Polarization adjustment of incident transverse electromagnetic waves for optimal mode-conversion to electron Bernstein waves is proposed and analysed. The optimized wave injection excites most efficiently the electrostatic waves at the upper hybrid resonance (UHR) layer. Polarization adjustment is effective for the intermediate range of density gradient near the UHR layer, which has not been covered by the previously proposed schemes of perpendicular injection of X mode for the extremely steep density gradient case and oblique injection of O mode at the optimal injection angle for the gentle gradient case. Various methods of experimental polarization adjustment without detailed information on the density profile are proposed and discussed.
First measurements of line-integrated electron density in an ITER-like configuration using the JET far infrared polarimeter diagnostic