Full wave simulation of the iter relevant coaxial cavity gyrotron operation

New generation of gyrotrons based on coaxial cavities with a corrugated inner conductor is able to reach the multi-megawatt output power in a continuous wave (CW) regime. The development of an industrial prototype of a coaxial cavity gyrotron with an RF output power of 2 MW in CW regime at 170 GHz is now in progress at the Centre de Recherches en Physique des Plasmas, Lausanne, Switzerland. The pre-prototype tube (with the same main components) has been developed at the Karlsruhe Institute of Technology (KIT) (former Forschungszentrum Karlsruhe (FZK)) to verify the design of the most critical components of the prototype. The coaxial gyrotron cavity is higherly overmoded and is designed to operate on the TE34jι9 mode. Usage of the corrugated inner conductor allows reducing problems of the mode competition and beam voltage depression. However the reliable design consideration of such a cavity becomes more complicated.