Electromagnetic sub-bands in an axisymmetric doubly rippled wall metallic slow wave structure

摘要: Slow wave structure (SWS) is the vital component of slow type high-power microwave (HPM) devices where kinetic energy an axially streaming electron beam resonantly extracted to produce radiation. The frequency generated predominantly depends on and dispersion characteristics SWS. Many types SWSs have been investigated implemented in real experiments. Among them, cylindrical metallic structures with sinusoidally rippled inner wall gained popularity backward oscillators. To enhance efficiency devices, prolonged stable interaction EM important. One possible techniques improve performance could be use non-uniform In this study, a doubly SWS considered. radius varied two periods. Using linear theory, relation inside absence has analysed numerically. It observed that single band conventional decomposed into several sub-bands depending ratio length Some are so flat radiation can made insensitive fluctuation.