In this paper, we investigate the issue of direction-of-arrival (DOA) estimation of multiple signals in coprime arrays. An algorithm based on multiple signal classification (MUSIC) and forward and backward spatial smoothing (FBSS) is used for DOA estimation of this signal caused by multipath and interference. The large distance between adjacent elements of each subarray in the coprime arrays will bring phase ambiguity issues. According to the feature of the coprime number, the ambiguity problem can be eliminated. The correct DOA estimation can be obtained by searching for the common peak of the spatial spectrum and finding the overlapping peaks in the MUSIC spectrum of the two subarrays. For the rank deficit problem caused by the coherent signal, the FBSS algorithm is used for signal preprocessing before the MUSIC algorithm. Theoretical analysis and simulation results show that the algorithm can effectively solve the rank deficiency and phase ambiguity problems caused by coherent signals and sparse arrays in the coprime arrays.

中文翻译：

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Coprime 阵列的相干目标到达方向估计：从空间平滑的角度来看

在本文中，我们研究了互质阵列中多个信号的到达方向 (DOA) 估计问题。基于多信号分类 (MUSIC) 和前向和后向空间平滑 (FBSS) 的算法用于对该信号由多径和干扰引起的 DOA 估计。互质阵列中每个子阵列的相邻元素之间的大距离会带来相位模糊问题。根据互质数的特点，可以消除二义性问题。正确的 DOA 估计可以通过搜索空间谱的共同峰值，并在两个子阵列的 MUSIC 谱中找到重叠的峰值来获得。针对相干信号引起的秩亏问题，在MUSIC算法之前采用FBSS算法进行信号预处理。