Equivalent spatial-temporal multiuser detection for MC-CDMA systems with uniform linear arrays over frequency-selective fading channels

Joint spatial-temporal multiuser detection (MUD) schemes for DS-CDMA systems with antenna arrays have drawn much attention, which has continued unabated. We derive the equivalent spatial-temporal MUD scheme for MC-CDMA systems with antenna arrays. A uniform linear array (ULA) is applied to the base station of the MC-CDMA system. We first describe the equivalent time-domain DS-CDMA interpretation for the MC-CDMA system. Based on this interpretation, by utilizing the finite alphabet property of the transmitted symbols, an equivalent spatial-temporal multiuser detector is derived for the MC-CDMA system with the ULA over frequency-selective fading channels. Computer simulations illustrate that our algorithm is more robust against noise and can well mitigate multiple access interference (MAI) in multiuser scenarios. In particular, our novel scheme has the potential of providing the anticipated MUD performance gains with a complexity that would be manageable for MC-CDMA systems.