DocumentCode :
2343345
Title :
Experimental studies of low-voltage, grating TWT amplifiers
Author :
Joe, J. ; Basten, M.A. ; Scharer, J.E. ; Booske, J.H. ; Wagner, K.
Author_Institution :
Dept. of Electr. & Comput. Eng., Wisconsin Univ., Madison, WI, USA
fYear :
1995
fDate :
5-8 June 1995
Firstpage :
228
Abstract :
Summary form only given, as follows. Recent results are presented from experimental studies of spontaneous emission and linear gain in a low-voltage, sheet-beam-compatible, grating TWT amplifier. A round probe beam from a 10 kV, 0.25 A Pierce gun electron source is utilized for 14 GHz amplifier experiments. From the spontaneous emission measurements we obtain the following valuable informations:(a) measurements of the grating-induced spontaneous emission spectrum which can be correlated with the theoretically predicted linear gain curves, (b) measurements of broad-band noise emission which are critical for amplifier sensitivity characterization, and (c) measurements of spontaneous emission in the backward-wave regime to correlate with start oscillation predictions. The noise emission spectra have been correlated with the most dominant experimental factors including guide magnetic field intensity and body currents. Measurements of linear gain are also compared with the theoretical prediction in both forward and backward-wave regimes. The slow-wave structure consists of a uniform grating that adiabatically tapers to a smooth wall at both ends for impedance matching between the conventional TE/sub 10/ rectangular guide mode and the TE/sub x10/ hybrid slow-wave mode of the grating circuit. Small loop antennas are inserted at each end in smooth-walled rectangular guide sections for input and output signal coupling with the TE/sub 10/ mode. Broadband, high-vacuum-compatible, SiC waveguide attenuator fins provide excellent suppression of unwanted end reflections and prevent the system from self-oscillation in the forward-wave regime.
Keywords :
gain measurement; impedance matching; microwave power amplifiers; slow wave structures; spontaneous emission; travelling wave amplifiers; 0.25 A; 10 kV; 14 GHz; amplifier experiments; backward-wave regime; broad-band noise emission; grating-induced spontaneous emission spectrum; hybrid slow-wave mode; impedance matching; linear gain; linear gain curves; low-voltage grating TWT amplifiers; noise emission spectra; sheet-beam-compatible; signal coupling; slow-wave structure; smooth-walled rectangular guide sections; spontaneous emission; start oscillation predictions; waveguide attenuator fins; Circuits; Electron sources; Gain measurement; Gratings; Impedance matching; Magnetic field measurement; Magnetic noise; Noise measurement; Spontaneous emission; Tellurium;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on
Conference_Location :
Madison, WI, USA
ISSN :
0730-9244
Print_ISBN :
0-7803-2669-5
Type :
conf
DOI :
10.1109/PLASMA.1995.532815
Filename :
532815
Link To Document :
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