Results 261 to 270 of about 93,397 (307)

Free electron maser amplifier experiments

2011 Abstracts IEEE International Conference on Plasma Science, 2011
Centimetre wavelength broadband amplifiers at MW power levels are required for a number of applications including RaDAR as well as spherical tokamak fusion plasma heating and diagnostics. Recent publications1,2,3 on gyro-amplifiers have shown exceptional gain, power, bandwidth and efficiency performance in this wavelength range, however, when larger ...
C. G. Whyte, C. W. Robertson, K. Ronald, A. R. Young, W. He, A. W. Cross, P. MacInnes, A. D. R. Phelps   +7 more
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Transferred electron amplifiers and oscillators

IRE Transactions on Electron Devices, 1961
In some semiconductors the conduction band system has two minima separated by only a small energy, and the lower minimum has associated with it a smaller electron effective mass than the upper minimum. At high electric fields it should be possible to transfer electrons to the upper minimum where they will have a lower mobility.
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Chemically Amplified Electron-Beam Photoresists

Chemistry of Materials, 1996
Two novel series of electron-beam photoresists possessing high sensitivity and contrast have been developed based on chemical amplification chemistry. The amplification process relies on the electron-beam-induced generation of acids derived from the decomposition of onium salts to catalytically deblock pendant tert-butyl ester groups along the backbone
James V. Crivello, Sang-Yeon Shim
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Electronically tuned UHF power amplifier

2011 IEEE MTT-S International Microwave Symposium, 2011
Summary form only given, as follows. This electronically tunable UHF power amplifier (PA) is based upon a Gallium-Nitride (GaN) HEMT operated in class C. The gate input is tuned by two arrays of varactor diodes. The drain output is tuned by a three-stub tuner whose stub lengths are controlled by pin diodes. From 325 to 800 MHz (factor of 2.5∶1), the PA
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Nondegenerate electron beam parametric amplifiers

IEEE Transactions on Electron Devices, 1963
Cyclotron wave amplifiers with a pump-to-signal frequency ratio of 5:1 (rather than the usual 2:1) have been built and have given a single-channel noise figure of 2 db. This paper reports on the difficulties which had to be overcome and the restrictions which had to be observed before achieving what, at the start, had looked deceptively simple.
R. Adler, G.W. Hrbek
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Circuitless electron beam amplifier (CEBA)

1980 International Electron Devices Meeting, 1980
A theoretical analysis is presented for a novel high power microwave/millimeter wave amplifier (herein called CEBA) that requires no radio frequency (RF) circuit structure. The electron beam is treated as an active dielectric serving the dual purpose of slow-wave circuit and amplification source.
C. De Santis, L.J. Jasper
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Comparison of Hot Electron and Related Amplifiers

1962 International Electron Devices Meeting, 1962
It is proposed that novel amplifiers be compared with each other and with existing amplifiers on the basis of as many figures of merit as are calculable. The bipolar transistor; field-effect transistor; Schottky-emitter, space-charge-limited-emitter, and tunnel-emitter, metal-base, hot-electron amplifiers are compared with respect to frequency cutoff ...
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A nondegenerate electron beam parametric amplifier

IRE Transactions on Electron Devices, 1961
In a non-degenerate electron beam parametric amplifier (EBPA), signal and idler frequencies are far apart. This contrasts with the more familiar degenerate type which uses a pump frequency approximately equal to twice the signal frequency, thus placing the idler near the signal.
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Free electron maser amplifier experiments

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2000
Abstract We present results from the X-band reversed guide magnetic field Raman Free Electron Maser (FEM) amplifier experiment at Strathclyde University. The FEM has been designed for zero slippage to achieve maximum instantaneous bandwidth. The tuneablity is further extended by the adjustment of beam voltage and undulator field strength.
Whyte, C.G., Jaroszynski, D.A., Cross, A.W., He, W., Ronald, K., Young, A., Phelps, A.D.R.   +6 more
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Amplifiers before electronics — the Magnifiers

2008 IEEE History of Telecommunications Conference, 2008
Amazing ingenuity was shown by dasiaelectricianspsila prior to the development of the thermionic valve (tube) into a reliable means of amplification of extremely low current signals in the earliest telecommunication systems. This paper classifies the devices used and then describes the principles involved in the group known as magnifiers.
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