Title :
A wide-bandwidth coupler for a free-electron-maser amplifier
Author :
Foster, Patricia R. ; Gamble, David
Author_Institution :
Microwave & Antenna Syst., Malvern, UK
Abstract :
The coupler described in this paper is designed to separate the hot electron beam and the high-power microwave signal in a free-electron-maser amplifier. This coupler has been designed, built, and tested and is intended for operation across the 8-18 GHz frequency band. It consists of an arc of quadridged waveguide with the electron beam entering between ridges. The RF performance was found to be critically dependent on the radius and length of the arc. The measured return loss is better than -30 dB across the band with an insertion loss of less than 0.1 dB.
Keywords :
electromagnetic coupling; electron optics; free electron lasers; losses; masers; microwave devices; ridge waveguides; waveguide couplers; -30 dB; 0.1 dB; 8 to 18 GHz; RF performance; arc length; arc radius; coupler design; coupler test; electron beam; free-electron-maser amplifier; high-power microwave signal; hot electron beam; insertion loss; operation frequency band; quadridged waveguide arc; return loss; wide-bandwidth coupler; Broadband amplifiers; Electron beams; High power amplifiers; Loss measurement; Microwave amplifiers; Optical coupling; Radio frequency; Radiofrequency amplifiers; Signal design; Testing;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2002.807828
