Results 161 to 170 of about 1,088,237 (198)

Synthetic Aperture Sonar Primer

1997
Abstract : The goal of the Synthetic Aperture Sonar (SAS) primer is to understand the effect of the ocean water properties on the propagation of acoustic signals for frequencies and horizontal ranges that are applicable to SAS Navy systems currently being developed.
Kevin Williams, Frank Henyey
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Evaluation of a synthetic aperture sonar with a multi-aperture transducer

Proceedings of 1998 International Symposium on Underwater Technology, 2002
This paper presents a synthetic aperture sonar with a multi-aperture transducer. The pulse repetition frequency (PRF) is automatically modified so that conditions for both maximum search range and azimuth resolution are simultaneously satisfied. The PRF modification makes the ratio of two aperture lengths an integer, each of which is obtained for the ...
I. Yamaguchi, J. Kato
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The prehistory of synthetic aperture sonar

The Journal of the Acoustical Society of America, 1997
It is necessary to go back to 1958 (A.D.) and the summer of 1959. The concept of using recorded data obtained from a single moving element to provide a ‘‘memorized array’’ instead of the multiple-element physical array, was offered to ONR (Aubrey Pryce), whose reaction will be described.
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Multi-aspect synthetic aperture sonar

OCEANS 2000 MTS/IEEE Conference and Exhibition. Conference Proceedings (Cat. No.00CH37158), 2002
Multi-aspect or multi-look processing is known to improve the image quality and target detection capability of high resolution synthetic aperture sonar (SAS) imaging systems. We present in this paper a brief description on the topic and typical results obtained from sea data collected while fielding the High Frequency/Low Frequency Synthetic Aperture ...
J.E. Fernandez, J.T. Christoff
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Synthetic aperture sonar in turbulent media

The Journal of the Acoustical Society of America, 1979
A method of synthetic aperture sonar imaging that is effective even in turbulent media is proposed. Signals received at a fixed point on a scanning plane are used as reference signals, and the averaging effect is applied in the process of aperture synthesis to obtain stable images within the same scanning time as conventional methods. The principle and
Ikeda, Osamu, Sato, Takuso, Ohshima, Hajime   +2 more
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Multipath in synthetic aperture sonar

The Journal of the Acoustical Society of America, 2002
Synthetic aperture sonar is capable of producing high resolution images. As the detection range increases multipath effects can become important. In this paper we present the results of at-sea tests in the Gulf of Mexico and St. Andrew Bay with a dual-frequency (20 kHz and 180 kHz) synthetic aperture sonar.
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Method and system for synthetic aperture sonar

The Journal of the Acoustical Society of America, 2008
A method and system for synthetic aperture sonar provide improved position estimates of a receive array as in moves through a body of water.
Ian B. Kerfoot, James G. Kosalos
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Results of synthetic aperture sonar experiments

OCEANS 2000 MTS/IEEE Conference and Exhibition. Conference Proceedings (Cat. No.00CH37158), 2002
Results are presented from synthetic aperture sonar (SAS) experiments with three different test systems: one oriented toward mine detection; one toward buried UXO detection; and one toward buried cable detection. The first two systems share hydrophone arrays of 32-10-cm long elements.
M. Neudorfer, J. Kosalos, R. Bonneau
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The Potential Of Synthetic Aperture Sonar

2000
No abstracts are to be cited without prior reference to the author.This paper initially looks at the fundamental design constraints that limit the resolution capabilities of sea floor mapping using sidescan sonar. With such constraints in mind we then compare sidescan with a new emerging technology known as synthetic aperture sonar (SAS).
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A short history of synthetic aperture sonar

IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174), 1998
The fundamental theory that underpins any synthetic aperture sonar (SAS) is the same as that developed for synthetic aperture radar (SAR). However, the slow speed of propagation and higher attenuation of acoustic waves in water provides for some significant practical differences.
P.T. Gough, D.W. Hawkins
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