针对传统多输入多输出(Multiple-Input Multiple-Output,MIMO)系统下信道反馈开销大、发送端的最优预编码设计难以实现的问题,研究有限信道状态信息(Channel State Information,CSI)反馈下的联合预编码设计与码字搜索技术,提出一种基于...针对传统多输入多输出(Multiple-Input Multiple-Output,MIMO)系统下信道反馈开销大、发送端的最优预编码设计难以实现的问题,研究有限信道状态信息(Channel State Information,CSI)反馈下的联合预编码设计与码字搜索技术,提出一种基于离散傅里叶变换(Discrete Fourier Transform,DFT)码本的快速码字搜索算法。该算法利用MIMO信道天然具有的信道硬化特性,将理论性能最优但是计算复杂度极高的遍历式码字搜索算法转化为求解多个简单优化问题的快速码字搜索算法。仿真结果显示,该算法能够在性能损失较小的情况下大幅度降低码字搜索的计算复杂度。展开更多
The discrete Fourier transform （DFT）-based codebook is employed in this paper to quantize channel state information so that the amount of feedback can be reduced in the multiple input multiple output （MIMO） downli...The discrete Fourier transform （DFT）-based codebook is employed in this paper to quantize channel state information so that the amount of feedback can be reduced in the multiple input multiple output （MIMO） downlink of long term evolution （LTE） system. And a novel beamforming （BF） scheme based on the proposed channel quality-to-interference （QIR） quantizing criteria is developed, which uses only the index of the optimal codebook for the beamforming at the base station （BS）, and dramatically reduces the amount of feedback. The proposed BF scheme jointly considers the influences of the quality of the quantized channels and the mutual interference among the sub-channels. The extensive simulation results verify that throughput of the proposed BF scheme is better than that of the random BF with a little feedback, and that of the eigen-beamforming even under low signal noise ratio （SNR） scenario.展开更多
基金supported by the Program for New Century Excellent Talents in University (NCET-08-0891)the Research Fund for the Doctoral Program of Higher Education of China(20070532077)the Natural Science Foundation of Shaanxi Province (2010JQ80241, 1090275)
文摘The discrete Fourier transform （DFT）-based codebook is employed in this paper to quantize channel state information so that the amount of feedback can be reduced in the multiple input multiple output （MIMO） downlink of long term evolution （LTE） system. And a novel beamforming （BF） scheme based on the proposed channel quality-to-interference （QIR） quantizing criteria is developed, which uses only the index of the optimal codebook for the beamforming at the base station （BS）, and dramatically reduces the amount of feedback. The proposed BF scheme jointly considers the influences of the quality of the quantized channels and the mutual interference among the sub-channels. The extensive simulation results verify that throughput of the proposed BF scheme is better than that of the random BF with a little feedback, and that of the eigen-beamforming even under low signal noise ratio （SNR） scenario.
