【作者】 林芳；

【导师】 郭龙祥；

【作者基本信息】 哈尔滨工程大学 ， 信号与信息处理， 2010， 硕士

【摘要】 随着人类对海洋的日益关注,海洋探查与资源的开发技术主题转化为加快以海洋油、气为主的矿产资源的探测和开发。为了提高海洋资源开发利用的效率,对海洋探测的高新技术需求越来越强烈。在海洋探测技术中,探测海底热液更是带来了重大的科学研究意义和经济价值。本文的理论和仿真部分,列举研究了气泡的频率特性、尺度分布和散射截面等声学特性,通过这些声学的基本特性,建立海底热液的相关仿真模型。运用了多种有效的回波处理方法,提高了海洋热液探测模拟系统的性能。使用动态范围归一化方法,以此来补偿和消除几何损失造成的信号平均幅度的衰减。利用简化的滤波-预测-反馈修正方法对海底测深结果进行滤波,从而提高测深精度。通过改进后置图像处理的显示技术,来增强目标回波的视觉分辨力。为了验证方法的有效性,设计了模拟探测海洋热液的试验方案,进行了水池试验研究和湖上试验研究。在水池试验中,以静态方式来探测水下模拟气幕,分析水池实验数据,了解气幕的基本特性,确立了利用回波起伏强度信息探测水下气幕的可行性。调试和改进了海底热液模拟性试验硬件系统的各种性能,在湖上试验中,测试了通过改进的走航式模拟气幕方法实时探测的性能,为在大洋中利用声学回波方法探测海底热液提供了技术支持。综合本论文研究结果表明,利用回波声图、走航探测水下热液的方法和设计具有可行性。更多还原

【Abstract】 Throughout its history,ocean exploration has witnessed the great value for human being, in particular, the subjects of marine exploration and resources exploitation have turned to the oil, gas-based mineral, etc. In order to improve the efficiency of development and utilization of marine resources, high technologies of marine detection are needed more and more. Among all the technologies, the detection of submarine hydrothermal has more significance and brings more economic value in marine exploration.Theoretically, the acoustic characteristics, such as frequency response of the bubble, size distribution and scattering cross-section are listed to build the related modeling. Furthermore, the simulation of the submarine hydrothermal, according to the theoretical model , is achieved. Some effective processing approaches, easily but adequate for engineering application, are used to improve the performance of submarine hydrothermal detection system. To compensate and eliminate the attenuation, caused by geometric loss in average magnitude, the dynamic range normalization is employed. Furthermore, an improved dynamic filter, using the thought of filter-forecast-feedback, is designed to increase the precision of seabed bathymetry. Finally, through the modified displaying technology for the post-image processing, the visual resolution of target echo is enhanced.For the test of the ability of acoustic remote detection, a scheme to miniature the marine hydrothermal detection is established.Meanwhile, pool trial and lake trial are designed and analysised. During the pool experiment, the underwater bubble cloud is detected statically. Basic acoustical characteristics of the bubble cloud are studied with acquired data. Then the feasibility of detecting underwater bubble cloud, through the fluctuation of echo intensity information, is checked. Upon the testing and the debugging of hardware, the lake trial is carried out. Thus, the performance of improved walk-propelled bubble probe method is tested. That checks out the veracity of dynamic detection. It will be a technical support of the submarine hydrothermal detection based on acoustic remote sensing in the sea.The result of this dissertation shows that the detection of submarine hydrothermal information through echo sound walk-propelled curtain probe is highly effective and very feasible.更多还原