Joint transceiver design for uplink MIMO MC-CDMA systems

Multiuser interference (MUI) and multiple-antenna interference (MAI) are two challenging issues in design of multicarrier code-division multiple-access (MC-CDMA) systems for communication through multiple-input multiple-output (MIMO) channels. In this paper, by utilizing channel information in both transmit and receive sides, we propose two linear joint transmitter-receiver design methods for multiuser uplink communication in the MIMO MC-CDMA system based on deploying the singular value decomposition (SVD) technique and space - frequency spreading code. The first method called total interference cancellation (TIC) is able to completely eliminate the MUI and the MAI by employing pre-equalizer and beamformer at the chip level in the transmitter. However, due to small singular values of the subchannel matrices, the TIC performance is degraded. Another SVD-based method called symbol-chip level minimum mean square error (SC-MMSE) is developed to overcome the effect of small singular values. In this method, a combined equalizer and transmit/receive beamformers is designed at chip level based on using the MMSE criterion at symbol level. For different scenarios, simulation results show that the proposed methods are able to mitigate the MUI and the MAI in comparison with the uplink single user scenario.