基于矢量线性运算的自适应球帽差分反馈算法

Adaptive Spherical-cap Differential Feedback Algorithm Based on Linear Operations of Vectors

信道时间相关多输入多输出(MIMO)系统中一种重要有限反馈策略为差分反馈,该文提出一种适用于单用户多输入单输出(SU-MISO)系统的自适应球帽差分反馈算法。首先,介绍基于信道扰动规律的自适应差分反馈策略;其次,给出一种基于矢量线性运算的差分码本构造方法,它不需要对基码字每个元素进行单独操作,易于计算及生成;最后,运用一阶高斯马尔可夫链信道模型下前一时刻信道方向、选定码字及当前时刻信道方向的随机空间分布规律,给出一种球帽码本半径计算方法。仿真结果说明,该算法能准确跟踪信道并较现有算法有一定性能提高。

In the MIMO systems, the differential feedback is an important strategy for temporally correlated channels. A new adaptive spherical-cap differential feedback algorithm is proposed for the Single-User Multiple Input Single Output （SU-MISO） systems. Firstly, this study introduces the adaptive differential feedback strategy from the perspective of the channels disturbance. Secondly, based on vectorslinear operation, one design method of the spherical-cap differential codebook is proposed, which no need to perform operation for each element of based-codewords and is easier to construct. Finally, for the first-order Gauss-Markov Process channel, considering the spatial random distribution among the channel directions at two consecutive time instants and the selected codeword at previous instant, one calculation method of spherical-cap radius is given. The simulation results show that the proposed algorithm can accurately track the channel disturbance and has certain performance improvement than the existing algorithms.