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Vacuum electronic (VE) power amplifiers are being developed between 100 GHz and 1 THz. Minimum power goals are 50 watts at 220 GHz, and 100 mW at 670 GHz. These devices will use advanced, high current density cathodes, a folded waveguide as the slow-wave circuit, and a depressed collector for overall device efficiency. Operation at duty cycles of 50-100% is anticipated.
We propose to use an addressable array of emitters to provide a distributed electron source for use in a crossed-field amplifier (CFA). In our approach the dynamic control of the microwave device is obtained by using feedback from an array of device inputs and outputs to control the electron current density versus position within the device. The feedback consists of measurements of the RF output (noise,...
The authors proposed a photonic-crystal diode resonator capable of applying both DC-bias field and RF field at the same time, that enables the electron flow continuously to the anode regardless of the RF phase and amplitude as long as the modulation depth, the ratio of maximum RF voltage amplitude to DC-bias, is less than one. The proposed scheme employs a novel diode resonator consisting of two metal...
Summary form only given. We present the development of a plasma-enhanced chemical vapor deposition (PECVD) system for deposition of multi-walled, vertically aligned Carbon Nano-Tubes (CNT) as cathode field emitter sites in a large (1000 x 1000), 1 cm2 area array. The CNT deposition is compatible with the use of Si wafers containing the individual emitter site ballasts in the form of Si n-type JFETs...
Recent demonstration of low-voltage high-transconductance field emitter array operation holds promise for the successful development of reliable cold cathode vacuum electronics device technologies. This paper reports on the experimental studies of implementation of such field emitter arrays as the electron source for a moderate power traveling wave tube (TWT) operating in the C-band frequency regime...
Summary form only given. L-3 Communications continues development and testing of a moderate power helix TWT incorporating a new low-voltage high-transconductance field emitter array cold cathode developed by SRI International. The TWT employs a custom electron gun required to control the high beam space charge density created in the acceleration region between the HV cathode surface and the grounded...
L-3 Communications continues development and testing of a moderate power helix TWT incorporating a new low-voltage high-transconductance field emitter array cold cathode developed by SRI International. The TWT employs a custom electron gun required to control the high beam space charge density created in the acceleration region between the HV cathode surface and the grounded input TWT helix. A custom...
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