互质阵列是近年来兴起的新型阵列,能显著提高阵列自由度,处理信源数大于阵元数时的波达方向(DOA)估计,且能提高角度分辨率和测角精度。文中根据互质阵物理阵元和虚拟阵元特点,结合多重信号分类(MUSIC)算法提出适用于互质阵基于物理阵列和虚拟阵列的DOA估计方法。该方法以非相干信号源为研究对象,利用互质阵列建立信号接收模型,基于物理阵列的DOA估计方法根据互质阵物理阵元位置特点推导其导向矢量,然后根据导向矢量计算回波信号数据和信号协方差矩阵,最后利用MUSIC算法进行DOA估计。基于虚拟阵列的DOA估计方法根据其虚拟阵元数据特点在向量化协方差矩阵并去冗余后选取连续虚拟阵元接收数据,然后对新协方差矩阵进行一维Toeplitz平滑重构,最后利用MUSIC算法或求根MUSIC算法进行DOA估计。与等阵元数的均匀线阵进行对比,仿真实验验证了互质阵列DOA估计性能的优越性。

Coprime array is a new type of array rising in recent years. It can significantly improve the freedom degree of the array, deal with the direction of arrival (DOA)estimation when the number of sources is greater than the number of array elements, and improve the angle resolution and angle measurement accuracy. According to the characteristics of physical array elements and virtual array elements of coprime array, combined with multiple signal classification (MUSIC) algorithm, a DOA estimation method based on physical array and virtual array for coprime array is proposed in this paper. In the method, the incoherent signal source is taken as the research object, the signal receiving model is established by using coprime array, the DOA estimation method based on physical array is used to deduce its guidance vector according to the position characteristics of coprime array physical array elements, then the echo signal data and signal covariance matrix are calculated according to the guidance vector, and finally MUSIC algorithm is used to estimate DOA. According to the characteristics of virtual array metadata, the DOA estimation method based on virtual array selects continuous virtual array elements to receive data after vectorizing the covariance matrix and removing redundancy, then carries out one-dimensional Toeplitz smooth reconstruction of the new covariance matrix, and finally uses MUSIC algorithm or root MUSIC algorithm for DOA estimation. Compared with the uniform linear array with equal array elements, simulation experiments verify the superiority of DOA estimation performance of coprime array.

TN957.51

国家自然科学基金资助项目