First, we proved that the - Columnwise Complementary codes is better than - Columnwise Complementary code in time selective channel by explaining the probability of happening MAI elimination in frequency domain and proposing a method to use - Columnwise Complementary codes in one cell. Furthermore, we proposed the method to increase the capability of resisting of frequency selective fading channel without decreasing the capability of resisting of time selective fading channel. Finally, we showed some simulation results about receiver velocity and MAI elimination in frequency domain.