Real-Valued Near-Field Localization of Partially Polarized Noncircular Sources with a Cross-Dipole Array

In this paper, a novel near-field localization algorithm is proposed for partially polarized noncircular sources. The algorithm is composed of two stages. In the first stage, based on the cross-dipole, the array observations are transformed into the real-valued domain. Then, an extended covariance matrix is constructed and the structure of the real-valued steering vector is utilized to factorize the direction of arrival (DOA) parameter from other parameters. Based on the rank reduction (RARE) principle, the DOA parameters can be obtained through the one-dimensional (1-D) spectral search. In the second stage, with the DOA estimates, the range parameters are generated via another RARE estimator, which also only requires a 1-D spectral search. Compared with the conventional second-order statistics (SOS)-based methods, the proposed algorithm is computationally more efficient since it only requires 1-D spectral search and real-valued computations. Moreover, it can resolve more sources and promote the DOA estimation accuracy. Numerical simulation results corroborate the effectiveness and efficiency of the proposed method.