基于稀疏互质阵列的DOA估计算法研究

This project mainly deals with the estimation problem of DOA for signal sources and scattering sources by using the sparse and non-uniform coprime receiving array as well as the sparse and uniform coprime transmit-receiving array respectively. The theory for DOA estimation with coprime array can be improved via the studies of the coarray theory of coprime array, the augmentation method of autocorrelation matrix, the DOA estimation algorithm and the performance evaluation system of the related theories and algorithms. We will solve the key technologies, and propose the estimation algorithms for target DOA which make full use of the degrees of freedom from the coprime layout. We will validate, analyze and optimize the theoretical achievements with the simulation data. The research of this project can increase the number of the resolvable signal sources and scattering sources to break the limitation of the number of physical array elements. Moreover, the flexibility of DOA estimation is introduced to the scattering sources. Therefore, it is of great theory significance and application worth to provide the technical basis for the applications of coprime array and theory system in Radar and sonar (enhance the ability of target acquisition), and communication (improve the channel capacity).

本项目旨在利用稀疏非均匀的互质接收阵列和稀疏均匀的互质收发阵列分别解决信号源和散射源两类目标DOA的估计问题，通过对互质阵列协同阵理论、多频自相关矩阵增广方法、DOA估计算法、相关理论与算法性能评估体系等方面的研究，完善基于互质阵列的DOA估计理论体系。突破关键技术难题，提出充分利用互质布局自由度实现目标DOA估计的算法，利用仿真数据对研究取得的理论成果进行验证、分析及优化。本项目的研究可提高对信号源和散射源DOA估计的最大可分辨目标数，突破物理阵元数的限制，还可带来散射源DOA估计的灵活性，为互质阵列及其理论体系在雷达与声呐（加强目标捕获能力）、通信（提升信道容量）等领域的应用奠定技术基础，具有重要的理论意义和应用价值。

本项目将非均匀稀疏互质布局引入到阵列DOA估计中，实现了对超出物理阵元数目的目标进行分辨。通过对互质阵列协同阵理论、自相关矩阵增广方法、多频阵列扩充方法、DOA估计算法等方面的研究，提出了基于伪波束形成的互质接收阵列非相干源DOA估计算法、基于多频工作的互质接收阵列非相干源DOA估计算法、基于矩阵重构的互质接收阵列相干与非相干混合信号源DOA估计算法、基于“和协同阵等效”的互质MIMO阵列相干与非相干混合目标DOA估计算法、基于相关矩阵重建解相干的MIMO互质阵列DOA估计算法、双基互质MIMO阵列DOD与DOA联合估计算法、基于互质双频的均匀稀疏接收阵列和稀疏嵌套MIMO阵列DOA估计算法，完善了基于互质阵列的DOA估计理论体系。本项目研究成果能够提高目标DOA估计的最大可分辨目标数，使其突破物理阵元数的限制，还可带来目标DOA估计的灵活性，有助于提升雷达与声呐等阵列系统的目标捕获能力，具有重要的理论意义和应用价值。