MIMO)信道固有的空时相关性对采样得到的信道状态信息(Channel State Information
CSI)进行矩阵重排和数据平滑处理
随后基于信道的多维结构特性
使用HOSVD降低噪声的影响
继而重构信道矩阵
最后利用递归最小二乘滤波器对未来时刻的信道状态进行预测.仿真表明
所提算法的估计误差和预测误差性能均明显优于对比算法
这是因为所提算法通过矩阵重排和空时平滑
虚拟地增加了天线数
降低了秩缺失问题对估计和预测精度的影响
从而有效补偿了因误差所致的信道容量的损失.同时
对比天线数和多普勒频移对不同算法性能的影响可见
所提算法也能在大多普勒频移和天线数较少等不利条件下提供较好预测性能和信道容量
具有一定的优越性.
Abstract
Channel prediction algorithm based on high order singular value decomposition (HOSVD) denoising is sensitive to the small number of antennas and cannot cope with the maximum Doppler shift
which may result in a sharp drop in the channel estimation and prediction performance and the loss of channel capacity. To solve this problem
this paper proposes an improved channel prediction algorithm based on HOSVD denoising. The proposed algorithm first smoothes the sampled channel state information (CSI) by using the space-time correlation inherent in the multiple-input multiple-output channel
and then uses HOSVD to reduce the influence of noise and reconstruct the channel matrix based on the multi-dimensional structure characteristics of the channel. Finally
the recursive least squares filter is used to predict future CSI. Simulation results show that the channel estimation error and the prediction error of the proposed algorithm were better than those of the comparison algorithm. This is because the proposed algorithm uses matrix rearrangement and space-time smoothing to increase the number of antennas virtually
which can effectively reduce the influence of the Doppler shift factor and the rank missing problem caused by the small number of antennas on the prediction accuracy
thus compensating the loss of channel capacity. At the same time
by comparing the influence of antenna number and the Doppler frequency shift on the performance of different algorithms
it can be found that the proposed algorithm could provide better prediction performance and channel capacity under unfavorable conditions such as Doppler frequency shift and few antennas