Three-dimensional RF and circuit modelling of the revised ITER ICRF launcher design

The ITER Ion Cyclotron Heating and Current Drive antenna design has undergone significant improvements driven by mechanical considerations. We present a series of numerical assessments of the RF properties of the resulting new architecture. Various designs aiming at using the service stub as a mechanical support were analysed and compared to the performance of the 2012 Preliminary Design Review (PDR) version taken as reference resulting in the selection of the ”internal service T-stub” design. CST MWS/Ansys HFSS 3D models of the sub-components of the antenna were developed and simulated, and the resulting scattering matrices were integrated into transmission line (TL) models to evaluate RF coupling properties and RF power losses on the conductors. The results are compared with the 2012 performances and the differences are discussed. Also, 3D RF fields maps are produced and areas of improvement are identified.