介质加载矩形波导栅行波管的小信号增益计算

The gain computation for the traveling wave tube with dielectric-loaded rectangular waveguide grating

介质加载矩形波导栅行波管是一类新型毫米波大功率器件.给出了此结构引入电子束后的"热"色散方程,并利用"牛顿下山"法求解了此复杂系数超越方程,研究了介质加载以及电子束参数对小信号增益的影响.计算结果表明:介质加载可以扩大矩形波导栅行波管的带宽,而增益有所减小.为了弥补增益的降低,可以适当增加槽深度,也可在一定的范围内提高电子束电流.给出的结论对于研制此类行波管具有一定的指导意义.

The dielectric-loaded rectangular waveguide grating traveling wave tube （TWT） is a new kind of high power millimeter wave device. The ＂hot＂ dispersion equation of this circuit loaded with an electron beam is presented in this paper, and the ＂Newton downhill＂ method is used to solve the transcendental equation. The investigations of the effect of dielectric-layer dimensions and electron beam parameters on the small signal gain are carried out. The calculation results indicated that dielectric-loading can widen the bandwidth of the rectangular waveguide grating TWT and decrease the gain. In order to make up the gain-decrement, the groove-depth can be slightly increased, or the current of the electron beam enhanced within certain limits. The presented analysis will be a guide to the design of this kind of TWTs.