非圆信号二维DOA和初始相位联合估计算法

为了充分利用非圆信号共轭相关不为零的特性，提高空间到达角（direction of arrival，DOA）和极化参数估计精度，提出了一种信号DOA和极化参数估计的稳健算法.即构造2个非圆信号的4阶累积量矩阵，引入旋转不变子空间（estimation of signal parameters via rotational invariance techniques，ESPRIT）算法思想，利用这2个矩阵之间的旋转不变特性求出旋转因子，实现信号DOA和极化参数更精确估计.与2阶相域ESPRIT相比，改进的算法适用于任意极化状态的信号，提高估计信号的利用率，同时利用4阶累积量对高斯噪声的抑制性处理相关噪声，使估计信号的精度有了明显提升，并通过仿真结果验证了改进算法的有效性.

Joint 2-D DOA and noncircularity phase estimation method

To take full advantage of the non-circular conjugate signal being not zero correlation characteristics, improve the direction of arrival (DOA) and the accuracy of parameter estimation, a robust algorithm DOA and polarization estimation was proposed. First, two fourth-order cumulant matrix of non-circular signals were constructed, then the estimation of signal parameters via rotational invariance techniques (ESPRIT) algorithm thinking was introduced, and the rotation operator was obtained using these two rotational invariance relationship matrices to achieve signal DOA and polarization estimation. Compared with the second-order phase domain ESPRIT, the improved algorithm applies to arbitrary polarization state of the signal, improve the utilization of the estimated signal and take advantage of Gaussian noise suppression of fourth-order cumulate (FOC) to process the related noise, so that the accuracy of the estimate signal has improved significantly, and the simulation results show the effectiveness of the improved algorithm.