Efficient Method of Passive Localization for Mixed Far-Field and Near-Field Sources
An effective second-order statistics (SOS)-based algorithm is addressed for scenarios where both far-field and near-field narrowband sources may exist simultaneously. After estimating the direction-of-arrivals (DOAs) and powers of far-field signals, the related far-field components can be eliminated from the signal subspace. Then, based on the symmetric property of the uniform linear array geometry, a near-field estimator without two-dimensional search or parameter pairing is performed. Compared to the previous SOS based method, the resultant algorithm can provide an improved estimation accuracy, as well as realize a more reasonable classification of the signal types. Simulation results are carried out to demonstrate the performance of the proposed algorithm.