Title :
Overmoded W-band traveling wave tube (TWT) design and test
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 :
We report the design and experimental test of a W-band overmoded traveling wave tube amplifier. The TWT circuit is designed to operate in the TM31 mode at 94 GHz and utilizes dielectric loading to suppress unwanted lower order modes. 3-D CST PIC simulations at 31 kV, 310 mA predicted 32 dB of gain and 300 W peak output power. Testing of the overmoded TWT found zero-drive stable operation with full suppression of unwanted modes. Operating at 94.26 GHz, 27 dB of circuit gain (21 dB of device gain) and 55 W peak circuit output power (25 W peak device output power) were measured at 31 kV with 250 mA current on the collector. Simulations predicted 28 dB of circuit gain, in good agreement with experiments.
Keywords :
travelling wave amplifiers; 3D CST PIC simulations; TM31 mode; TWT circuit; W-band overmoded traveling wave tube amplifier; current 250 mA; current 310 mA; frequency 94 GHz; frequency 94.26 GHz; gain 21 dB; gain 27 dB; gain 28 dB; gain 32 dB; overmoded W-band traveling wave tube; power 300 W; power 55 W; voltage 31 kV; zero-drive stable operation; Cavity resonators; Current measurement; Dielectrics; Gain; Loading; Power generation; Solid modeling; TWT; vacuum electronics; w-band;
Conference_Titel :
Vacuum Electronics Conference (IVEC), 2015 IEEE International
Conference_Location :
Beijing
Print_ISBN :
978-1-4799-7109-1
DOI :
10.1109/IVEC.2015.7223740
