Research/Patents/US 5909409
US 5909409

Assignee

Filed

Jan 8, 1969

Granted

Jun 1, 1999

Location

Abstract

An underwater combination of a passive and an active acoustic mechanism issed to detect and locate a surfaced or submerged object or target. The passive mechanism utilizes a pair of separated hydrophones to detect an object. The hydrophones are then followed by bandpass filters according to the frequency of interest and the outputs thereof correlated to locate the object. A positive correlation output indication initiates the active acoustic mechanism which then verifies the detection of an object by transmitting a pulse sonar. The output of a transducer responsive to the reflected pulse sonar is then analyzed to indicate whether the detected object is surfaced or submerged and whether the detected object is approaching, departing or stationary.

Source: Google Patents

35 USC §181 Secrecy Order

Imposed

Oct 28, 1981

Rescinded

Dec 1, 1997

Duration

16 years, 1 month

Technology Domains

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Back to patent indexSource: USPTO 35 USC §181 secrecy order records