In this letter, we propose a new method for two-dimensional (2-D) direction-of-arrival (DOA) estimation using two parallel nested arrays. In this method, an augmented covariance matrix is firstly constructed using the outputs of two parallel difference coarrays. Based on the augmented covariance matrix, the 2-D DOA estimation problem is then converted into two one-dimensional estimation problems. Finally, the azimuth and elevation angle estimates are derived using the estimated direction cosines. Unlike the traditional methods, our algorithm exploits the difference coarray to increase the array aperture and degrees of freedom. Moreover, it does not require any peak searching and can achieve parameter automatic pairing. Numerical simulations are conducted to verify the performance of the proposed method.

中文翻译：

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使用两个平行嵌套阵列的二维 DOA 估计

在这封信中，我们提出了一种使用两个并行嵌套阵列进行二维 (2-D) 到达方向 (DOA) 估计的新方法。在该方法中，首先使用两个并行差分协阵列的输出构造增广协方差矩阵。然后基于增广协方差矩阵，将二维 DOA 估计问题转换为两个一维估计问题。最后，方位角和仰角估计是使用估计的方向余弦导出的。与传统方法不同，我们的算法利用差分共阵列来增加阵列孔径和自由度。此外，它不需要任何峰值搜索，可以实现参数自动配对。进行数值模拟以验证所提出方法的性能。