基于均匀圆阵的Toeplitz解相干DOA估计算法

An Improved Toeplitz Decorrelation Algorithm for DOA Estimation with Uniform Circular Array

针对均匀圆阵的DOA估计,提出了一种改进的Toeplitz解相干DOA估计算法。该算法利用模式空间变换算法,将均匀圆阵变为虚拟均匀线阵,在此基础上利用接收数据协方差矩阵的行、列分别构造Toeplitz矩阵并取均值,以此来改变协方差矩阵的数据结构,使协方差矩阵的秩得到有效恢复,完成相干信号的DOA估计。由于该算法充分利用了协方差矩阵的信息,相当于一次双向平滑处理过程,较之传统的模式空间平滑类算法(MODE-FBSS)和模式空间矩阵重构算法(MODE-TOEP),减少了误差和噪声对阵元的影响,提高了算法的估计性能。理论证明和仿真实验验证了该算法的可行性和有效性。

An improved Toeplitz decorrelation algorithm (MODE-TDM) is proposed for the DOA estimation of coherent signals on a Uniform Circular Array (UCA). Firstly, the mode excitation method is used to tran- sform the UCA in element space into a virtual ULA (VULA) in mode space. Then using every row elements and corresponding every column elements of array covariance matrix of VULA to construct two Toeplitz matrixes, a new covariance matrix is obtained taking average these two matrixes. This process is equivalent to the forward-backward smoothing technology and reduces the influence of the array error and noise. Lastly, combined with ESPRIT algorithm, it is capable of resolving the DOAs of coherent signals without peak searching. Theoretical analysis and simulation results demonstrate this algorithm has better performance and less estimated time compared with conventional MODE-FBSS algorithm and MODE-TOEP algorithm.