Performance and complexity analysis of sub-optimum MIMO detectors under correlated channel

The interest in multiple antennas systems comes from its high spectral and/or energy efficiency under scattered environments, being an ongoing research topic in wireless communication systems. In this work, different MIMO equalizers, detection techniques (ordering, interference cancellation, lattice reduction, list reduction) and its combination have been analyzed in order to find the best complexity-performance trade-off topology. Also, it has been considered the correlation between antennas, which is invariably occurs in realistic scenarios and deteriorates the performance of MIMO systems. From this perspective, the goal of this paper is to point out a MIMO architecture with reasonable complexity, while holding suitable performance and full diversity under correlated channel scenarios. We have found that combining lattice reduction (LR) technique and Chase List (CL) detection enables slight BER improvements, but at a relatively high cost complexity. Furthermore, ordering has been shown to be ineffective at high correlated and SNR scenarios with large number of antennas, where no ordering is preferable.