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题名	海洋环境不确定性对声纳性能预报的影响
作者	李凡
学位类别	博士
答辩日期	2009-05-26
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	声纳性能预报 不确定环境参数 接收机工作特性曲线 作用距离
其他题名	Effects of environmental uncertainties on sonar performance prediction
学位专业	信号与信息处理
中文摘要	声纳系统的实际性能与海洋环境密切相关。传统的声纳性能预报很少考虑环境不确定性的影响。近十几年来，海军作战范围已经从深海向浅海区域转移，浅海环境的时空变化非常大，环境参数的空间非均匀性分布和时间变化不确定性限制了传统声纳性能预报系统的预报效果。因此，海洋环境参数不确定条件下的声纳性能预报逐渐成为一个热点研究问题。 本文首先讨论声速剖面、海深、海底底质声学参数不确定性以及目标深度未知对声场分布和声纳性能预报的影响，然后在此基础上提出一种环境参数不确定情况下基于贝叶斯估计的声纳性能预报方法—最佳贝叶斯处理器，把声纳性能预报问题转化为统计学的假设检验判决问题。将环境参数和目标位置的不确定性对声纳性能预报的影响转化为接收信号矩阵的不同实现。分别利用Monte Carlo评估方法和接收机工作特性近似解析表达式，计算虚警概率和检测概率，给出接收系统工作特性曲线。利用NRL标准不确定环境模型检验比较Monte Carlo方法和近似ROC解析表达式的预报结果，并对某型号声纳进行性能预报。最后从声纳方程和优质因子角度提出一种环境参数不确定情况下的声纳作用距离预报方法。这种方法考虑不确定性因素影响，预报结果更加客观实际，更具有合理性。利用新的作用距离预报方法对某型号声纳作用距离进行预报，并对预报结果进行了试验验证。
英文摘要	Sonar performance prediction is typically associated with the realistic ocean environment. Traditional methods consider little about the effect that arises from the uncertainty of the environment parameters on the performance prediction. Recently, Navy tactical situation transfer from the deep water to the shallow water. The spatial and temporal variations in the channel parameters of the shallow water make accurate characterization of the channel difficult and cause severe performance degradation to the sonar detection prediction. A practical sonar performance prediction method that incorporates the effects of environmental uncertainty and predicts sonar detection performance more accurately, is of practical interest. Sonar performance prediction that depends on the sonar equations is only related to the uncertainty of sound field. The set of propagation channel parameters, such as the ocean bottom depth and the sound speed profile, together with the source position parameters constitute an uncertain ocean acoustic environment. Firstly, the dissertation present the effects of environmental uncertainty on sound field and demonstrate the uncertain phenomenon .Here an optimal Bayesian detector is derived based on a statistical model of environmental uncertainty. We combine physics model of acoustic propagation with the statistical modal of environmental uncertainty to relate the signal wave front with uncertain acoustic source and ocean acoustic parameters. Detection performance predictions can be performed with analytic ROC expression and numerical methods such as Monte Carlo performance evaluations. Probability of detection and probability of a false alarm can be achieved with the above two approaches. The simulated environments which come from a general mismatch benchmark environment proposed by NRL Workshop are used to compare analytical ROC expression performance predictions with Monte Carlo method prediction. The kind of realistic sonar performance is predicted by the two methods. Finally, a new approach is derived to predict the sonar detection range. The estimating approach incorporates the effects of environmental uncertainty is more accurate and reasonable. Experiment results of sonar detection range are used to test the prediction method.
语种	中文
公开日期	2011-05-07
页码	85
内容类型	学位论文
源URL	[http://159.226.59.140/handle/311008/458]
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	李凡. 海洋环境不确定性对声纳性能预报的影响[D]. 声学研究所. 中国科学院声学研究所. 2009.

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