Title :
A 3 KW pulsed, 10% duty cycle, high gain X-band helix TWT
Author :
Carignan, R.G. ; Pittack, U.J.
Author_Institution :
Microwave & Power Tube Div., Raytheon Co., Waltham, MA, USA
Abstract :
This paper describes the design and performance of a 3 00 W average, X-band travelling wave tube. The beam is formed with a shadow gridded gun and focused with periodic permanent magnets. Although designed for a narrow-band radar application, peak power of over 3 KW is obtained over the band 7 to 11 GHz. A peak power level of over 4 KW is obtained with optimum adjustment. Gain at saturated output power varies from over 60 db at 7 GHz to 48 db at 11 GHz. Basic efficiency over 20% and depressed collector efficiency of 3 0% is achieved. Excellent stability against oscillation is achieved at all power levels. This is obtained by the use of a fastwave backward wave oscillation suppression technique. The rf design, including oscillation suppression, was carried out with the aid of a large signal computer simulation program. Thermal design includes a special helix support technique which provides high thermal conductivity with minimum dielectric loading of the slow wave structure. Prototype tubes were operated in air cooled ebullient packages, however the high efficiency of this tube would allow cooling by conduction to a base plate.
Keywords :
backward wave oscillators; cooling; permanent magnets; radar applications; travelling wave tubes; X-band travelling wave tube; air cooled ebullient packages; bandwidth 7 GHz to 11 GHz; cooling; fastwave backward wave oscillation suppression; high gain X-band helix TWT; high thermal conductivity; minimum dielectric loading; narrow-band radar application; periodic permanent magnets; power 3 kW; rf design; shadow gridded gun; slow wave structure; special helix support; thermal design; Abstracts; Electron beams; Microwave circuits; Microwave oscillators; Perpendicular magnetic anisotropy;
Conference_Titel :
Electron Devices Meeting (IEDM), 1974 International
Conference_Location :
Washington, DC
DOI :
10.1109/IEDM.1974.6219797