Abstract: The present invention is a system that mathematically simulates acoustic waves that are reflected off an ocean floor from a SONAR transducer mounted on a ship, submarine, or other water navigable craft. By varying the number of mathematical equations, the form of the equations, and the parameters of the equations, many different conditions may be simulated in the laboratory before testing and implementing a SONAR system at sea. The system can simulate either a spatial hydrophone SONAR system or a temporal hydrophone SONAR system for all ship speeds (i.e. all velocity components). The novel equations used in the system are based on the physics of correlation SONAR, and are applied in real time simulation environments to provide for accurate SONAR simulation of a ship's velocity.

Abstract: A sonar system comprises a transmitter adapted to provide pulse sequences, wherein each of the pulse sequences includes pulses that reflect off an object, a receiver adapted to receive the reflected pulses, and a processor. The processor is configured to transmit a first pulse sequence via the transmitter to obtain a first distance to the object in a first distance range and to transmit a second pulse sequence via the transmitter to obtain a second distance to the object in a second distance range. The processor is configured to transmit the second pulse sequence in response to being unable to obtain the first distance to the object in the first distance range.

Abstract: In accordance with the illustrative embodiment, a diagnostic method for use with multi-element transducers includes determining an acoustic center of a transducer and determining an offset of the determined acoustic center from a theoretical acoustic center of the transducer. In some embodiments, the method also quantifies the impact that the offset has on performance of a transducer array. In some embodiments, the offset is used to correct signal processing calculations that rely on assumptions about the acoustic center of each transducer in the transducer array. A diagnostic system for use with multi-element transducers includes a projector, wherein the projector generates a sound; and a mechanical fixture, wherein the fixture aligns the projector with the transducing elements in the transducer so that in combination, the projector selectively ensonifies each of the transducing elements in the transducer.

Abstract: The present invention is a system that mathematically simulates acoustic waves that are reflected off an ocean floor from a SONAR transducer mounted on a ship, submarine, or other water navigable craft. By varying the number of mathematical equations, the form of the equations, and the parameters of the equations, many different conditions may be simulated in the laboratory before testing and implementing a SONAR system at sea. The system can simulate either a spatial hydrophone SONAR system or a temporal hydrophone SONAR system for all ship speeds (i.e. all velocity components). The novel equations used in the system are based on the physics of correlation SONAR, and are applied in real time simulation environments to provide for accurate SONAR simulation of a ship's velocity.

Abstract: An extendible linear sonar array for an Autonomous Underwater Vehicle (AUV) comprises a linear hydrophone array fixed in the nose of the AUV and two hydrophone array segments mounted at the leading edge of stabilization fins extendible from and retractable into the AUV. The stabilization fins are pivoted to move between extended and retracted positions where, in the extended position, the movable arrays together with the fixed nose array form a linear sonar array with extended width. In the retracted position, the stabilization fins with the hydrophone arrays pivot and fold back into stow channels in the AUV body. The stabilization fins may include movable control surfaces to control the attitude of the AUV, or the stabilization fins can be rotated when in the extended position to provide attitude control.