Accession Number : ADA183486

Title :   Passive Ranging with the SNAP Model: A Performance Study,

Corporate Author : SACLANT ASW RESEARCH CENTRE LA SPEZIA (ITALY)

Personal Author(s) : Sullivan,E J ; Rameau,K

PDF Url : ADA183486

Report Date : Jul 1987

Pagination or Media Count : 16

Abstract : A passive ranging technique which used SNAP, the SACLANT Centre's normal-mode model, is studied. An examination is made of the sensitivity of the technique to errors in the assumed sound velocity profile and tilting of a 16 lambda vertical receiving array. Also, the effect of both white and coloured noise in investigated. Results indicate that for the scenario considered (summer profile in the Mediterranean with a water depth of 130 m and source ranges of 10 and 25 km), the method can be quite robust to sound velocity profile errors on the order of several m/s and array tilts on the order of 1.5 deg. Solutions were obtained with input signal-to-noise ratios as low as -13dB. Keywords: Array tilt, Bottom properties, Coloured noise, Depth, Gaussian noise, Inverse problem, Maximum likelihood, Passive ranging, Propagation, Sensitivity, Signal-to-noise ratio, SNAP(SACLANTCEN Normal mode Acoustic Propagation), Sound velocity profile, White noise.

Descriptors :   *ACOUSTIC VELOCITY, *SOUND TRANSMISSION, *RANGE FINDING, ACOUSTIC VELOCITY, BOTTOM, DEPTH, ERRORS, GAUSSIAN NOISE, INPUT, INVERSION, MAXIMUM LIKELIHOOD ESTIMATION, MODELS, NORMALITY, PASSIVE SYSTEMS, PROFILES, RANGE FINDING, SIGNAL TO NOISE RATIO, SOUND TRANSMISSION, WATER, WHITE NOISE

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE