新型反馈式轴向同轴虚阴极振荡器

提出一种利用低磁场导引环形电子束在同轴波导内轴向激励虚阴极振荡的新型虚阴极振荡器.利用反馈式结构，使虚阴极在由反馈环、阳极箔和同轴波导构成的高品质因子准谐振腔内形成.作用腔内环形电子束激励同轴波导TM₀₁模式，在相对低品质因子的同轴提取区转化为TEM主模输出.用25维KARAT粒子模拟软件研究得到束波功率转换效率12%，输出微波平均27 GW，中心频率38 GHz.关键词：环形电子束轴向导引磁场同轴波导反馈环

A novel configuration of vircator with coaxial waveguide

The space-charge-limited currents of both solid electron beam and annular electron beam in cylindrical waveguide are derived from the nonlinear Poisson equation for potential in the region of electron beams. Corrections for the transverse motion of electrons are made to the solution, which bring more consistent with the results from PIC simulations. Though numerical computation, it is showed that electrons located along the axis and by outer radius of solid and annular electron beams respectively and electrons standing near to the outside of the beam has larger axial velocity than these inside. This approach is available for analyzing the characteristics of electron beam transporting in high power microwave generator with other configuration waveguide.