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针对猎雷声呐对水雷目标探测仿真问题,提出一种基于运动学信息与水下声场传播耦合分析的探测成像仿真方法。利用 Bellhop3D 声场分析方法对水下声信道信号冲击响应进行计算,结合信号复分析方法得到信号传播信道参数以构建声散射模型,以运动耦合方式综合分析声呐搭载平台位置、姿态及速度等因素对回波信号的影响,通过综合考虑上述因素来模拟目标回波信号,从而利用较为真实的等效回波信号进行图像重构。 以高频前视声呐为例,对声呐探测沉底水雷目标情况进行了仿真,结果表明,该方法能够得到高频声呐对沉底水雷目标的探测图像,与实际情况具有一致性,可为进一步构建反水雷相关模拟仿真训练系统提供参考。 相似文献
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针对水雷目标探测识别困难这一现实问题,分析了水雷及其声呐图像的主要特点,介绍了基于统计特征、形态学、最大熵、分形和聚类等传统水雷识别方法和基于深度学习技术的水雷目标检测算法,以期为后续算法研发提供技术参考。 相似文献
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猎雷是各海军强国重点发展方向,猎雷作战中首要的就是探测识别水雷。从传播损失、混响、 目标强度以及海流、潮汐等多个方面分析了海洋环境对猎雷声呐探测识别的影响,并从猎雷作战角度提出了有关参数设置、作战方式、数据处理等对策建议,可为部队探测识别水雷等目标提供有效参考。 相似文献
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田雪冰 《数字海洋与水下攻防》2019,2(3):51-53
探猎雷装备作为海军反水雷部队的主要装备,其探测应用研究对提高建制式反水雷装备的作战效能具有重要意义。从作战部队探猎雷实战使用流程出发,结合探猎雷装备应用现状,提出了声呐探测目标的概率分类方法,建立了探测概率分类方法模型,对实际应用需解决的问题进行了探析。对开展海区水雷目标数量评估、目标的识别比对以及声呐探测航次优化等装备作战运用有一定的启发和促进作用。 相似文献
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为了在更大深度范围海区有效打击水面目标并提高目标毁伤概率,采用水雷垂直上浮的方式攻击目标。 在水雷上浮攻击过程中,上浮引信动作时机、上浮攻击距离和上浮误差角度会对目标毁伤概率造成很大影响。 准确掌握这类上浮水雷战术特点并正确分析目标毁伤概率影响因素,对摸清水雷性能底数、评估水雷的目标毁伤概率具有重要意义。 通过建立上浮水雷垂直上浮攻击目标模型和目标毁伤概率计算模型,分析上浮引信动作时机、上浮攻击距离和误差角度等主要影响因素对目标毁伤概率的影响。 相似文献
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水雷既是弱小国家进行沿海防御、抑制强敌海上进攻的常规威慑力量,又是海上军事强国封锁对方港口、出海口和海峡,进行登陆作战的有效武器。随着水雷技术的发展,世界各国特别是技术发达国家开发研制的新型高智能、高技术水雷,在不久的将来必将成为水雷家族的朵朵奇葩。在未来的海上战争中布置这些新水雷,就会撒下天罗地网,使海上舰艇“寸步难行”。水雷素有“黑色杀手”之称,让我们来看一看未来可能装备海军部队的新型“黑色杀手”的真面目。神经网络水雷这种新型水雷采用芯片作神经网络器件,使水雷能够识别所有破坏半径以内的舰艇,… 相似文献
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随着战场信息化、智能化技术的空前发展,反水雷作战也越来越向着多平台协同作战方向发展,作为反水雷作战神经中枢的指挥控制系统作用越来越明显.其中任务规划是反水雷作战指挥控制的重要环节,建立战术任务规划系统的目标就是要减轻岸基指挥中心以及反水雷母舰工作人员的工作负荷,提高多个平台协同反水雷作战的整体效能.通过分析反水雷任务规... 相似文献
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Active sonar detection in shallow water using the Page test 总被引:1,自引:0,他引:1
The use of active sonar in shallow water results in received echoes that may be considerably spread in time compared to the resolution of the transmitted waveform. The duration and structure of the spreading and the time of occurrence of the received echo are unknown without accurate knowledge of the environment and a priori information on the location and reflection properties of the target. A sequential detector based on the Page test is proposed for the detection of time-spread active sonar echoes. The detector also provides estimates of the starting and stopping times of the received echo. This signal segmentation is crucial to allow further processing such as more accurate range and bearing localization, depth localization, or classification. The detector is designed to exploit the time spreading of the received echo and is tuned as a function of range to the expected signal-to-noise ratio (SNR) as determined by the transmitted signal power, transmission loss, approximate target strength, and the estimated noise background level. The theoretical false alarm and detection performance of the proposed detector, the standard Page test, and the conventional thresholded matched filter detector are compared as a function of range, echo duration, SNR, and the mismatch between the actual and assumed SNR. The proposed detector and the standard Page test are seen to perform better than the conventional thresholded matched filter detector as soon as the received echo is minimally spread in time. The use of the proposed detector and the standard Page test in active sonar is illustrated with reverberation data containing target-like echoes from geological features, where it was seen that the proposed detector was able to suppress reverberation generated false alarms that were detected by the standard Page test 相似文献
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在高斯白噪声背景下,匹配滤波器作为线性调频信号的最优检测器,在水声信号处理中被广泛应用。 当发射信号为线性调频信号时,由水下目标径向速度引起的多普勒频移会造成回波和样本之间失配, 使匹配滤波器的检测性能下降,增加了目标速度估计的难度。 利用分数阶傅里叶变换对于线性调频信号的聚焦特性,提出了应用分数阶傅里叶变换的水下运动目标线性调频回波检测算法,完成对目标速度的估计, 推导目标运动速度与分数阶傅里叶变换阶数之间的关系,并对测量结果进行误差分析。 仿真测试表明,该算法可有效地估计混响背景下的目标径向速度,且具有良好的估计性能。 相似文献
