Results 11 to 20 of about 181,882 (261)
AC amplifiers with ultra‐low corner frequency by using bootstrapping
Electronics Letters, 2021 A novel architecture for an AC (i.e. high‐pass) amplifier is proposed allowing a drastic reduction of the cutoff frequency to the sub‐Hertz range. It builds upon the classic AC configuration with a high gain amplifier and a parallel RC circuit in the ...
Maite Martincorena‐Arraiza +3 more
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The occurrence mechanism and damping method of ultra‐low‐frequency oscillations
IET Renewable Power Generation, 2021 The ultra‐low‐frequency oscillation (ULFO) problem has reappeared in China recently. Although the hydraulic generator is supposed to have a strong connection to this problem, the conditions for ULFO appearance and detailed reasons are not clear yet.
Peng Wang +6 more
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Design of a Clinical Ultra-Low Frequency Ballistocardiograph [PDF]
Circulation, 1959 The potential advantages of an ultra-low frequency ballistocardiograph are presented.
R R, DONALDSON +3 more
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A family of AC amplifiers for ultra‐low frequency operation [PDF]
International Journal of Circuit Theory and Applications, 2021 AbstractA family of capacitively coupled alternating current (AC) amplifiers featuring ultra‐low (below 1 Hz) corner frequency is presented. This is achieved by using high‐gain devices which actively boost feedback resistance and thus reduce corner frequency.
Maite Martincorena-Arraiza +4 more
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Design of a LNA for ULF wireless communication
Dianzi Jishu Yingyong, 2021 This paper introduces the design of low noise amplifier, using for ultra-low frequency. There′s a new loop in the paper, formed by a low-pass transconductance and a self-cascode MOSFET, proposed to stabilize the output bias voltage of the amplifier.
Zhang Mengwen, Jin Yufeng
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Radial Gradient Seismic Metamaterials with Ultra-Low Frequency and Ultra-Wide Band Gap
Applied Sciences, 2023 In this paper, a radial gradient seismic metamaterial (RGSM) is proposed. The structural unit cell is composed of an external square soil embedded with a triangular-cross-sectioned steel ring, which is filled at different angles of multiple steel rings ...
Qian Yang +4 more
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Ultra-Low-Frequency Acoustic Black Hole Radial Elastic Metamaterials
Applied Sciences, 2023 In this paper, we propose an acoustic black hole radial elastic metamaterial (AREM). Through the study of its dispersion relations, it is found that, compared with the conventional elastic metamaterial, the AREM gathers energy at the tip of the black ...
Lixia Li, Haiteng Hu, Xiaolan Wu
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Tidal modulation of very-low-frequency and ultra-low-frequency ambient noise levels
JASA Express Letters, 2023 Several years of continuous low-frequency underwater ambient noise data from 0.1 to 125 Hz have been made available for examination by the United Nations Comprehensive Nuclear Test Ban Treaty Organization. Narrow-band noise time records between 0.5 and 10 Hz were selected for study, chosen deliberately to address noise sources tied primarily to the ...
Anthony I, Eller +2 more
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ULTRA LOW FREQUENCY EMISSIONS RANGING FROM 0.1 TO 3 Hz IN CIRCUMPOLAR AREAS
Solar-Terrestrial Physics, 2020 We examine the characteristics of oscillations of two types in the high-frequency edge of the ULF range (0.1–3 Hz), serpentine emission (SE), and discrete frequency dispersed signals (DS).
A.S. Potapov +2 more
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A low complexity digital frequency calibration with high jitter immunity for ultra-low-power oscillators [PDF]
Advances in Radio Science, 2019 This paper presents a highly efficient digital frequency calibration method for ultra-low-power oscillators in wireless communication systems. This calibration method locks the ultra-low-power oscillator's output frequency to the reference clock of the ...
M. Scholl, R. Wunderlich, S. Heinen
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