Localization of Acoustic Transients in Shallow Water Environments

• Main Author: Nicholson, Charles L.
• Other Authors: NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
• Format: Text
• Language: English
• Published: 1992
• Subjects: Acoustic Detection and Detectors; *ACOUSTIC SIGNALS; *UNDERWATER ACOUSTICS; *ACOUSTIC DETECTORS; *UNDERWATER TARGETS; ALGORITHMS; COMPUTERIZED SIMULATION; SCENARIOS; TRANSIENTS; TRANSFER FUNCTIONS; MODELS; NAVY; HYDROPHONES; BAYS; CROSS CORRELATION; ANTISUBMARINE WARFARE; TIME DOMAIN; SURVEILLANCE; ACOUSTIC VELOCITY; SUBMARINE DETECTION; BARENTS SEA; OCEANS; ACOUSTICS; GRIDS; THESES; SHALLOW WATER; RESPONSE; RECEIVERS; PARABOLAS; RECIPROCITY; Barents Sea
• Online Access: http://www.dtic.mil/docs/citations/ADA260615; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA260615

Determination an of an underwater target's position using passive acoustic sensors is of considerable use for the Navy, both for anti-submarine warfare (ASW) and underwater surveillance. This thesis proposes and develops localization algorithms capable of passively determining the location of a transient source given some broad constraints. In particular, this thesis investigates the effect of the source signal uncertainty on localizer performance. The localization process consists of two parts. First, a time domain propagation modeling code determines the impulse response of the environment from all possible source locations to a single hydrophone. This program predicts the signal as it would appear at the receiver from a grid of possible source locations. Second, source localization results from finding the maximum correlation between the positionally dependent, numerically modeled signals and the actual received signal. The position of the maximum cross correlation reveals an estimate of source position. Using model to model correlation, this technique successfully localized acoustic sources in both Monterey Bay and Barents Sea scenarios.