Mixed Near-Field and Far-Field Source Localization Based on Uniform Linear Array Partition

Based on the polynomial decomposing method and high-order cumulant technique, a novel localization algorithm for the mixed near-field (NF) and far-field (FF) sources is proposed by using a uniform linear array (ULA). First, the ULA is divided into two sub-arrays, with different phase reference points. Three special fourth-order cumulant matrices are designed to eliminate the range parameters of the NF sources in the steering vectors, which only contain the direction of arrival (DOA) information. Second, based on the ESPRIT algorithm, the DOA of each source at the phase reference point is estimated. Third, with the DOA estimation, the type of the sources is classified by computing its coefficient matrix. Finally, the range parameters of NF sources and the DOAs of FF sources are captured. The proposed algorithm does not require any spectral search, which leads to low computational complexity. Moreover, this algorithm avoids the parameter matching procedure. Numerical experiments are conducted to verify the effectiveness of the proposed algorithm.