Dual-Sparse Parallel Nested Array for Two-Dimensional Direction of Arrival Estimation

In this paper, a novel dual-sparse parallel nested array (DS-PNA) is proposed for high-accuracy two-dimensional (2D) direction of arrival (DOA) estimation. The DS-PNA contains three subarrays, and the inter-antenna spacings of subarrays and those between subarrays are all enlarged with specific rates in 2D space (both of which are far larger than half-wavelength), for mutual coupling reduction and array aperture extension in physical array domain. Based on it, there is a systematic procedure to determine the number and positions of antennas in each subarray to achieve the maximum degrees of freedom in difference coarray domain, for improving the performance of DOA estimation. Numerical results are provided to demonstrate the superior performance of the DS-PNA for 2D DOA estimation over the state-of-the-art approaches, in the case of practical mutual coupling model.