High Frequency Forward Acoustic Volume Scattering and Its Relation to Oceanic Fine Structure.

• Main Authors: Holliday, D V, McCoy, J J, Beran, M J, Bratkovich, A W, Reader, W T
• Other Authors: TRACOR APPLIED SCIENCES INC SAN DIEGO CA
• Format: Text
• Language: English
• Published: 1987
• Subjects: Acoustics; *ACOUSTIC SCATTERING; *FORWARD SCATTERING; PROPAGATION; SPATIAL DISTRIBUTION; VOLUME; STOCHASTIC PROCESSES; DISSIPATION; TURBULENCE; SCALE; LENGTH; ACOUSTIC SIGNALS; OCEANS; UNDERWATER ACOUSTICS; ACOUSTIC FIELDS; INTERNAL WAVES; OPEN WATER; UNDERWATER SOUND SIGNALS; ARCTIC OCEAN; LPN-TRACOR-03-4-023; Arctic; Arctic Ocean
• Online Access: http://www.dtic.mil/docs/citations/ADA178221; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA178221

The long term objectives of this research are to provide a tool for observing oceanic events on a length scale smaller than those associated with internal waves and to provide improved predictive capabilities for direct path propagation fluctuations in the 20 to 70 KHz regime, where small scale events can dominate forward acoustic scattering. Scattering of an acoustic signal by the dynamic processes and the heterogeneous chemical and physical distribution of properties that exist in the open ocean have received considerable attention in the last decade. Our understanding of the effects of stochastic volume scatter mechanisms on a propagating acoustic field, both at the level of the second-order statistics (signal coherence measures, spread functions) and at the level of fourth-order statistics (signal intensity fluctuations and correlations) is reasonably complete. A comparably detailed description of the structure and mechanisms of physical oceanography at intermediate-to-fine scales is not yet well developed. This report represents a part of an effort to develop theory on which to base the development of new techniques to be used in developing a better understanding of the intermediate and fine scale physical processes. These are the processes that exist between the spatial scales of internal waves and the dissipative range of turbulent ocean structure.