AbstractThe design and development of an EC beam launcher are described for the ITER EC H&CD system for plasma heating and on/off axis current drive. The launcher in an equatorial port (an equatorial EC launcher) has three movable mirrors and can inject the EC wave beam power of 20 MW with continuous toroidal steering of 20–45° (r=0–0.6a). The rf frequency is 170 GHz. The front shield of the equatorial EC launcher is designed, and has three narrow slots for rf injection. A 10 atm resistant torus diamond window for a vacuum and a tritium boundary is developed and introduced to the launcher design. Nuclear analysis by the two-dimensional radiation transport code, DOT3.5 for the equatorial EC launcher was carried out and showed that the present neutron radiation shield structure of the launcher could satisfy the required shielding criteria.