【作者】 刘文海；

【导师】 杨德森；

【作者基本信息】 哈尔滨工程大学 ， 水声工程， 2010， 博士

【摘要】 随着鱼雷技术的迅速发展,如何有效地防御鱼雷的进攻成为潜艇防御与水下武器对抗的重要研究课题。鱼雷空投和潜射过程中,产生了击水声、盖板声、点火声等瞬态信号。与其他信号相比,这些瞬态信号具有独特的特征,对于及时发现鱼雷和快速进行鱼雷报警有着重要意义。首先对鱼雷空投和潜射过程产生瞬态信号的机理进行了研究,并在此基础上,对信号进行了仿真和试验数据的处理。对空投入水过程进行了研究,得出其对应的各个阶段信号特点,仿真了入水冲击声、寂静段和脉动声信号。对潜射鱼雷所涉及的瞬态信号进行了研究,在对鱼雷潜射过程分析基础上,提取了相应的盖板声、点火声等瞬态信息。经过对仿真信号和三个潜射鱼雷试验数据样本的处理,对潜射鱼雷瞬态信号,尤其是盖板声、点火声信号的特点进行了研究。其次,对于空投和潜射鱼雷瞬态信号分析方法进行了研究、对比和应用。对常规信号处理方法的特点进行了分析,仿真验证了时频测不准原理以及复杂包络形式对时频分析的影响。对EMD分解理论进行了阐述,研究了EMD分解在不同信噪比条件下的性能,结果表明以EMD分解为基础的模态分解方法是一种具有稳健性、适合于不同信噪比场合应用的有效手段。1(1/2)谱是目前应用较为广泛的高阶统计量分析手段,它具有独特的谐波检测能力,在分析谐波成分存在时有很好的处理效果。针对鱼雷空投和潜射过程中的击水声、盖板声、启动声等瞬态信号,给出了各自适用的瞬态信号处理方法。试验数据处理结果表明,盖板声信号由多次响应及其谐波成分构成,适合采用时频分析、EMD分解或者两者结合进行研究;击水声信号的起始尖峰是较强的脉冲信号,能量比较集中,采用短时能量检测器有利于稳健的检测,其后续脉动信号可在EMD分解的模态信息下予以分析。点火声属于一个复杂的信号,它包括发动机噪声和螺旋桨的噪声。根据鱼雷启动过程中的系列瞬态信号,设计了一种基于统计量的联合瞬态信号检测器,理论和试验数据处理结果表明该处理器对于较低信噪比下鱼雷启动信号的检测性能有着显著的提升。最后,在水下瞬态信号短时能量检测基础上,对实测瞬态信号利用分离子阵实现了对敲击声源的定位。设计了一种鱼雷盖板声和点火信号的数据联合定位方法,可实现对鱼雷发射瞬态信号的定位。对比结果表明数据信息的联合可以提高样本有效长度,改善系统定位精度。针对鱼雷线谱特性分析问题,设计了一套线谱净化、归类措施。研究了二阶自适应跟踪滤波器,提高了对轨迹的滤波跟踪性能。设计了基于Hough变换的轨迹信息增强方法,仿真了对于微弱运动目标轨迹增强能力,对被动定位轨迹跟踪效果进行了改善和性能提高。上述诸方面措施的综合应用,将为提升潜艇对鱼雷的防护能力提供更好的手段和技术支持。本文对于鱼雷启动阶段瞬态特征进行了分析,并探讨了相关瞬态信号处理方法,研究成果将为潜艇对鱼雷的早期预警、探测和定位跟踪服务。更多还原

【Abstract】 With the rapid development of torpedo technology,how to effectively prevent the torpedo attack and fight as an important research topic on submarines and AW (acoustic warfare).The feature of torpedo related transient signal is the most useful information for torpedo warning sonar.The torpedo related signals, includes some transient signals attributed to the torpedo missile entry into the water,cover sound and ignition of the engine etc.These transient signals compared with other underwater targets signals has unique characteristics which have great significance for long range torpedo warning sonar to find the threats early in time.Firstly,in this dissertation,the process of mechanism analysis,transient signals simulation and experiment research for aerial and submarine-launched torpedo are researched.Aerial torpedo related physical processes are studied,corresponding to various stages of signal characteristics,and impulsive splashing noise,silent period and the pulse of shock period signals are simulated.Transient signals on submarine and torpedo have been studied.On the base of torpedo launch mechanism of the process analysis,transient information is extracted of the corresponding plate covering sound,engine igniting sound and navigation sound.Through the results of simulation and three submarine-launched torpedo experiment data samples,with the especially concerning about covering signal and ignition signal,the characteristics of the sound of submarine-launched torpedo related signals are studied.Secondly,transient signal analysis methods,related with aerial and submarine-launched torpedo,are researched and compared,with the support of mechanism researching.The characteristics of conventional signal processing methods are analyzed.To the examplify the weakness of general TFA method,the time-frequency uncertainty principle and the effect of complex envelope form are simulated on computer.Furtherly,the theory of EMD decomposition is elaborated to study the EMD decomposition performance under different SNR.The results demonstrate that the EMD approach is a robust method suitable for all kinds of SNR application occasions.The 1(1/2)spectrum is the most widely used methods of HOS,and it has a unique harmonic detection,analysis of harmonic components in the presence of a very good treatment effect.Particularly,a multiple components transient signal detector based on the statistics value,is presented in this dissertation.Through simulation and experiment data analysis,it shows that the detector improves the detection ability of the torpedo at lower SNR. For the transient signals of entry into the water,cover sound and ignition of the engine on the process of aerial and submarine-launched torpedo,their corresponding transient signal processing methods are given.For the cover sound , the repeated response and harmonic components appeared in the observation of the results of the transient signal processing,therefore cover sound is suitable for time-frequency characteristics,EMD decomposition,or combination of the two methods;the start peak of entry water signals,whose energy is more concentrated,is the very narrow peak.So the energy detector is conductive to stability detecting,and the follow-up pulsations can be analyzed in EMD decomposition to modal information;The ignition sound signals are complex signals,including the engine noise and propeller noise,so it needs more complex processing method.According to the series of transient signals during the launching of torpedo,this dissertation derives a kind of combined transient signal detector based on the statistical value.Theory analysis and experimental data testify the improvement of detection ratio at lower SNR for the torpedo launching signal’s detection.Finally,the location of very narrow pulse onboard is achieved via the 3 elements array,using the short time energy detector.A kind of synthesis method of plate covering signal and torpedo startup signal is designed,and analyzed.It shows the ability to localize the start position of torpedo launching.Through the comparison,the advantage of enlarge the sample length and improvement of precision of localization are discussed.The enhancing,purifying and clustering of line spectrum are researched to foundation the tracking of underwater high speed motion targets.A special after-processed system of 2-order adaptive tracking filter,adapted to the application of passive positioning and tracking sonar,is designed.And the enhancing of weak target trajectory is achieved via Hough transform.All these methods add up to improve the ability to the defense of torpedo for submarine.The research of this dissertation addresses to the problem of analysis of transient signal related with the torpedo startup.Corresponded signal processing methods are discussed.Result of this dissertation will apply to the application of warning,detection,positioning and tracking torpedo for the submarine in the near future.更多还原