Ray-tracing in the electron-cyclotron frequency region

The tracing of the geometrical optics rays in toroidal geometry and in the electron-cyclotron frequency range has been done numerically. The results presented are relevant to the extraordinary-mode propagation and conversion at the upper-hybrid resonance layer. High-density regime refraction effects, together with strong bending of the warm Bernstein rays along the toroidal direction and resonance-cone structure generation, are the main features of the numerical output.