Error performance of 8-QAM trellis-coded MC-CDMA with controlled equalization over wireless channels

This paper presents a novel combination of 8-QAM trellis codes with multi-carrier code division multiple access (MC-CDMA) and controlled equalization for multiuser downlink Rayleigh fading channel. In literature, minimum mean square error (MMSE) is known to be the optimal single user detection (SUD) technique. We show that the proposed system, with 16-state encoder and full system load, outperforms an equivalent system that uses MMSE as the equalization technique. Moreover, as the number of active users increase from single user load to a fully loaded system, error performance of the proposed system surpasses an equivalent system using MMSE. This suggests that the proposed system is more robust to multiple access interference (MAI) as compared to that with MMSE.