基于多波束训练的毫米波信道混合预编码方法

Hybrid Precoding Method Based on Multi-Beam Trainings for Millimeter-Wave Channels

无线毫米波通信具有大量可用带宽,为了降低系统成本和功耗,又支持多个数据流传输,提出了一种采用多波束训练和迭代更新的方式设计无线毫米波信道混合预编码器的方法。为了最大化频谱效率,所提方法首先采用多波束训练的方式估计信道主要来波角度并形成备选波束集合;其次,采用迭代更新的方式优化设计射频域模拟预编码器;根据已经确立的等效信道,建立频谱效率满足一定限制条件下的凸优化数学模型并进行求解,从而确立最优的等效信道和数字基带预编码器。数值仿真与实验结果表明,在用户信道相似度较高的情况下,所提方法具有比现有混合预编码方法更优的频谱效率。

Millimeter-wave communication systems have a large number of available frequency bands.In order to support multiple streams and reduce power consumption and cost,a hybrid precoder design method based on multi-beam training and iterative updating is proposed for millimeter-wave channels.In order to maximize the spectrum efficiency,the proposed method first utilize multi-beam trainings to estimate the angle of arrivals of the dominant paths of the channels and form the alternative beam collection.Then,the analog precoder is iteratively updated to find the optimal paths of the user channels.Furthermore,based on the determined equivalent channel,the digital precoder is determined by establishing the convex optimal mathematical model and solving the objective function on the condition that the spectrum efficiency should exceed the given threshold.The numerical and experimental results show that the spectrum efficiency of the proposed method is superior to those of existing hybrid precoding algorithms in highly correlated channels.