Multiuser interference suppression for the uplink of interleaved MIMO OFDMA

In the uplink of multiple-input multiple-output (MIMO) orthogonal frequency division multiple access (OFDMA) systems, multiuser interference (MUI) occurs due to carrier frequency offsets (CFOs). In this paper, a novel scheme is presented to suppress MUI for the interleaved MIMO OFDMA system. The first stage is to compensate the multiple CFOs, which is based on a calculation of optimum CFO correction value maximizing the average signal-to-interference ratio (SIR). And the second stage uses minimum mean square error (MMSE) frequency domain equalizer (FDE), considering the residual MUI as additive noise, to further improve the systems' performance. Simulation results show that the proposed scheme exhibits a significant improvement over conventional scheme.