Abstract
In this paper, a modified detection approach based on minimum mean-square error (MMSE) sorted QR decomposition (SQRD) for turbo coded multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems is presented. In conventional MMSE SQRD based detection, a component of the symbol to be detected is still present in the interference term, leading to less efficient log likelihood ratios (LLRs) passed to soft decoder. By moving this symbol component into the signal term, the modified MMSE SQRD based detection can provide more efficient LLRs for soft decoder. Simulation results show that the proposed detection can achieve significant performance gain.