Achieving Near-Optimal Detection Using Adaptive Joint Combination of MLD and MMSE-SIC over Spatially Correlated MIMO Channels

We develop an efficient hard-detector for multiple-input multiple-output (MIMO) channels, which adaptively combines maximum-likelihood detection (MLD) and minimum-mean-square-error (MMSE) with a successive interference canceler (SIC) together. Unlike the conventional joint combination scheme which may suffer from considerable degradation in bit-error-rate (BER) performance over correlated channels and where only one data stream is detected by MLD, our proposed scheme adaptively controls the number of data streams to be detected by MLD based on the analytical characterization of reliability for the detection. Simulation results illustrate that near-optimal BER performance can be obtained at much lower computational complexity by the proposed method as compared to existing techniques, regardless of the spatial correlation of the MIMO channels.