Ion Bernstein wave excitation is investigated with the self-consistent two-dimensional particle-in-cell method. The real ion to electron mass ratio is used in simulations in high harmonic frequency bands. The simulation results are compared with linear theory and ray tracing. Successful excitation of the ion Bernstein wave has been demonstrated with the particle-in-cell method. In some cases, the excited wave temporarily propagates in the opposite direction and slows down permanently due to complicated dispersive behavior, which makes it very difficult to use the particle-in-cell method. The excitation is studied as a function of temperature and frequency, i.e., it is determined how the dispersive behavior varies in the parameter space. The simulations indicate that there is a temperature-and-frequency-dependent critical level of coupled energy flux above which excitation fails. Possible effects causing the failure of excitation at high power intensity are identified.