Transmission strategies for correlated MIMO links with imperfect channel estimates

We investigate the transmit precoder design problem for a multiple input multiple output (MIMO) link with correlated receive antennas, considering the effect of channel estimation. We propose transceiver structures that are optimum in the sense of minimizing the total MSE and distributing the total MSE equally among the parallel data streams. We also investigate the problem of how the correlated MIMO link should distribute its total available power between power expended for channel estimation versus data transmission. The optimum power allocation problem between the training sequences for channel estimation and data transmission for the correlated MIMO link is shown to have a unique solution, that is different than the uncorrelated case. The performance of the system is observed to be more sensitive to transceiver design rather than the power allocation. The results demonstrate that the correlation structure of the MIMO link has a profound effect on the performance, and that the transceiver optimization should be done by taking both the correlation and the channel estimation process into account.