Results 171 to 180 of about 3,360 (206)
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A PMHT algorithm for active sonar
SPIE Proceedings, 2004ABSTRACT The Probabilistic Multi-Hypothesis Tracking (PMHT) algori thm proposed by Streit and Luginbuhl in 1995 is adapted here for use in active sonar applications. PMHT is a batch technique that uses the Expectation-Maximization (EM) algorithm to obtain MAP estimates of the sequence of target states. Probabilistic Multi-Hypothesis Tracking for Active
Christian G. Hempel, Sheri L. Doran
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A Theory of Active Sonar Detection
Proceedings of the IRE, 1959The results of a theory of echo detection developed for radar are extended to sonar for the case of narrow-banid transmitted signals. The exposition specifically omits discussion of the decision problem and the statistical nature of the whole process of detection.
J. Stewart, E. Westerfield
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Design of the Active Sonar Responder
2018 2nd IEEE Advanced Information Management,Communicates,Electronic and Automation Control Conference (IMCEC), 2018The active sonar responder can provide coordinate target for the development, the test and the acceptance of the active sonar. The paper analyzes the characteristics of typical active sonar signal briefly. Then the active sonar responder is designed. The hardware design and the software design are enlarged on.
Xiaoqing Zheng +3 more
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Active sonar and the marine environment
AIP Conference Proceedings, 2004A study of the effects of active sonar transmissions on fish and marine mammals in Norwegian waters has been launched following the ordering of new frigates by the Royal Norwegian Navy (RNoN). The frigates will be equipped with active sonars operating at lower frequencies than those of the sonars currently in operation in the RNoN.
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A Brief History of Active Sonar
Aquatic Mammals, 2009As background for this special issue on strandings and mid-frequency active sonar (MFAS), this paper presents a brief history of active sonar, tracing the development of MFAS from its origins in the early 20th century through the development of current tactical MFAS.
Angela D'Amico, Richard Pittenger
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Diversity in multistatic active sonar
Oceans '99. MTS/IEEE. Riding the Crest into the 21st Century. Conference and Exhibition. Conference Proceedings (IEEE Cat. No.99CH37008), 2003A multistatic network of autonomous active transmitters and receivers, such as deployable underwater surveillance systems, often provides multiple contacts of the same target. The present paper examines the effects of receiver diversity ("spatial diversity") on a multistatic system, where three independent, spatially separated sonar receivers detect ...
L. Mozzone, S. Bongi, F. Filocca
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The Journal of the Acoustical Society of America, 2001
The decomposition of the time reversal operator (DORT) is a single frequency method of spatially isolating scatterers with a multiple-source/multiple-receiver system [C. Prada et al., J. Acoust. Soc. Am. 99, 2067–2076 (1996)]. The application of the DORT technique to a broadband sonar system is explained by showing its relationship to the sonar ...
David M. Fromm, Charles F. Gaumond
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The decomposition of the time reversal operator (DORT) is a single frequency method of spatially isolating scatterers with a multiple-source/multiple-receiver system [C. Prada et al., J. Acoust. Soc. Am. 99, 2067–2076 (1996)]. The application of the DORT technique to a broadband sonar system is explained by showing its relationship to the sonar ...
David M. Fromm, Charles F. Gaumond
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The Journal of the Acoustical Society of America, 1991
A channel adaptive active sonar is disclosed, wherein the sonar transmit waveform is adaptively selected in accordance with the measured sonar channel scattering function to reduce the response of the sonar to unwanted reverberation while preserving the response to signal returns.
P. L. Feintuch, F. A. Reed
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A channel adaptive active sonar is disclosed, wherein the sonar transmit waveform is adaptively selected in accordance with the measured sonar channel scattering function to reduce the response of the sonar to unwanted reverberation while preserving the response to signal returns.
P. L. Feintuch, F. A. Reed
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Survey of active sonar simulations
The Journal of the Acoustical Society of America, 2004In lieu of well-characterized measured data sets, time series simulations are often employed for testing active sonar systems. This paper reviews the simulation techniques and models that are being employed today and discusses some of the issues of fidelity that may arise with regard to range dependence, bistatic geometries, reverberation statistics ...
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Whales and Sonar: Environmental Exemptions for the Navy’s Mid-Frequency Active Sonar Training
2021Mid-frequency active (MFA) sonar emits pulses of sound from an underwater transmitter to help determine the size, distance, and speed of objects. The sound waves bounce off objects and reflect back to underwater acoustic receivers as an echo. MFA sonar has been used since World War II, and the Navy indicates it is the only reliable way to track ...
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