Use of integrated instrumentation to detect and classify targets in shallow water

• Published in: The Journal of the Acoustical Society of America 2016-10, Vol.140 (4), p.3350-3350
• Main Authors: Cotter, Emma D., Murphy, Paul, Joslin, James, Brunton, Steven, Stewart, Andrew, Polagye, Brian L.
• Format: Article
• Language: English
• Subjects: Environmental Monitoring, Adaptable Monitoring Package; TIDAL AND WAVE POWER
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4970704

The detection and classification of targets in shallow water environments (e.g., depth < 20 m) is of increasing interest, both in security applications and more general environmental studies. Here, we report the ability of a cabled integrated instrumentation system to detect and classify targets in a shallow (15 m deep), narrow (150 m wide) channel influenced by moderate tidal currents (peak currents < 2 m/s). The instrumentation system incorporates a passive acoustic array, multibeam sonar, acoustic camera, stereo-optical camera, and acoustic Doppler current profiler. The system effectiveness is benchmarked using autonomous “cooperative” targets (e.g., drifters with known position and acoustic characteristics), divers, and opportunistic observations of fish and marine mammals. By fusing data streams from multiple sensors, detection and classification rates are improved, particularly for smaller targets. Approaches to data management (data rates exceed 80 MB/s), real-time classification, and de-noising of acoustic imagery are also discussed.