DOA Estimation for 2D Multi-level Dilated Nested Array

A new multi-level dilated nested array in two dimensions called 2D multi-level DiNA, which further improves the direction of arrival (DOA) estimation performance of 2D nested array, is proposed. The proposed array consists of an original 2D nested array and one or more time-delay arrays, and is suitable for the cases in which the sensing environment can be assumed stationary during array motion. The difference co-array of 2D multi-level DiNA is hole-free and the number of the degrees-of-freedom (DOFs) is several times more than that of 2D nested array. Therefore, for the DOA estimation, 2D multi-level DiNA can detect more sources and achieve more accurate estimation performance compared with the original 2D nested array. Numerical simulations are performed to verify the superiority of the proposed 2D multi-level DiNA.