Simulation on effect of poloidal power spectrum on lower hybrid wave propagation

The coupling of lower hybrid wave to the plasma is acrucial issue for efficient current drive in tokamaks. This paperestablishes a new coupling model which assumes the antenna to be acurved face and the plasma to be a cylinder. Power spectrum consideringthe coupling between wave-guides in both poloidal and toroidaldirection is simply estimated and discussed. The effect of the poloidal wavevector on wave propagation, power deposition and driven current isalso investigated with the help of lower hybrid current drive code.Results show that the poloidal wave vector affects the ray tracing,and also has effect on power deposition and driven current. Theeffect of the poloidal wave vector on power deposition and drivencurrent profile depends on plasma parameters. Preliminary studiessuggest that it seems possible to control the current profile byadjusting the poloidal phase difference between the waveguide inpoloidal direction.