Blind bandwidth-efficient schemes for CDMA on dispersive MIMO channels

In this paper we consider a general asynchronous frequency-selective multiuser CDMA system with transmit and receive antennae, where the information data stream is space-time encoded. Sufficient conditions for fully blind detection are established and several detection strategies are presented. The proposed detection strategy consists of three different stages. The first block exploits the deterministic structure imposed by the spreading code to jointly estimate the symbol timing. The second stage consists of a sequence of observable consisting of the two useful signals and residual interference plus white noise. The last stage is about space-time decoding of the ordered sequence.