Design of quasi optical grills for the launch of microwaves into tokamak plasmas

Summary form only given. While lower hybrid (LH) waves are very efficient in controlling the current profiles in the outer edges of a plasma, it is very difficult to design standard multijunction grills to launch waves in the 5-8 GHz range because of cooling and structural stability. However, if one turns to the quasi-optical grill (QOG), one can design microwave launchers that are relatively simple and robust. Applications are made to design of QOG for ITER-like plasmas as well as EBW for NSTX plasmas.