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Recent research has shown that frequency domain pre-equalization (FDPE) can provide broadcast transmissions over multi-input multi-output (MIMO) frequency selective channels, where the multiple receivers need limited processing. In this paper, we consider the combination of FDPE with parallel and successive Tomlinson-Harashima Precoding (THP) and propose two novel FDPE MIMO schemes, which are referred to as FDPE-P-THP and FDPE-S-THP, respectively, based on the minimum mean square error (MMSE) criterion. The ordering algorithm in the FDPE-S-THP scheme is considered and it is shown that the system with even a randomly selected order can perform almost as well as that with the optimal one. This paper further develops an accurate theoretical performance analysis methodology for the proposed FDPE-THP schemes. Numerical results along with analytical results demonstrate the significant performance improvement of our proposed schemes compared to the conventional FDPE MIMO schemes. The channel estimation errors and channel variation effects on the proposed system are also investigated. It is shown that the performance degradation due to channel variation can be efficiently reduced by applying channel prediction. [ABSTRACT FROM AUTHOR]

This paper is concerned with the low-cost iterative equalization/detection principles for coded linear systems with cyclic prefixes. Turbo frequency-domain-equalization (FDE) is applied to systems that may contain the joint effect of multiple-access interference (MAI), cross-antenna interference (CAI) and inter-symbol interference (ISI). We develop an SNR-variance evolution technique for the performance evaluation of the proposed systems. Numerical results in various channel environments demonstrate excellent agreement between the predicted and simulated system performance. [ABSTRACT FROM AUTHOR]

This paper describes a silicon receiver for a multiple-input multiple-output (MIMO) wireless channel that supports up to 28.8 Mb/s using a 4 × 4 QPSK configuration over a 5-MHz frequency selective channel. The architecture has two key components: a space-time equalizer that mitigates both spatial and temporal effects of the channel, and a maximum likelihood detector with approximate a posterior probability (ML-APP) soft estimates of the transmit vectors over the MIMO configuration. The space-time equalizer uses an adaptive tap training process that includes a pilot correlator to reduce adaptation noise. The device is 685 k effective logic gates (11.6 mm²) in 0.18-pm 6LM CMOS. [ABSTRACT FROM AUTHOR]