High-Power Density Ion Cyclotron Antennas for Next Step Applications

It is generally recognized that the ion cyclotron (IC) heating and current drive technology is applicable to the next step devices, but it is still debated whether current IC launching structures are adequate for high-power density operation in discharges where the edge density profile is modified by the presence of edge-localized mode (ELM) activity. Important issues are the antenna tolerance to load variations (such as those due to ELMs) and minimum parasitic power losses. The proposed ITER IC antenna design addresses these issues through an advanced antenna design. The design principles and the projected performances of the ITER IC antenna are discussed.