The problem of manifold ambiguity-free direction-of-arrival (DOA) estimation for an unfolded co-prime array is of prime research interest. The manifold ambiguity problem is resolved by using beamforming-like methods. However, the performance of this method is limited by the searching step, computational complexity and also fails to resolve the closely spaced sources. In order to overcome the above limitations, in this letter, the DOA estimation is viewed as a function approximation problem. The unknown mapping function that relates the received signals and its DOAs is approximated by using the support vector regression (SVR). The proposed method resolves the ambiguity problem completely with low computational complexity. The simulation results are provided to validate the superiority and effectiveness of DOA estimation in terms of estimation accuracy, computational complexity and reliability.

中文翻译：

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用于展开共素阵列的流形无歧义低复杂度 DOA 估计方法

展开的互质阵列的流形无歧义到达方向 (DOA) 估计问题是主要研究兴趣。流形模糊问题是通过使用类似波束成形的方法解决的。然而，该方法的性能受到搜索步骤、计算复杂度的限制，并且无法解决紧密间隔的源。为了克服上述限制，在这封信中，DOA估计被视为一个函数逼近问题。通过使用支持向量回归 (SVR) 来近似与接收信号及其 DOA 相关的未知映射函数。该方法以较低的计算复杂度完全解决了歧义问题。