Browsing by Subject "Active sonar"
Now showing items 1-20 of 29
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A shallow water system for maximizing echo to reverberation ratio
(NATO. SACLANTCEN, 1993/08)A method for increasing incident energy on mid-depth targets while at the same range reducing boundary reverberation for shallow water ducts has been devised. The basis of the approach is couched in range dependant normal ... -
Active detection enhancement in coastal areas
(NURC, 2006/08)The processing chain used for active detection analysis in association with measures of performance that allow real time performance monitoring is presented. Real life examples demonstrating environmental volatility ... -
Active signal detection in shallow water using the Page test
(NATO. SACLANTCEN, 1996/11)The use of active sonar in shallow water results in received echoes that may be considerably spread in time compared to the transmitted wave form. The duration and structure of the spreading and the time of occurrence of ... -
Adaptive autonomous underwater vehicles for littoral surveillance: the GLINT10 field trial results
(NURC, 2012/05)Autonomous underwater vehicles (AUVs) have gained more interest in recent years for military as well as civilian applications. One potential application of AUVs is for the purpose of undersea surveillance. As research into ... -
Adaptive filter of seabed clutter onboard the AUVs of an active multistatic sonar network
(CMRE, 2019/05)This work aims at reducing the false alarm rate of a multistatic active sonar working in coastal, shallow waters. The sonar system is implemented through a heterogeneous manned-unmanned network including autonomous underwater ... -
Adaptive normalization of active sonar data
(NURC, 2006/08)In active sonar detection the background interference is reduced through normalization prior to applying a detection threshold. From the two mainstream normalization algorithms, i.e. the sliding window and the split window, ... -
Benchmark evaluation of multistatic trackers
(NURC, 2006/08)This paper provides an overview of the Special Session on Multistatic Sonar and Radar Tracking at FUSION 2006. This includes background on the Multistatic Tracking Working Group, a brief description of the datasets and ... -
Bottom time spread and bistatic scattering by rough basalt
(NATO. SACLANTCEN, 1993/08)Scattering from oceanic basalt affects low-frequency active sonar systems in at least two important ways: (1) Significant time, angle and frequency spreading reduces target echo levels when systems over-resolve the spread; ... -
Channel sensitive processor: real data processing
(NATO. SACLANTCEN, 1998/02)The CSP is applied to data collected during the DUSS97 sea trial. A one-way geometry is used and the transmitted signal propagation time is known a priori. As predicted by analytical and simulation studies, the CSP detector ... -
Channel-adapted source for shallow water
(NATO. SACLANTCEN, 1993/08)In shallow water areas the utilization of active sonar is complicated by the fact that in these environments the performance of active systems is degraded by source signal interaction with channel boundaries. These boundary ... -
Channel-sensitive processor: development and detection performance evaluation
(NATO. SACLANTCEN, 1997/03)A Channel Sensitive Processor (CSP) which improves upon the detection performance of the traditional matched filter is developed. This method compensates for the performance degradation of the matched filter due to dense ... -
Continuous recording of active sonar data
(NATO. SACLANTCEN, 1972/05) -
Critical angle and seabed scattering issues for active-sonar performance predictions in shallow water
(NATO. SACLANTCEN, 1997)Active sonar performance predictions (0.75 to 3 kHz) are examined in summer shallow-water environments to quantify the impact of variable seabed and watermass properties on detection. Scattering is computed with an ... -
Delay-Doppler resolution performance of large time-bandwidth product linear FM signals in a multi- path ocean environment
(NATO. SACLANTCEN, 1989/04)Active sonar systems that transmit large time-bandwidth (TW)-product linear frequency modulated (LFM) waveforms and receive echoes from targets of unknow~r~an ge and speed can suffer considerable correlation losses that ... -
Distributed information fusion in multistatic sensor networks for underwater surveillance
(CMRE, 2019/06)Surveillance in antisubmarine warfare has traditionally been carried out by means of submarines or frigates with towed arrays. These techniques are manpower intensive. Alternative approaches have recently been suggested ... -
Distributed information fusion in multistatic sensor networks for underwater surveillance
(CMRE, 2017/11)Surveillance in antisubmarine warfare has traditionally been carried out by means of submarines or frigates with towed arrays. These techniques are manpower intensive. Alternative approaches have recently been suggested ... -
High resolution feature extraction from reverberation data
(NATO. SACLANTCEN, 1997)A new method of signal approximatzon is presented which has the capability to model complex active returns due to reverberation. The method explored herein is data adaptive in the sense that high resolution processing is ... -
Low frequency active sonar: a NATO Conference held by SACLANTCEN on 24-28 May 1993 - collection of unclassified papers - volume 1 of 2
(NATO. SACLANTCEN, 1993/08)A conference on Low Frequency Active Sonar was held at SACLANTCEN from 24th to 28th May 1993. The conference was attended by over 100 delegates from NATO countries, and the topics presented ranged from environmental aspects, ... -
Low frequency active sonar: a NATO Conference held by SACLANTCEN on 24-28 May 1993 - collection of unclassified papers - volume 2 of 2
(NATO. SACLANTCEN, 1993/08)A conference on Low Frequency Active Sonar was held at SACLANTCEN from 24th to 28th May 1993. The conference was attended by over 100 delegates from NATO countries, and the topics presented ranged from environmental aspects, ... -
Model-aided data adaptive suppression of reverberation
(NATO. SACLANTCEN, 1993/08)We propose a processing methodology which is based on the piece-wise modeling, adaptive estimation, and removal of reverberation components. An important feature of this approach is that backscatter models and information ...