Near-field Source Location Estimation Algorithm Based on Coprime Array

Abstract

For the problems of uniform linear array (ULA) that the number of detection signals is limited by the number of array elements, and the array spacing is limited by half-wavelength, this paper proposes a near-field source location estimation method based on coprime arrays. The proposed method preprocesses the data received by the coprime array to establish an off-grid model that only contains angle parameters, and direction of arrival (DOA) estimation of incident signal is obtained by iterative method. By fixing the estimated angle, this paper constructs a distance parameter off-grid model, and distance estimation is obtained by the iterative method. At the same time, the estimated angle and the estimated distance are matched to determine the source position. Theoretical analysis and experimental results demonstrate that the method in this paper enlarges the array aperture, effectively improves the estimation accuracy of DOA and distance, and still has good estimation performance under the condition of low signal-to-noise ratio or small snapshots.