  The sustainment of steady-state plasmas in tokamaks requires efficient
current drive systems. Lower Hybrid Current Drive (LHCD) is currently the most
efficient method to generate a continuous additional off-axis toroidal plasma
current as well as reduce the poloidal flux consumption during the plasma
current ramp-up phase. The operation of the Tore Supra ITER-like LH launcher
has demonstrated the capability to couple LH power at ITER-like power densities
with very low reflected power during long pulses. In addition, the installation
of eight 700kW/CW klystrons at the LH transmitter has allowed increasing the
total LH power in long pulse scenarios. However, in order to achieve pure
stationary LH sustained plasmas, some R\&D are needed to increase the
reliability of all the systems and codes, from the RF sources to the plasma
scenario prediction. The CEA/IRFM is addressing some of these issues by leading
a R\&D program towards an ITER LH system and by the validation of an integrated
LH modeling suite of codes. In 2011, the RF design of a mode converter has been
validated at low power. A 500 kW/5 s RF window is currently under manufacturing
and will be tested at high power in 2012 in collaboration with NFRI. All of
this work aims to reduce the operational risks associated with the ITER
steady-state operations.
