Research On The Method Of Acoustic Detection Of Underwater Hydrothermal

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.