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This paper demonstrates application of the popular stepped-impedance technique to control the bandwidths of dual-band filters independently. Unlike previous dual-band stepped-impedance filters, the role of the stepped-impedance technique is to control the bandwidths of the two bands rather than to provide dual-band performance. The exact relationship(More)
This paper demonstrates extremely miniaturized bandpass filters based on asymmetric coupled lines and equal reactance. By reactively loading asymmetric coupled lines while the first and the last inverters are eliminated, the proposed method overcomes the limitation of previous methods to achieve extreme miniaturization. Furthermore, the utilization of(More)
An accurate design method is proposed for directivity enhancement of microstrip directional couplers loaded with shunt inductors. The parasitic effects of junction discontinuities in various parts of such microstrip directional couplers have critical effects especially on the directivity, and therefore they must be taken into account. Without proper(More)
This paper presents the large-signal performance of intrinsically switchable ferroelectric thin-film bulk acoustic resonators (FBARs), as well as their modeling procedure. There has been a growing interest in ferroelectric FBARs due to their electric-field-dependent permittivity and electric-field-induced piezoelectricity. Ferroelectric(More)
This paper presents a generalized miniaturization method for coupled-line bandpass filters by reactive loading, including the series-inductive loading method that is proposed in this work. It is shown that bandwidth reduction seen in the previous miniaturization method of shunt-capacitive loading is a special case. In fact, one can choose a coupled-line(More)
The large signal modeling procedure for intrinsically switchable film bulk acoustic resonators (FBARs) based on thin film barium strontium titanate (BST) is presented. Thin film BST exhibits electric field dependent permittivity and electric field induced piezoelectricity. In this paper, a large signal model which accurately describes the DC bias voltage as(More)
TRF2 is a ubiquitous protein that protects telomeres in the nucleus. We found that TRF2 was present at the peripheral nerve axons and the brain neuroglial cell processes extensively. It was in the cytoplasmic membrane as well as nuclear fractions, but not in the soluble cytoplasmic fraction of SH-SY5Y neuroblastoma cells. TRF2 was up-regulated in P19(More)
In this paper, a method for extracting the nonlinear mBVD model parameters for intrinsically switchable ferroelectric thin film bulk acoustic resonators (FBARs) is presented. Ferroelectric FBARs based on BST exhibit an electric field induced piezoelectric effect. This property allows for the design of ferroelectric FBAR based tunable and switchable(More)
ii To God To my father Siyoung Choi, and my mother Jaenam Jeon To my fiancé Saebom Jung iii ACKNOWLEDGEMENTS First and foremost, I would like to deeply thank and dedicate all my success to God, my parents, sister, and fiancé. Without their love and care, I would not be able to accomplish my ph.D work. I want to express my sincere gratitude and appreciation(More)
This paper presents the design, simulation results, and measurement results of lateral mode intrinsically switchable bulk acoustic wave resonators based on the ferroelectric material barium titanate. Lateral dimensions of these devices determine their resonance frequencies, significantly simplifying the fabrication of monolithic multi-frequency circuits. By(More)
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