Power Allocation without CSI Feedback for Decision-Feedback MIMO Signal Detection

Transmit and receive antenna arrays can be used to form multiple-input and multiple-output (MIMO) systems for improving the reliability and capacity of data transmission. Layered space-time coding with decision-feedback detection is a promising technique for future wireless communications. In this paper, we investigate power allocation at the transmitter to improve the performance of the decision-feedback detection. The proposed power allocation method may only depend on or is even independent of the signal-to-noise ratio (SNR) of the MIMO systems. When the SNR at the transmitter is not available, the power of each data stream is allocated according to the required bit-error-rate (BER) of the system. Computer simulation shows that the proposed method can improve the performance of a 2-input and 2-output system by 4 dB at 1% BER and that of a 4-input and 4-output system by 3.5 dB.