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Increasing the optical range of target detection and recognition continues to be an area of great interest in the ocean environment. Light attenuation limits radiative and information transfer for image formation in water. In this paper, the authors briefly review current methods of imaging and then describe a variation of the spatial interferometric technique that relies upon projected spatial gratings with subsequent detection against a coherent return signal for the purpose of noise reduction and image enhancement. A model is developed that simulates the projected structured illumination through turbid water to a target and its return to a detector. The model shows an unstructured backscatter superimposed upon a structured return signal. The model has been extended to predict what a camera would actually see, so that various noise-reduction schemes can be modeled. Finally, some water-tank tests are presented, validating original hypothesis and model predictions. The method is advantageous in not requiring temporal synchronization between reference and signal beams and may use a continuous illumination source. Spatial coherency of the beam allows for the detection of the direct return, while scattered light appears as a noncoherent noise term. 相似文献
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An active sonar is described that adaptively changes its location and configuration in response to the echoes it observes in order to locate an object, position it at a known location, and identify it using features extracted from the echoes. The sonar consists of a center transmitter flanked by two receivers that can rotate and is positioned at the end of a robot arm that has five degree-of-freedom mobility. The sonar operates in air using Polaroid transducers that are resonant at 60 kHz with a nominal wavelength equal to 6 mm. The emitted pulse has a short duration with a useful bandwidth extending from 20 to 130 kHz. Using binaural information, the transmitter rotates to position an echo-producing object on its axis to maximize the acoustic intensity incident on the nearest echo-producing feature. The receivers rotate to maximize the echo amplitude and bandwidth. These optimizations are useful for differentiating objects. The system recognizes a collection of ball bearings, machine washers, and rubber O-rings of different sizes ranging from 0.45 to 2.54 cm, some differing by less than 1 mm in diameter. Learning is accomplished by extracting vectors of 32 echo envelope values acquired during a scan in elevation and forming a data base. Recognition is accomplished by comparing a single observed echo vector with the data base to find the least squared error match. A bent-wire paper clip illustrates the recognition of an asymmetric pose-dependent object 相似文献
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《Oceanic Engineering, IEEE Journal of》2009,34(3):269-284
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R. F. Coombs 《新西兰海洋与淡水研究杂志》2013,47(3):479-488
A system to record digitised echo information from echo sounders has been developed as part of a project to improve methods of estimating the abundance of fish stocks around New Zealand. The depth of echoes appearing at the echo‐sounder receiver is determined, followed by a sequence of samples of the echo envelope defining its shape. All data are digitised and recorded on a seven‐track digital magnetic tape recorder. The system is designed to preserve as much information about the echoes as possible. In contrast to other published systems designed to either “count” or “integrate” fish echoes, this system allows free choice of methods of analysis. 相似文献
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The 2000 hydroacoustic survey of Lake Matano, Sulawesi is used to illustrate the mechanism of formation of an artificial, but acoustically-observed density layer in the midst of the water column. Such a spurious signal resembling the true acoustic target can be formed under certain combinations of the lake morphology and the echosounder settings by way of recording the residual echo from the previous ping during the subsequent ping-recording interval. The. generic physical mechanism of the phenomenon is described and the necessary conditions for its formation stated. The echosounder settings sufficient to prevent the interference during the field surveys are suggested, and their application illustrated with an example. The phenomenon described is explained by the physics of sound propagation and hence, the algorithms here developed apply to other water bodies and hydroacoustic equipment. 相似文献