Estimating source position accuracy of a large-aperture hydrophone array for bioacoustics

A linear error propagation analysis was applied to a hydrophone array used to locate sperm whales [see Mohl ct nl., J. Acoust. Sec. Am. 107, 638-648 ( 2000)]. The accuracy of two-dimensional (2D) and three-dimensional (3D) an ay configurations was investigated. The precision in source location was es timated as a function of inaccuracies in measurements of sound velocity, ti me-of-arrival differences (TOADs), and receiver positions. The magnitude of additional errors caused by geometric simplification was also assessed. Th e receiver position uncertainty had the largest impact on the precision of source location. A supplementary vertical linear array consisting of three receivers gave information on the vertical bearing and distance to the soun d sources. The TOAD data from an additional receiver as well as from surfac e reflections were used td form an overdetermined location system. This sys tem rendered positions within two standard deviations of the estimated erro rs from the original 3D array. (C) 2001 Acoustical Society of America.