Novel transit-time oscillator (TTO) combining advantages of radial-line and axial TTO
Xu Wei-Li, He Jun-Tao †, Ling Jun-Pu, Song Li-Li, Deng Bing-Fang, Dai Ouzhixiong, Ge Xing-Jun
       

(a) Axial phase space plot and (b) radial phase space plot of HPM source after saturation.