Results 121 to 130 of about 56,039 (156)
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Proceedings of the IEEE, 1976
Motion-induced noise can be an overwhelming source of inteference in vector magnetic field sensors designed for submarine communications in the 30-130-Hz portion of the extremely low frequency (ELF) band. In the case of an ELF antenna constructed using three orthogonal superconducting quantum interference devices (SQUID's) as receiving elements, the ...
R.J. Dinger, J.R. Davis
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Motion-induced noise can be an overwhelming source of inteference in vector magnetic field sensors designed for submarine communications in the 30-130-Hz portion of the extremely low frequency (ELF) band. In the case of an ELF antenna constructed using three orthogonal superconducting quantum interference devices (SQUID's) as receiving elements, the ...
R.J. Dinger, J.R. Davis
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Why is sharp-limited low-frequency noise extremely annoying
The Journal of the Acoustical Society of America, 2008Sharp-limited low-frequency noise having only weak components of higher frequencies, such as noise of an air condition or traffic noise attenuated by a thick window, has a very annoying effect on persons also at low levels. The strong fluctuation, which is specific to this kind of sound, is a frequently used explanation for this effect possibly caused ...
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2018 26th European Signal Processing Conference (EUSIPCO), 2018
This contribution is aimed at separating the anthropogenic noise from the natural magnetic field in the measurements recorded in a Extremely Low Frequency band station located in Sierra Nevada, Spain, to experimentally study Schu-mann resonances. First, we use a scheme based on Independent Component Analysis that provides unsatisfactory results.
Jesus Rodriguez-Camacho +4 more
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This contribution is aimed at separating the anthropogenic noise from the natural magnetic field in the measurements recorded in a Extremely Low Frequency band station located in Sierra Nevada, Spain, to experimentally study Schu-mann resonances. First, we use a scheme based on Independent Component Analysis that provides unsatisfactory results.
Jesus Rodriguez-Camacho +4 more
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Design of a Sanguine Noise Processor Based Upon World-Wide Extremely Low Frequency (ELF) Recordings
IEEE Transactions on Communications, 1974This paper describes the design of a candidate noise processor for the Sanguine receiver based on communication theory considerations and detailed experiments using wide-band recordings of extremely low-frequency (ELF) (3-300 Hz) atmospheric noise. This processor consists of the following elements: 1) a compensating (or whitening) filter; 2) nonlinear ...
J. Evans, A. Griffiths
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Extremely Low Frequency (ELF) Atmospheric Noise Level Statistics for Project Sanguine
IEEE Transactions on Communications, 1974Statistics of narrow-band extremely low frequency (ELF) noise for use in Sanguine systems analysis were obtained at locations in Malta and Guam. The results of four seasons of ELF atmospheric noise measurements are discussed. In particular the contributions of local thunderstorms to high noise levels, i.e., the 1 percent exceedance levels, are shown ...
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Radiophysics and Quantum Electronics, 2012
Using the data of continuous monitoring of low-frequency background noise at the station “Novaya Zhizn” (Nizhny Novgorod Province, Russia) for 2006–2010, we studied a new spectral structure appearing in quasi-harmonic oscillations of the noise intensity with frequency scales a factor of 3 to 4 smaller than the scales of an ordinary spectral resonance ...
E. N. Ermakova +2 more
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Using the data of continuous monitoring of low-frequency background noise at the station “Novaya Zhizn” (Nizhny Novgorod Province, Russia) for 2006–2010, we studied a new spectral structure appearing in quasi-harmonic oscillations of the noise intensity with frequency scales a factor of 3 to 4 smaller than the scales of an ordinary spectral resonance ...
E. N. Ermakova +2 more
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49th ARFTG Conference Digest, 1997
Full noise characterization of transistors comprises the experimental determination of minimum noise figure NF,;,, noise resistance R,, and optimum source reflection coefficient magnitude irupaJnd angle L.. The usual commercial and laboratory equipment is mainly designed for the microwave and millimeter-wave frequency range and the performance in the ...
P. Heymann, R. Doerner, H. Prinzler
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Full noise characterization of transistors comprises the experimental determination of minimum noise figure NF,;,, noise resistance R,, and optimum source reflection coefficient magnitude irupaJnd angle L.. The usual commercial and laboratory equipment is mainly designed for the microwave and millimeter-wave frequency range and the performance in the ...
P. Heymann, R. Doerner, H. Prinzler
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Motion-Induced Noise in Electrode-Pair Extremely Low Frequency (ELF) Receiving Antennas
IEEE Transactions on Communications, 1974The pressure fluctuations in the turbulent boundary layer surrounding the towed antenna cable cause it to vibrate in the geomagnetic field and thereby generate noise. This noise mechanism is the dominant one in current long antennas. Its effect can be reduced only by increasing antenna diameter and length. Tension, stiffness, and damping have no effect.
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Journal of Geophysical Research, 1961
Calculations by Raemer of the terrestrial ELF noise spectrum which are based on a sharply bounded homogeneous ionosphere of frequency-dependent height and conductivity are extended to a nonhomogeneous ionosphere of exponential conductivity profile. The exponential ionosphere model provides slightly lower resonant frequencies and less damping of the ...
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Calculations by Raemer of the terrestrial ELF noise spectrum which are based on a sharply bounded homogeneous ionosphere of frequency-dependent height and conductivity are extended to a nonhomogeneous ionosphere of exponential conductivity profile. The exponential ionosphere model provides slightly lower resonant frequencies and less damping of the ...
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Advanced Optical Materials
Abstract Extremely low‐frequency (below 10 Hz) current‐induced magnetic field detection has significant applications in high‐voltage DC systems, lithium‐ion battery diagnostics, and industrial process monitoring. Nitrogen‐vacancy (NV) ensembles magnetometry typically employs flux concentrators to enhance magnetic detection sensitivity,
Chunlong Li +9 more
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Abstract Extremely low‐frequency (below 10 Hz) current‐induced magnetic field detection has significant applications in high‐voltage DC systems, lithium‐ion battery diagnostics, and industrial process monitoring. Nitrogen‐vacancy (NV) ensembles magnetometry typically employs flux concentrators to enhance magnetic detection sensitivity,
Chunlong Li +9 more
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