Joint transmit and receive filters design for multiple-input multiple-output (MIMO) systems

Multiple transmit (Tx) and multiple receive (Rx) antennas systems, referred to as multiple-input multiple-output (MIMO) systems, have been proposed to achieve higher data rates in wireless communication systems. In this paper, we investigate joint design of transmitter and receiver for the MIMO system when the channel information is available at both transmitter and receiver. We discuss the problem concerning the design,of Tx and Rx filters with the aim of minimizing the bit-error probability (BEP). We derive the optimum Tx and Rx filters when the number of data symbols is two. For a general number of data symbols, we derive a Tx and Rx filters design criterion referred to as equal signal-to-noise plus interference ratio (SNIR) criterion, and propose Tx and Rx filters based on this equal SNIR criterion. The performance of the proposed filter is compared with that of the conventional minimum mean-squared error (MMSE) filter. Performance analysis shows that the proposed filter provides a significant improvement over the MMSE filter in BEP and spectral efficiency.