存在反馈延迟的短波MIMO预编码系统设计

Feedback delay in precoding MIMO system within the HF band

利用基于码本的预编码MIMO技术去提升短波通信的空间分集增益,短波天波信道利用电离层的一次或多次反射进行远距离通信,信号传播延时较大,为了消除反馈延时对预编码MIMO系统性能的影响,文中基于Kalman滤波器提出一种信道估计与预测模型,自适应地跟踪短波时变信道,接着根据ITS短波时变信道模型提取信道时域特征,估计出预测模型参数,通过与传统无信道预测的预编码方案进行对比,方案能够有效降低反馈延迟对短波MIMO预编码系统性能的影响。

This paper uses a codebook-based precoding MIMO technique to obtain the space diversity gain of HF communication. The sky-wave channel uses one or more reflection of the ionosphere to communicate at a distance, resulting in large signal propagation delay. In order to eliminate the influence of feedback delay of precoding MIMO system, the paper proposes a channel estimation and prediction model based on Kalman filter, adaptive tracking shortwave time-varying channel, then according to ITS shortwave time-varying channel model extract channel time-domain features, estimates the prediction model parameters. Compared to the traditional precoding scheme without channel prediction, this scheme can effectively reduce the feedback delay effects on HF MIM0 precoding system performance.