied for various reconfigurable microwave applications [1–4]. Varied tunable passive components and circuits such as filters, matching networks, and phase shifters using ferro‐ and para‐electric materials have been developed.…”

Section: Introductionmentioning

confidence: 99%

A novel low‐voltage tunable capacitor for tunable RF circuit applications

Lee

2013

Micro & Optical Tech Letters

View full text Add to dashboard Cite

Butterworth Hi-Lo LPF in order to achieve 47.7 to 53 dB attenuation at pole frequency 3.3 -3.0 GHz. Likewise, we need 11-pole classical LPF to achieve 68.7 dB attenuation at 5.1 GHz. The present LPF design provides very compact LPF in terms of order of poles. CONCLUSIONWe reported in this article a 5-pole Butterworth TR-LPF to achieve the attenuation performance of 30-pole classical Hi-Lo LPF. The design is very flexible and a designer can obtain desired compromise between sharpness of cut-off and rejection bandwidth, without changing the order of filter, just by selecting the appropriate pole frequency of a filter. We have obtained 53 dB attenuation for the 5-pole TR-LPF. We have also found in EM-Simulator [9] that the attenuation can be further increased to 72 dB for a 7-pole LPF and 94 dB for an 11-pole LPF. In case of the 11-pole LPF at f c ¼ 2.5 GHz, we can achieve more than 7.1 GHz rejection bandwidth at 70 dB rejection. Such performance is normally obtained with bulky waveguide type LPFs.ABSTRACT: In this article, a novel architecture of the tunable capacitor is proposed for low-voltage applications. In order to reduce operation voltage by enhancing fringing electric fields, two finger-patterned electrodes with zero spacing are vertically separated by employing a multilayer thin-film dielectric of a para-/ferro-/paraelectrics. The proposed tunable capacitor was fabricated on a quartz wafer and its characteristics are analyzed in terms of effective capacitance and tunability with a function of applied voltages, in comparison with the tunable capacitor with the finger-pattern electrode only on the top of the dielectric. At 8 V and 2 GHz, the proposed tunable capacitor shows a tunability of 18% that is 10.3% higher than that of the compared one.

show abstract

“…Moreover, some examples of ferroelectric-based bandpass filters (BPFs) with good performances have already been reported for the MHz region, all of them based on localized element BST varactors [7][8][9]. In the case of microwave frequency applications, performances in terms of frequency tunability and insertion loss are still not satisfactory.…”

Section: Introductionmentioning

confidence: 99%

Fully Distributed Tunable Bandpass Filter Based on Ba0.5Sr0.5TiO3 Thin-Film S

Delprat

et al. 2011

International Journal of Microwave Science and Technology

View full text Add to dashboard Cite

This paper presents simulation and measurement results of fully distributed tunable coplanar bandpass filters (BPFs) with center frequencies around 6 GHz that make use of ferroelectric Barium Strontium Titanate (BaxSr1−xTiO3 or BST-x) thin film as tunable material. The two experimental bandpass filters tested are based on a novel frequency-agile structure composed of cascaded half wavelength slow-wave resonators (2 poles) and three coupled interdigital capacitors (IDCs) optimized for bias voltage application. Devices with gap dimensions of 10 and 3 μm are designed and fabricated with a two-step process on polycrystalline Ba0.5Sr0.5TiO3 thin films deposited on alumina substrate. A frequency tunability of 9% is obtained for the 10 μm gap structure at ±30 V with 7 dB insertion loss (the BST dielectric tunability being 26% with 0.04 loss tangent for this gap size). When the structure gap is reduced to 3 μm the center frequency shifts with a constant 9 dB insertion loss from 6.95 GHz at 0 V to 9.05 GHz at ±30 V, thus yielding a filter tunability of 30% (the BST dielectric tunability being 60% with 0.04 loss tangent for this gap size), a performance comparable to some extent to localized or lumped element BPFs operating at microwave frequency (>2 GHz).

show abstract

Tunable IF Filter using Thin-Film BST Varactors

Cited by 12 publications

References 6 publications

Reconfigurable Microwave Filters

Reconfigurable Microwave Filters

A novel low‐voltage tunable capacitor for tunable RF circuit applications

Fully Distributed Tunable Bandpass Filter Based on Ba0.5Sr0.5TiO3 Thin-Film S

Contact Info

Product

Resources

About