Optimal Transmitter Eigen-Beamforming And Space-Time Block Coding Based On Channel Correlations With Qos Constraints

Optimal transmitter designs are well-documented, and widely applied. Traditionally, the transmitter is constrained on its average transmit power, and the transmit processing is designed to somehow maximize the quality of the communication, such as bit error rate or capacity of system. However, in many situations, the opposite formulation of the problem may be more desired. This paper considers such communications through multiple-input multiple-output (MIMO) channels. With constrained on quality of service (QoS) requirements in terms of symbol error rate (SER), the optimal transmit eigen-beamforming is designed to minimum the. average transmit power based on channel correlations feedback. In order to get the optimal allocated power for each direction, a practical. and efficient water-filling algorithm is proposed. Coupled with orthogonal space-time block codes, this optimal loading algorithm can meet the QoS with minimum power without any rate reduction. Numerical results from simulations are given to support the mathematical development of the problem.