We present the results of a numerical investigation of the interaction between the ITER ICRF antenna plug (external matching option) and the surrounding wall blanket modules with the commercial software CST Microwave Studio (MWS). In particular we study the RF currents circulating on and between these modules with a simplified rectangular model of the antenna and the blanket. Large currents can circulate on the plug and concentrate on the elements connecting the tiles to the first wall. We consider different grounding configurations (short-circuits and capacitors) aiming at decreasing the amplitude of the currents on the modules connectors. We observe a significant reduction of the RF currents on the connectors as well as a suppression of the propagative modes on the plug.
