Performance of turbo coded multicarrier CDMA with iterative multiuser detection and decoding

The performance of a turbo coded MC-CDMA uplink with iterative multiuser detection is evaluated. Optimal likelihood ratios are computed based on the maximum a posteriori criterion using the multiuser signal structure and a priori information of code bits of all other users available from channel decoders. Combining turbo coding and multiuser detection in MC-CDMA has shown performance close to the single user bound with a few iterations of joint detection and decoding. Additionally, a suboptimal approach using soft interference cancellation is also implemented for the uplink transmission and compared with the conventional methods. Simulation results are presented in a Rayleigh multipath fading environment for a typical data transmission scheme.