Near-field source localization via sparse subarrays

This paper presents a novel extended aperture ESPRIT (EAESPRIT) algorithm for near-field sources localization via a sparse dual-size linear array. By constructing a cumulant matrix with only direction-of-arrival (DOA) information, the proposed algorithm decouples the DOA estimation from the range estimation. The cumulant-domain quarter-wavelength invariance yields unambiguous estimates of DOAs, which are then used as coarse references to disambiguate the phase ambiguities in fine estimates induced from the larger spatial invariance. With the estimated DOAs, range estimations are produced by searching on the one-dimensional range spectrum. Compared with some existing algorithms, the proposed algorithm enjoys extended array aperture and higher estimation accuracy. Simulation results are presented to validate the improvement in the performance of the proposed algorithm.