Accession Number : ADA290219

Title :   A Tactical Application of Coastal Acoustic Tomography.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Franken, Jeroen

PDF Url : ADA290219

Report Date : DEC 1994

Pagination or Media Count : 66

Abstract : The objective of this study is to investigate the utility of acoustic tomography for performance assessment of a generic low frequency active sonar system. The performance of the sonar is simulated using tomography-derived sound speed data versus a range independent ocean model. The ocean environment used in the simulation is 159 tomographic snapshots of the Barents Sea Polar Front, taken every 5 minutes in August 1992. The modeled sonar system consists of a 1000 Hz source with a source level of 205.5 dB and a towed horizontal array of hydrophones. The system is derived from unclassified parameters of ATAS (Active Towed Array Sonar), built by Thomson Sintra ASM and British Aerospace SEMA, and the experimental ALF sonar, designed by FEL-TNO (the Netherlands) and built by Thomson Sintra ASM. The tomographic images over a range of 26 km provide a realistic ocean in which system performance is assessed. This study used a broadband, coupled normal mode, propagation model and assumed a noise-limited condition. The probability of detection calculated as a function of time for 13 hours is compared with that estimated using a range- and time-independent assumption. The utility of coastal acoustic tomography for tactical applications is discussed. (AN)

Descriptors :   *TOMOGRAPHY, *SONAR, COMPUTERIZED SIMULATION, EXPERIMENTAL DATA, COASTAL REGIONS, TOWED ARRAYS, ACOUSTIC DETECTION, THESES, ACOUSTIC IMAGES, BROADBAND, ACOUSTIC SIGNALS, NOISE REDUCTION, HYDROPHONES, TACTICAL WARFARE, UNDERWATER ACOUSTICS, BARENTS SEA, OCEAN MODELS, OCEAN ENVIRONMENTS, LOW FREQUENCY, ANTISUBMARINE WARFARE, BATHYTHERMOGRAPH DATA, SOUND RANGING.

Subject Categories : Acoustic Detection and Detectors
      Physical and Dynamic Oceanography
      Undersea and Antisubmarine Warfare

Distribution Statement : APPROVED FOR PUBLIC RELEASE