-To achieve high spectral and power efficiencies, future broadband wireless systems should combine spatial multiplexing techniques employing multiple transmit and receive antennas with transmission schemes suitable to severely time-dispersive channels such as block transmission techniques, with appropriate CP (Cyclic Prefix) and employing FDE (Frequency-Domain Equalization). Moreover, the signal to be transmitted by the MT (Mobile Terminal) should have a reduced peak power, as well as low envelope fluctuations, so as to allow an efficient power amplification.In this paper we consider the uplink transmission within a DS-CDMA system employing CP-assisted block transmission techniques combined with spatial multiplexing techniques that require multiple antennas at both the transmitter and the receiver. We present an efficient frequency-domain receiver structure with an iterative MUD (MultiUser Detection).It is shown that the performance of the proposed receiver can be close to the single-user MFB (Matched Filter Bound), even for fully loaded systems, in severely time-dispersive channels and/or in the presence of strong interfering signals.