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Incoherent processing of synthetic aperture sonar. [PDF]

, 2004
The technique of synthetic aperture imaging is well applied in radar to produce images with high along-track resolution. However, when applied in sonar imaging, maintaining phase coherence across the length of the synthetic aperture had proven to be the greatest challenge due to the relatively much slower speed of sound waves and the instability ...
Foo, Kae Yeet
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Azimuthal ambiguities in synthetic aperture sonar and synthetic aperture radar imagery

IEEE Journal of Oceanic Engineering, 1992
It is shown that azimuthal ambiguities are not eliminated by the nulls of a sonar (or radar) beam pattern and have a definite influence on image quality. In synthetic aperture systems that are strongly limited in spatial sampling, particularly in ocean borne synthetic aperture sonar (SAS) and spaceborne synthetic aperture radar (SAR), azimuthal ...
K.D. Rolt, H. Schmidt
exaly   +2 more sources

A CTFM synthetic aperture sonar

, 1989
This thesis describes the theory and operation of a seafloor imaging Synthetic Aperture Sonar (SAS), based on broadband Continuous Tone Frequency Modulation (CTFM). Narrowband synthetic aperture techniques are reviewed, and some of the limitations of using such techniques in sonar applications are described.
Hayes, Michael P.
openaire   +3 more sources

Synthetic aperture sonar

The Journal of the Acoustical Society of America, 1973
This letter describes the principle and the fundamental results of experiments of a synthetic aperture sonar which enables us to resolve objects both in angle and range more sharply than the conventional ultrasonic imaging system. The basic idea of this technique is to introduce pulsed waveforms to ultrasonic holography and its operations consist of ...
Takuso Sato, Mitsuhiro Ueda, Sadanao Fukuda   +2 more
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Synthetic aperture active sonar imaging

[Proceedings] ICASSP-92: 1992 IEEE International Conference on Acoustics, Speech, and Signal Processing, 1992
The main problems involved in synthetic aperture sonar imaging are medium instability, slow mapping rate, and platform motion. Proposed solutions to these problems are reviewed, and a new technique for synthetic aperture sonar imaging is presented which allows a fast mapping rate and improved motion compensation.
Brett L. Douglas, Hua Lee
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Sequential Synthetic Aperture Sonar System-A Prototype of a Synthetic Aperture Sonar System

IEEE Transactions on Sonics and Ultrasonics, 1977
A prototype of a synthetic aperture sonar system is presented which displays computationally reconstructed images on a CRT. The image information is obtained sequentially by the scanning in twodimensions of a transmitter-receiver unit which produces and detects pulsed ultrasonic waves.
T. Sato, O. Ikeda
openaire   +1 more source

Synthetic aperture sonar on AUV

Oceans 2003. Celebrating the Past ... Teaming Toward the Future (IEEE Cat. No.03CH37492), 2003
Synthetic aperture sonars (SAS) and autonomous underwater vehicle (AUV) are two of the most exciting technologies under development by the underwater research and development community. Integration of these technologies promises to produce underwater acoustic imaging systems of tremendous capability and versatility.
J.E. Fernandez, J.T. Christoff, D.A. Cook   +2 more
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An introduction to synthetic aperture sonar

Proceedings of the Tenth IEEE Workshop on Statistical Signal and Array Processing (Cat. No.00TH8496), 2002
DTI has demonstrated that synthetic aperture sonar (SAS) can provide orders of magnitude improvement in cross-range resolution when compared to conventional sonar beamforming. Like synthetic aperture radar (SAR), SAS processing requires coherence over multiple measurements, but has long been impractical due to the nature of the ocean environment.
D. Marx, M. Nelson, E. Chang, W. Gillespie, A. Putney, K. Warman   +5 more
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Simulation of synthetic aperture sonars

The Journal of the Acoustical Society of America, 1994
Coastal Systems Station is developing a high-fidelity simulation of low- and high-frequency imaging synthetic aperture sonars in coastal regions. This simulation includes a coherent bottom and surface reverberation model that treats reverberation as a Gaussian random process; 3-D coherent beam patterns for the projector and receiver arrays; a 3-D ...
G. S. Sammelmann, J. T. Christoff, J. D. Lathrop   +2 more
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Bionic synthetic aperture sonar

The Journal of the Acoustical Society of America, 1997
Dolphinlike sonar signals are used to obtain synthetic aperture images of complicated, three-dimensional (3-D) objects from transmitter–receiver positions that are above the plane of effective target rotation. This geometry allows 3-D information to be incorporated into a SAS image.
Richard A. Altes, Patrick W. B. Moore
openaire   +1 more source