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Accession Number ADA571737
Title APL - North Pacific Acoustic Laboratory.
Publication Date Sep 2011
Media Count 19p
Personal Author J. A. Mercer R. Andrew
Abstract The ultimate limitations to the performance of long-range sonar are due to ocean sound speed perturbations and the characteristics of the ambient acoustic noise field. Scattering and diffraction resulting from internal waves and other ocean processes limit the temporal and spatial coherence of the received signal, while the ambient noise field is in direct competition with the received signal. Research conducted in the North Pacific Acoustic Laboratory (NPAL) program at the Applied Physics Laboratory (APL-UW) is directed toward a complete understanding of the basic physics of low-frequency, long-range, deep water, broadband acoustic propagation, the effects of ocean variability on signal coherence, and the fundamental limits to signal processing at long-range that are imposed by ocean processes. The long-term goal of NPAL is to optimize advanced signal processing techniques, including matched-field processing and adaptive array processing methods, based upon knowledge about the multi-dimensional character of the propagation and noise fields and their impact on longrange ocean acoustic signal transmissions.
Keywords Acoustic fields
Acoustic signals
Acoustic velocity
Adaptive systems
Ambient noise
Deep water
Internal waves
Signal processing
Sound transmission
Spatial distribution
Underwater acoustics

Source Agency Non Paid ADAS
NTIS Subject Category 63A - Acoustic Detection
46A - Acoustics
47C - Physical & Chemical Oceanography
Corporate Author Washington Univ., Seattle. Applied Physics Lab.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1316
Contract Number N00014-08-1-0843 N00014-08-1-0200

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