MMSE-based Detector for Spatial Modulation OFDM Systems with Multiple CFOs

In this paper, a low-complexity vector-by-vector (VV) based minimum mean square error (MMSE) detector is proposed in the presence of carrier frequency offset (CFO) in spatial modulation orthogonal frequency division multiplexing (SM-OFDM) systems. Its main benefit lies in that the CFO matrix in the proposed detector is considered as a component of the channel transfer matrix. Furthermore, the SM symbol is treated as an entire vector when performing soft interference cancellation (SIC) in the proposed MMSE detector. Finally, the structure of the CFO matrix is exploited in order to strike a flexible trade-off between complexity and performance. Simulation results demonstrate that the proposed detector can provide considerable performance improvement compared to conventional detectors at a moderate complexity cost in both uncoded and coded SM systems.