International Journal of Computer Science and Telecommunications
In this paper, the authors carry out a performance evaluation of Multiple-Input Multiple-Output (MIMO) and Hybrid Automatic repeat ReQuest (HARQ) techniques for Single-Carrier Frequency Division Multiple Access (SCFDMA) of the LTE uplink system. Different MIMO schemes such as single-antenna port (SISO or SIMO), Transmit Diversity (TD) and Spatial Multiplexing (SM) are described and simulated. In this paper, they propose an advanced soft combining method of HARQ transmissions which is called Linear MiniMum Square Error Soft Combining (LMMSE-SC). In this paper, the LMMSE equalizer operates jointly the spatial diversity provided by MIMO technique and the temporal diversity provided by the HARQ retransmissions.