Two-dimensional finite-element method analysis of various antennas for ICRF plasma heating

Two-dimensional finite-element analysis is performed for ion-cyclotron range of frequency (ICRF) antennas with various cross-sectional configurations. Interest is mainly focused on the quantitative difference in the input impedance among various antennas such as the normal loop antenna, the antenna with surrounding limiter walls, and the antenna buried into the cutoff cavity. For analytical simplicity, the cold plasma approximation is used. The numerical results show how the input impedance is affected by the presence of the limiter walls or the cutoff cavity. The code described can be applied to the designs of ICRF antennas with a wide range of plasma parameters and antenna geometries