共查询到18条相似文献,搜索用时 70 毫秒
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侧扫声纳和多波束测深系统在海洋调查中的综合应用 总被引:12,自引:2,他引:12
介绍了利用多波束进行全覆盖水深测量和利用侧扫声纳进行海底、水体目标的探测技术。综合利用多波束水深数据和侧扫声纳声图,可有效增强不同观测数据的互补性和提高工程质量。 相似文献
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针对利用侧扫声纳检测海底管道时因其检测声影图像模糊而导致管道悬空高度检测误差过大的问题,提出了侧扫声纳声波掠射角优化设计的思路及方法。阐述了利用侧扫声纳对海底管道进行检测的工作原理,并利用海底管道和海底底质反向散射强度的计算公式探讨了声波在海底的反向散射强度、侧扫声纳声影图像的质量以及声波掠射角的取值这三者之间的关系对海底管道悬空高度h计算精度的影响,从理论上确定声波掠射角最佳取值范围的存在。通过工程实例的现场检测与比对试验,获得了在本试验所处海域环境中利用侧扫声纳检测海底管道时声波掠射角的最佳取值范围,对于类似的海底管道检测工程具有一定的指导意义。 相似文献
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介绍了多波束测深系统和侧扫声纳系统的工作原理,通过实例说明了多波束测深系统和侧扫声纳系统在海底目标探测的工作流程,总结出两种探测系统在探测海底目标上的优缺点,说明了多种探测手段的综合应用是海底目标探测技术的发展方向。 相似文献
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从侧扫声纳各类数据的特点出发,通过构建声纳图像的地理编码模型,提出侧扫声纳图像地理编码方法,将声纳回波数据与定位数据一一对应。实验数据结果表明:该方法是合理可行的,不仅较好地处理了定位数据,消除了拖鱼轨迹线上的折点和扇形裂缝,而且可实现海底回波点的地理定位。 相似文献
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多波束与侧扫声纳海底目标探测的比较分析 总被引:2,自引:0,他引:2
侧扫声纳是目前常用的海底目标(如沉船、水雷、管线等)探测工具,在测深领域,多波束以全覆盖和高效率证明了它的优越性。由于多波束具有很高的分辨率,目前在工程上已经开始应用多波束进行海底目标物的探测。对多波束和侧扫声纳进行了比较分析,并着重探讨了影响多波束分辨率的各种因素。结果表明:多波束的最大优点在于定位精度高,但其适用范围不如侧扫声纳广泛,尤其受到水深和波束角的限制,多波束和侧扫声纳在探测海底目标时具有很好的互补性,同时应用可以提高目标解译的准确性。 相似文献
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This paper is a summary of a study of the effect of receiver position errors on the target localization accuracy of a multistatic sonar. The multistatic active system under examination consists of one or more transmitters and receivers, and the target is localized in the horizontal plane by means of echoes from the transmissions. Two-dimensional propagation of sound, with a constant sound speed, is assumed throughout. A simple analytic approach, implemented and illustrated numerically, is derived for calculating the sensitivity to receiver position error over a specified area. For many of the examples considered, there are considerable regions where target localization errors can be unacceptably large even for highly accurate receiver positions 相似文献
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针对侧扫声呐图像斑点噪声强、背景海底散射干扰严重,海底目标轮廓自动提取困难的问题,提出了一种基于K-means聚类与数学形态学相结合的海底目标轮廓自动提取算法。为克服噪声干扰,该算法首先利用中值滤波去除侧扫声呐图像中的强斑点噪声;然后采用K-means聚类算法对侧扫声呐灰度图像进行分割,并二值化,除去大部分海底背景噪声,初步提取出目标;接着利用数学形态学运算去除提取结果中的孤立噪点,并填充目标内部孔洞,得到连续化、圆滑的目标边缘;最后对处理后的侧扫声呐图像进行边缘检测,提取出目标轮廓。实验结果表明:该算法思想简单易行,具有很强的克服背景噪声的能力,自动提取的目标轮廓连续性较好,结果准确可靠。目前,在侧扫声呐图像目标轮廓提取过程中,主要采用人工方式,自动性较差,效率较低。本文算法可以实现目标轮廓的自动提取,提高效率,具有较强的实用价值。 相似文献
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《Oceanic Engineering, IEEE Journal of》2006,31(2):345-355
Predicting sonar detection performance is important for the development of sonar systems. The classical sonar equation cannot accurately predict sonar detection performance because it does not incorporate the effect of ocean environmental and source position uncertainty. We propose an analytical receiver operating characteristic (ROC) expression that characterizes the performance of the optimal Bayesian detector in the presence of ocean environmental and source position uncertainty. The approach is based on a statistical model of the environment and a physical model of acoustic propagation, which translates ocean environmental and source position uncertainty to signal wavefront uncertainty. The analytical ROC expression developed in this paper is verified for source position uncertainty due to source motion using both simulated data and real data collected during the Shallow Water Evaluation Cell Experiment (SWellEx-96). The results showed that the primary effect of source position uncertainty on optimal sonar detection performance is captured by the rank that corresponds to the significant eigenvalues of the signal matrix, an ensemble of replica signal wavefronts (normalized acoustic pressure vector) at the receiving array. The results also showed that the proposed ROC expression provides a realistic detection performance prediction for the Bayesian detector for source position uncertainty using real data. The proposed approach to sonar detection performance prediction is much simpler and faster than those using conventional Monte Carlo approaches. 相似文献
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Chunhua Yuan Azimi-Sadjadi M.R. Wilbur J. Dobeck G.J. 《Oceanic Engineering, IEEE Journal of》2000,25(1):192-205
In this paper, new pre- and post-processing schemes are developed to process shallow-water sonar data to improve the accuracy of target detection. A multichannel subband adaptive filtering is applied to preprocess the data in order to isolate the potential target returns from the acoustic backscattered signals and improve the signal-to-reverberation ratio. This is done by estimating the time delays associated with the reflections in different subbands. The preprocessed results are then beamformed to generate an image for each ping of the sonar. The testing results on both the simulated and real data revealed the efficiency of this scheme in time-delay estimation and its capability in removing most of the competing reverberations and noise. To improve detection rate while significantly minimizing the incident of false detections, a high-order correlation (HOC) method for postprocessing the beamformed images is then developed. This method determines the consistency in occurrence of the target returns in several consecutive pings. The application of the HOC process to the real beamformed sonar data showed the ability of this method for removing the clutter and at the same time boosting the target returns in several consecutive pings. The algorithm is simple, fast, and easy to implement 相似文献