DOA estimation method of spatial spectrum product for distributed coprime linear array

Coprime array is A sparse array composed of two uniform linear arrays with different spacing. When the two subarrays are in A non-coherent distributed configuration, the direction of arrival (DOA) method based on the covariance analysis of the complete coprime array is no longer effective. According to the essential attribute that the distance between the elements of two subarrays can eliminate the angle ambiguity, based on the mathematical derivation, A spatial spectral product DOA estimation method for incoherent distributed coprime arrays is proposed. Firstly, the spatial spectrum of each subarray is calculated by using the snapshot data of each subarray, and then the DOA estimation is realized by multiplying the spatial spectrum of each subarray. The simulation results show that the estimation accuracy and angle resolution of the present method are better than those of the traditional ambiguity resolution methods, and the estimation performance is good in the mutual coupling and low SNR environment, with the good adaptability and stability. Moreover, by using the flexibility of distributed array, the matching error is effectively solved through the rotation angle. 互质阵是由2个不同间距的均匀线阵组成的稀疏阵，当两子阵处于非相参分布式配置时，基于完整互质阵协方差分析的众多波达方向（direction of arrival，DOA）估计方法不再有效。根据两子阵阵元间距互质可消除角度模糊的本质属性，在数学推导基础上，提出一种适用于非相参分布式互质阵的空间谱乘积DOA估计方法，利用各子阵快拍数据分别计算子阵空间谱，将子阵空间谱进行乘积实现DOA估计。仿真结果表明，所提方法估计精度及角度分辨率均优于传统解模糊方法，在互耦及低信噪比环境下估计性能良好，具有很好的适应性和稳定性。且利用分布式阵列的机动灵活性，通过转角有效解决了匹配错误问题。