A Hybrid Time-Frequency Domain Equalizer for Single Carrier Broadband MIMO Systems

Single carrier frequency domain equalization (SC-FDE) has recently been receiving much attention as an attractive technology for broadband wireless communications for its advantages such as low peak-to-average ratio and reduced sensitivity to carrier frequency offsets, when compared to orthogonal frequency-division multiplexing (OFDM) systems. In this paper, we investigate its combination with multi-input multi-output (MIMO) technology and propose a novel hybrid time-frequency domain equalizer, FDE-NP, which consists of a feedforward frequency domain equalizer and an array of time domain noise predictors (NPs). It is shown that the proposed scheme has lower complexity and achieves better performance and complexity trade-off than the conventional FDE designs. To evaluate the system performance, we will propose an accurate theoretical analysis based on the modified Chernoff bound and show that it is not only applicable to the proposed FDE-NP scheme, but also to general MIMO systems with equalization. By using the developed modified Chernoff bound and along with the simulation results, we will show that the proposed FDE-NP scheme can achieve significant performance improvement over the conventional FDE MIMO schemes.