面向全维MIMO系统的空间域选择预编码方法研究

全维MIMO（FD-MIMO）是下一代移动通信关键技术之一，低复杂度、高频效的预编码技术对于FD-MIMO系统至关重要。Kronecker积预编码技术因较低的硬件和计算复杂度而极具吸引力，然而其理论研究尚不完善，亟待进一步加强。本项目拟分析Kronecker积预编码水平和垂直域内在联系，提出空间域选择机制以提升预编码性能。具体内容包括：（1）在基于瞬时信道信息的预编码中，利用降维思想分析水平和垂直域预编码的耦合关系，建立空间域选择机制，并以提升频效为目标，选择域（水平或垂直域）进行预编码；（2）基于统计信道信息，利用空间域选择机制，并提出利用全信道空间的预编码方法，以兼顾系统开销和频效；（3）在基于Kronecker积的预编码和均衡器联合设计问题中，利用张量理论，研究空间域选择联合设计方法以提升频效。该项目研究对于丰富FD-MIMO预编码技术内涵、推动FD-MIMO系统应用具有重要意义。

Full dimension MIMO (FD-MIMO) is one of the key technologies for next-generation mobile communications. It is critically important for FD-MIMO to design a precoding scheme with low-complexity and a high spectral efficiency. Kronecker product precoding technology is extremely attractive due to its low hardware and computational complexity, but its theoretical research is not enough and needs to be further strengthened. This project intends to analyze the internal relationship between the azimuthal and elevational precodings of Kronecker product precoding and intends to propose a spatial domain selective scheme to improve precoding performance. The specific contents include: (1) In the precoding based on instantaneous channel information, the idea of dimensionality reduction is used to analyze the coupling relationship between the azimuthal and elevational precodings, and a spatial domain selective scheme is established. To improve the spectral efficiency, different domains (the azimuthal and elevational domain) are selected to precode; (2) Based on the statistical channel information, the spatial domain selective scheme is used, and a precoding method utilizing full channel space is proposed to consider both the system overhead and spectral efficiency; (3) Tensor theory is used to analyze the joint designing problem of precoding and equalization based on Kronecker product, and a joint design method based on spatial domain selective scheme is proposed to improve the spectral efficiency. The research of this project is of great significance to enrich the connotation of FD-MIMO precoding technology and promote the application of FD-MIMO system.