Cyclic-Prefix CDMA System with Chip Based Equalization and Interference Cancellation

In this paper, a chip-level MMSE frequency domain equalizer (FDE) is investigated for a cyclic-prefix CDMA (CP-CDMA) system. The multiple access interference (MAI) and inter chip interference (ICI) is reduced at the chip level before despreading. One code multiplexed pilot channel carries a higher power than dedicated channels and is utilized for channel estimation. It also brings high MAI to the other users. In this paper, the impact of imperfect channel estimation is studied and a pilot interference cancellation algorithm is proposed. We deploy a high power pilot channel to obtain good channel estimates, subsequently, the high MAI along with the pilot channel is removed by the proposed algorithm. Performance of the proposed algorithm is shown by computer simulations