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A vector-hydrophone (a.k.a. acoustic vector-sensor) is composed of two or three spatially collocated but orthogonally oriented velocity-hydrophones, possibly plus a collocated pressure-hydrophone. A vector-hydrophone may form azimuth-elevation spatial beams that are invariant with respect to the sources’ frequencies, bandwidths and radial locations (i.e., in near field as opposed to the far field). This paper adopts a multiple-forgetting-factor recursive-least-squares (RLS) adaptive algorithm to a single vector-hydrophone for source tracking, without needing any prior knowledge of the source power and/or the noise powers.