Development of transmission lines at frequencies of 28-37 GHz for application with ECR ion sources

The use of available superconducting (SC) magnet technology for ion plasma sources allows the application of electron cyclotron resonance heating (ECRH) at frequencies up to 37 GHz. In that range gyrotrons are the efficient sources. The overmoded transmission lines (needed for the high power) between gyrotron and ion source can be designed with methods also used in ECRH experiments for fusion plasma heating. This paper reports on design of several components such as mode converters, bends, DC breaks and couplers.