MIMO Transmitter Optimization with Mean and Covariance Feedback for Low SNR

Multiple-input multiple-output system capacity can be improved when there is channel state information at the transmitter (CSIT). This paper proposes a transmission optimization strategy that aims to maximize the mutual information using statistical CSIT. A second order approximation method is used to optimize the transmit covariance matrix. The proposed scheme is compared to the first order approximation, equal power allocation, and waterfilling schemes.