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An electrostatic voltmeter for use at extremely high frequencies
Journal of Scientific Instruments, 1937A description is given of the constructional features of a small electrostatic voltmeter in which self-heating errors, due to dielectric losses, have been reduced to a minimum.
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Extremely high-frequency micro-Doppler measurements of humans
SPIE Proceedings, 2014The development of sensors that are capable of penetrating smoke, dust, fog, clouds, and rain is critical for maintaining situational awareness in degraded visual environments and for providing support to the Warfighter. Atmospheric penetration properties, the ability to form high-resolution imagery with modest apertures, and available source power ...
Abigail S. Hedden +4 more
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Extremely High Frequency (EHF) Receivers
2005Advances in millimeter wave components have revived research and development in EHF receivers. There are presently two general approaches to fabricate EHF receivers: the crystal video receiver and wide-band channelization. In both approaches, the small size of the receiver is very much emphasized. The miniaturization includes not only the receivers but
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A Compact Extremely High Frequency MPM Power Amplifier
IEEE Transactions on Electron Devices, 2018The development of a compact radio frequency (RF) vacuum power amplifier for high-resolution airborne radar is described. The amplifier, a microwave power module (MPM), operates in the upper millimeter-wave frequency band of 231.5–235 GHz providing a peak output power of 32 W.
Carter M. Armstrong +12 more
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Playing the notes of DNA with light: extremely high frequency nanomechanical oscillations
Nanoscale, 2015A double nanohole optical tweezer with two trapping lasers beating is used to excite the 10 GHz to 80 GHz vibrational modes of single-stranded DNA fragments.
Abhay, Kotnala +2 more
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Isolation of Actinomycetes from Soil Using Extremely High Frequency Radiation
Microbiology, 2002A new method employing extremely high frequencies (EHFs) is proposed for the selective isolation of actinomycetes from soil. The pretreatment of soil suspensions with EHF wavelengths of 5.6 and 7.1 mm led to a nonselective isolation of actinomycetes. At the same time, the irradiation of soil suspensions within wavelength bands of 3.8-5.8 and 8-11.5 mm ...
Iu V, Li, L P, Terekhova, M G, Gapochka
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A hearing aid for subjects with extreme high-frequency losses
IEEE Transactions on Acoustics, Speech, and Signal Processing, 1976A speech processing system has been developed in which the unvoiced portion of speech is bandwidth compressed from an original bandwidth of 4000 Hz into a low-frequency band not exceeding 1000 Hz, in which hearing impaired subjects with severe high-frequency hearing losses still possess some residual speech perception.
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Spectrum prediction for high-frequency radar based on Extreme Learning Machine
2015 Seventh International Conference on Advanced Computational Intelligence (ICACI), 2015In this paper, a new predictive method based on Extreme Learning Machine is proposed to predict the spectrum data obtained from by frequency monitoring system of high-frequency radar. In order to improve the forecasting accuracy and real-time of spectrum prediction of high-frequency radar, Empirical Mode Decomposition method is used for the ...
Zhifen Yang, Ling Yang, Yanping Fu
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Frequency and clinical consequences of extremely high maternal serum PAPP‐A levels
Prenatal Diagnosis, 2003AbstractA multicentre study was carried out to determine the frequency and clinical consequences of extremely high maternal serum pregnancy‐associated plasma protein (PAPP)‐A. There was a total of 79 pregnancies with PAPP‐A exceeding 5.0 multiples of the gestation‐specific median in a series of 46 776 pregnancies tested (0.2%) at the 7 collaborating ...
H, Cuckle +11 more
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Surface roughness modeling for extremely high frequency applications
In this work, we show electromagnetic simulations of surface roughness for multiple conventional antennas applicable for 6G networks potentially operating in the W-band (75–110 GHz). We show simulations of the surface roughness of four devices, such as a horn antenna, a patch antenna, a rectangular waveguide, and a microstrip transmission line. Finally,Sedov, Artem +5 more
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