Three-Level Prime Arrays with Compressed Subarray for DOA Estimation Using Compressive Sensing
Saleh A. Alawsh, Ali Hussein Muqaibel · 2019
Nowadays, designing an antenna array that can estimate the direction of arrival (DOA) for large number of sources greater than the number of elements has received a lot of interest. This can be realized by relying on the difference coarray. The realizable degrees of freedom (DOF), which determines the number of sources to be estimated, depends on the virtual antenna locations appear in the difference coarray rather than the array physical elements locations. The presence of missing lags "holes" in the difference coarray leads to less virtual antenna locations. This paper proposes a three-level prime array with compressed subarray (3LPAC) that combines three uniform linear subarrays. The number of antenna elements in the subarrays are pairwise coprime integers. The spacing of one subarray is reduced to maximize the number of consecutive lags. The inter-element spacing of the remaining two subarrays equal to the number of antenna elements of another subarray scaled by half-wavelength. A closed form expression for the antenna locations is derived. The proposed configuration can realize a hole-free difference coarray. Simulation results with examples for difference coarray and DOA estimation validate the effectiveness of the 3LPAC using compressive sensing (CS).