A multicarrier DS-CDMA system using both time-domain and frequency-domain spreading

This paper proposes multicarrier direct-sequence code-division multiple-access (MC DS-CDMA) scheme, which employs both time (T)-domain and frequency (F)-domain spreading. The achievable detection performance in the context of synchronous TF-domain spread MC DS-CDMA, when communicating over an additive white Gaussian noise (AWGN) channel is investigated. The performance of three different detection schemes is investigated, which include the single-user correlation based detector, the joint TF-domain decorrelating multiuser detector (MUD) and the separate TF-domain decorrelating/MMSE MUD. Our simulation results show that the separate TF-domain decorrelating/MMSE MUD scheme is capable of achieving a better bit error rate (BER) performance than that of the significantly more complex joint TF-domain MUD schemes.