一种稳健的非圆信号波达方向估计算法

Robust direction finding algorithm for non-circular signals

为了充分利用非圆信号的特性,提高非圆信号波达方向估计的性能,针对最大非圆率信号,提出了一种稳健的波达方向估计算法。首先,构造两个包含信号非圆信息的四阶累积量矩阵;然后,利用这两个矩阵的旋转不变关系实现信号的波达方向估计;最后,在存在通道幅相误差模型下分析了算法的稳健性,并推导出只要令接收通道中任意两个通道保持一致,算法就能得到正确的波达方向估计。仿真实验表明,算法的测角精度得到提高,并且算法对通道幅相误差具有稳健性。

In order to make full use of the characteristics of non-circular signals and improve the performance of direction finding algorithms for non-circular signals, a robust direction finding algorithm for non-circular signals with maximum non-circularity rate is presented. Firstly, two fourth order cumulant matrixes which contain the information of non-circular signals are constructed. Secondly, the direction of signals by the rotational invariance correlation between the two matrixes are estimated. Finally, the robustness of the algorithm is analysed in the model with amplitude and phase errors. The correct direction of arrival estimation would be obtained by the proposed algorithm, as long as any two of the channels maintaining consistent processing. Simulation results show that the angular precision of the algorithm has been improved and the algorithm is robust to the channel mismatch.