基于ESPRIT的均匀互耦线阵DOA及互耦参数估计

利用均匀线阵的特殊结构及其互耦矩阵,提出了一种阵列互耦存在下基于ESPRIT的DOA和互耦参数估计方法.首先通过ESPRIT法中子阵的选取,无需阵列互耦任何信息,直接得到方位估计,即对互耦参数稳健的DOA估计方法;接着在方位估计的基础上,基于真实导向矢量的最小方差拟合得到均匀线阵的互耦系数估计.与已有算法相比,该算法同时利用了天线阵列结构及其互耦特点,一方面将信号角度与互耦系数估计相互分离,使角度估计精度不受互耦估计的制约;另一方面,方位和互耦系数估计均可通过表达式求解,因此算法运算量小.计算机仿真证明该算法的有效性和正确性,并从仿真角度研究了算法分别在幅相误差和互耦矩阵误差下的性能.

ESPRIT-based DOA and mutual coupling estimation of ULA

Based on the special structure of the uniform linear array(ULA) and its mutual coupling matrix,an ESPRIT-based DOA and mutual coupling estimation method is proposed.By a smart choosing of sub-array for ESPRIT,DOA is estimated directly without the value of the mutual coupling matrix,which can be seen as a robust DOA estimation based on ESPRIT.Then mutual coupling parameters are obtained via the least squares(LS) fitting of the actual steering vectors.Compared with existing algorithms,the structure of array and its mutual coupling characteristic are explored simultaneously in this method.The DOA and mutual coupling parameters are estimated separately,and the DOA estimation precision is not limited to the mutual coupling parameters estimation.Then,the DOA and mutual coupling parameters are both calculated from corresponding expressions,and neither searching nor iterating brings the method a less computational load.In the end,computer simulations demonstrate the effectiveness of the proposed method and the performances under the phase error and the mutual coupling matrix error respectively.