多输入多输出(MIMO)系统中,天线选择技术可以在降低复杂度的同时,有效地提高系统的性能.但对于天线安装空间受限的小型终端,天线的数目将受到很大限制,本文结合方向图可重构技术,考虑基于线性接收机的空间复用系统,通过在已选择的发射天线上采用等功率分配等增益传输以减少反馈信息量.在此条件下,推导出空间相关衰落信道下自适应发射天线选择的统计容量公式下限,然后,在此基础上提出基于方向图重构的发射天线快速选择方法以最大化该容量值.此外,在实现中提出了一种基于滑动时间窗的梯度更新估计模型,缩短了算法所需时间.%In a wireless multiple-input multiple-output (MIMO) system,transmit antenna selection is an effective means of achieving good performance with low complexity. However, the space for the antenna array is usually limited on wireless terminal.Hence, antenna' s configurable pattern selection is considered to save space, using spatial multiplexing with linear receivers, and equal power and equal rate allocation to reduce feedback overhead. Under these constraints, a statistical adaptive transmit antenna pattern selection is studied to improve the capacity of spatially correlated MIMO fading channels. Then, we propose a fast transmit antenna pattem subset selection criterion based on maximizing this average lower-bound capacity. More over, in order to catch up the channel variant in low speed moving environment in a real transceiver, we also propose a refreshed gradient estimation method based on sliding time window. And the measured result indicates that the method reduces the searching time of reconfigurable patterns selection.
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