Title :
A 94 GHz overmoded coupled cavity TWT experiment
Author :
Kowalski, Elizabeth J. ; Guss, William C. ; Shapiro, Michael A. ; Temkin, Richard J.
Author_Institution :
Plasma Sci. & Fusion Center, Massachusetts Inst. of Technol., Cambridge, MA, USA
Abstract :
A 94 GHz overmoded coupled-cavity Traveling Wave Tube (TWT) has been designed with 30 dB of gain and 300 W peak power output. An experiment is being fabricated to test the overmoded TWT. The device operates in the TM31 mode with minimal losses, and a lossy AlN dielectric loading is selectively placed in the structure to suppress unwanted modes in the cavities. A cold test of the overmoded coupled-cavities was machined in Glidcop and agrees well with simulation. The TWT experiment is currently under operation, with a 2.5 kG solenoid magnet, 2 microsecond pulse modulator, and in-house designed 30 kV Pierce electron gun. An initial beam test of the 30kV, 320 mA Pierce electron gun shows good agreement with Michelle simulations, and further results are forthcoming.
Keywords :
electron guns; millimetre wave tubes; pulse modulation; solenoids; travelling wave tubes; Glidcop; Michelle simulation; Pierce electron gun; TM31 mode; current 320 mA; frequency 94 GHz; gain 30 dB; lossy AlN dielectric loading; microsecond pulse modulator; overmoded-coupled cavity TWT experiment; power 300 W; solenoid magnet; time 2 ms; traveling wave tube; unwanted mode suppression; voltage 30 kV; Cavity resonators; Copper; Dielectric losses; Electron tubes; Load modeling; Loading; TWT; electron gun; microwaves; overmoded coupled-cavity; vacuum electronics;
Conference_Titel :
Vacuum Electronics Conference, IEEE International
Conference_Location :
Monterey, CA
DOI :
10.1109/IVEC.2014.6857548
