DocumentCode :
1411797
Title :
Experimental studies of long-lifetime cold cathodes for high-power microwave oscillators
Author :
Gunin, Aleksandr V. ; Landl, Vladimir F. ; Korovin, Sergei D. ; Mesyats, Gennady A. ; Pegel, Igor V. ; Rostov, Vladislav V.
Author_Institution :
Inst. of High-Current Electron., Acad. of Sci., Tomsk, Russia
Volume :
28
Issue :
3
fYear :
2000
fDate :
6/1/2000 12:00:00 AM
Firstpage :
537
Lastpage :
541
Abstract :
Operation of explosive-emission cold cathodes made from various materials was studied at a large number of pulses at current densities of ~1.04 A/cm2. The cathode voltage and the beam current were ~500 kV and 5 kA, respectively, with a pulsewidth of ~20 ns. At a small number of pulses (⩽103), cathodes of like geometry (even made from different materials) demonstrated similar emission properties. For most of the materials tested, with a large number of pulses (⩾103), the current risetime increased to the fullwidth of the voltage pulse and the maximum current of the vacuum diode decreased. When using a graphite cathode, the maximum current remained invariant until 108 pulses. Mass losses were measured for a series of cathode materials. The results obtained offered the possibility to realize long-lived operation of an X-band relativistic backward-wave oscillator with an almost invariant output power of 350-400 MW during 108 pulses at a pulse repetition rate of 100-150 p.p.s
Keywords :
backward wave oscillators; cathodes; microwave oscillators; relativistic electron beam tubes; 350 to 400 MW; 5 kA; 500 kV; X-band relativistic backward-wave oscillator; beam current; cathode materials; cathode voltage; current risetime; emission properties; explosive-emission cold cathodes; graphite cathode; high-power microwave oscillators; long-lifetime cold cathodes; long-lived operation; mass losses; pulsewidth; vacuum diode; Cathodes; Current density; Diodes; Geometry; Loss measurement; Materials testing; Oscillators; Power generation; Space vector pulse width modulation; Voltage;
fLanguage :
English
Journal_Title :
Plasma Science, IEEE Transactions on
Publisher :
ieee
ISSN :
0093-3813
Type :
jour
DOI :
10.1109/27.887668
Filename :
887668
Link To Document :
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