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题名	南中国海北部内波环境下匹配场定位研究
作者	吴开明
学位类别	博士
答辩日期	2009-05-27
授予单位	中国科学院声学研究所
授予地点	声学研究所
关键词	动态海洋环境监测 动态海洋环境建模 水声传播模拟 匹配场定位
其他题名	Matched Field Position Study in the internal wave Environment in the North of South China Sea
学位专业	声学
中文摘要	大陆架附近海域大幅度内波的动态存在是对该海域水声技术的一个严峻挑战，它造成测量声场的严重起伏；匹配场定位是建立在对海洋声传播准确模拟基础上的目标定位方法，它将实测水声信号与模拟声场信号相匹配来确定目标的深度和距离；但是面对内波等大幅度的海洋动态，水声传播模拟所需的动态海洋环境参数通常难以实时准确预报。 本论文根据ASIAEX2001南中国海北部近两个月水声学-海洋学综合实验，通过对比研习适于海洋信道环境较快变化的水声传播程序RAM-PE，采用对温度链观测数据经过“温-盐度拟合”结合“平流-冻结海洋模型”来数值模拟“动态海洋环境”，算出这种海洋动态下的声场，并进一步研究这种持续海洋动态下声场的匹配场自相关时间对应的变化，研究表明，模拟的海洋动态能够实时模拟出海洋声场的动态变化。 本论文还研习了多种窄带和宽带匹配场处理器，这些匹配器对单目标拉距、多目标拉距、对运动目标的定位，以及这些匹配器对于噪声背景的容忍能力等问题，研究表明，采用测量场和模拟场宽带相干积分的匹配方法定位效果更好。在此基础上，结合数值模拟的声场，准确模拟了实验中跨大陆架方向水声信道中的匹配场定位。然后选择水平海底，拷贝场和测量场一个用内波声速切面，一个用平均声速场来考察内波动态下的环境失配对匹配场定位的影响，继续就实验中350m处深水温度链的实测内波，对比选择内波较弱和较强时的海洋环境，以及大幅度内波刚进入传播信道、在信道中央以及快出信道时三种变化剧烈的海洋环境，设定不同声源位置、不同阵元组合、以及不同频率配置的情形，对匹配场定位能力作了研究，本研究展示了上述各种情形下大幅度内波动态对于匹配场定位影响的丰富结果，结果表明，即使在大幅度内波动态情况下，对于不同的目标位置，采用适当深度的阵元组合和合适的处理频段，可以进行较远距离准确的匹配场定位。 除了上述用观测数据通过数值模拟来构建匹配场定位所需的动态海洋声学环境参数，根据国际海洋监测现有成果及未来规划，本论文还提出可以结合现有丰富的海洋监测数据库和各种动态海洋数理模型，来构建并实时预测可用于匹配场处理的动态海洋环境参数。这方面还有很多工作亟待展开。 本论文研究2007年入选为 “中国科学院知识创新工程青年人才领域前沿项目”(项目号：0754021111)。
英文摘要	The dynamic large internal wave near the continental shelf is a big challenge to the acoustic technology because it causes the sound field a serious fluctuation. Matched-field position has just founded on the correct simulation of the oceanic sound propagation and it detects the range and depth of a target by correlating the measured and the simulated sound signal. But it’s commonly very hard to predict the dynamic oceanic acoustic environment parameter on time in the dynamic ocean when the internal waves are active. This dissertation studied the sound propagation program RAM-PE which suits the changed environment with other two programs. Then, using the 2-month-long T-string data in the ASIAEX2001 ocean acoustics-oceanography experiment in the north of the South China Sea, adopting a fitting relation of the temperature and salinity and a flow-frozen-ocean model, we simulated the dynamic ocean environment numerically. And then the sound field was calculated in the dynamic ocean. Also the continuous changed matched-field autocorrelation time of the sound field was calculated corresponding to the ocean dynamic. This dissertation also studied some narrow and wide band matched-field processors and their applying in single-target, multi-targets and moving target, also their tolerance with the noise background increasing. The study result is that the wide-band correlation matched-field processor can get a better positioning effect. Applying the numerically simulated sound field, an exact simulated position was done in cross-shelf ocean environment in ASIAEX2001. Then selecting a flat bottom, and using several internal wave SVPs to calculate the copied field, mean SVP for the source-emitting field to study the influency on the MFP that dynamic oceanic envinment has caused. with the 350m T-string data, we simulated the matched-field position with different source positions, different array cells combination and different frequency band in a strong and a weak internal wave background, also in three strong internal wave background that a soliton has just gone into, is about to go out, and in the middle of transfer channel. These simulations indicated that in the dynamic ocean, the MFP can detect the target position correctly in a far distance when the depth of array cells has been properly combined and the a suitable frequency band was applied. Including the numerical simulating that can construct the ocean dynamic environment, according to the current international oceanography observation and their future plan, we can also integrate the existed ocean observation database and some excellence mathematics-physics oceanic dynamic model, so that the dynamic oceanic acoustic environment parameter can be forecast to apply in MFP. There are also many research in this field that should be kept on going. The content of the disertation was constituted as a Youth Pioneer Projects of Chinese Academy of Science in Knowledge Innovation Works in 2007(Project No.: 0754021111).
语种	中文
公开日期	2011-05-07
页码	126
内容类型	学位论文
源URL	[http://159.226.59.140/handle/311008/294]
专题	声学研究所_声学所博硕士学位论文_1981-2009博硕士学位论文
推荐引用方式 GB/T 7714	吴开明. 南中国海北部内波环境下匹配场定位研究[D]. 声学研究所. 中国科学院声学研究所. 2009.

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