部分信道状态信息下多天线系统的最优发送

在实际的单用户多天线平坦衰落通信系统中,接收端往往具有理想的信道状态信息,而发送端只有来自接收端的部分信道状态信息反馈,因此在发送端信道模型假设为复高斯随机矩阵.在发射端具有信道协反差反馈或者均值反馈的情形下,对达到最大的信道容量即信息论角度的最优化问题进行了理论分析,研究了系统的最优发送方案.对目前的关于单方向发射的最优条件进行扩展,进一步推导了沿任意多个方向发送达到信道容量的条件.数值结果验证了分析结论.

Transmitter optimization in multiple antenna systems with partial channel state information

In realistic single-user multiple-antenna flat-fading communication system, the receiver has usually perfect channel state information (CSI), while the transmitter has only partial channel state information feedback from the receiver, and the channel is modeled at the transmitter as a complex Gaussian random matrix. This paper analyzes theoretically the problem of achieving channel capacity in the perspective of information theoretical optimization, and discusses the transmitter optimization strategy, under the cases of covariance feedback and mean feedback. Current discussion of optimization with single direction is extended to the general case, and conditions for achieving capacity with arbitrary number of transmitting directions are derived. Numerical results verify the conclusions.