Accession Number : ADD015866

Title :   Multiplatform Sonar System and Method for Underwater Surveillance.

Descriptive Note : Patent, Filed 28 Sep 92, patented 27 Jul 93,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Gaer, Marvin C

Report Date : 27 Jul 1993

Pagination or Media Count : 21

Abstract : A system and method of indirect underwater acoustic ocean surveillance is disclosed requiring at least two sonar platforms, usually ships, traveling some distance apart. At least one of the platforms transmits sonar pulses, portions of which are scattered off the ocean floor to at least one companion sonar receiver platform. The receiver platform is provided with means to analyze the received scattered sonic pulses to determine if a submerged object such as a submarine is obstructing a portion of the pulse, thus casting an acoustic shadow. With accurate positioning information supplied by a navigation information system such as the NAVSTAR GLOBAL POSITIONING SYSTEM (GPS), and by combining pulse measurements over several positions the system will be able to locate, identify, and track the obstructing object by analyzing these acoustic shadows or silhouettes. Geometric silhouette reconstruction techniques and other mathematical techniques may be employed to construct an image of the submerged object.

Descriptors :   *GLOBAL POSITIONING SYSTEM, *OCEAN SURVEILLANCE, *SONAR, *UNDERWATER ACOUSTICS, *PATENTS, BLOCKING, IMAGES, INFORMATION SYSTEMS, MEASUREMENT, NAVIGATION, PLATFORMS, PULSES, RECEIVERS, SHADOWS, SHIPS, SILHOUETTES, SONAR PULSES, SONAR RECEIVERS, SUBMARINES, SURVEILLANCE, TRACKS, OCEAN BOTTOM, ACOUSTIC TRACKING, ACOUSTIC SCATTERING, ACOUSTIC IMAGES

Subject Categories : Acoustic Detection and Detectors
      Navigation and Guidance

Distribution Statement : APPROVED FOR PUBLIC RELEASE