微弱信号检测技术的研究

编号微弱信号检测技术的研究ResearchonWeakSignalDetectionTechnology学生姓名专业学号学院年月日I摘要在自然现象和规律的科学研究和工程实践中,经常会遇到需要检测毫微伏量级微弱信号的问题,比如测定地震的波形和波速、材料分析时测量荧光光强、卫星信号的接收、红外探测以及物电信号测量等,这些问题都归结为噪声中微弱信号的检测。在物理、化学、生物医学、遥感和材料学等领域有广泛应用。微弱信号检测技术是采用电子学、信息论、计算机和物理学方法,分析噪声产生的原因和规律,研究被测信号的特点和相关性,检测被噪声淹没的微弱有用信号。微弱信号检测的宗旨是研究如何从强噪声中提取有用信号,任务是研究微弱信号检测的理论、探索新方法和新技术,从而将其应用于各个学科领域当中。本文对弱信号的定义和弱信号的应用范围进行了概述,综述了微弱信号检测理论研究和实际应用领域的发展情况,重点比较了目前在微弱信号检测技术中应用的方法:相关检测、锁相放大器微弱信号检测、取样积分法、基于小波分析的微弱信号检测、基于混沌振子的微弱信号检测,最后总结了各个方法的特点。关键字：微弱信号检测噪声锁相放大器IIABSTRACTInthenaturalphenomenonandlawofscientificresearchandengineeringpractice,oftenbeexpectedtotestbaekhomicrovoltsmiddleweightweaksignalissues,suchasdeterminationofearthquakewaveandwavevelocity,materialanalysiswhenmeasuringfluorescentlightintensity,satellitesignals,infrareddetectionandsignalmeasurementofthings,theseproblemsboildowntoaweaksignalinthenoiseofthetest.Inthephysical,chemical,biologicalmedicine,remotesensingandmaterialscienceandotherfieldshaveawidelyused.Weaksignaldetectiontechnologyistheelectronics,informationtheory,computerandphysicsmethod,analyzesthereasonsofthenoiseandtostudythelawsofthemeasuredsignalcharacteristicsandcorrelation,detectionwassubmergedinthefaintnoiseusefulsignal.Theaimoftheweaksignaldetectionisstudyinghowstrongnoisefromtheextractusefulsignal,thetaskistostudythetheoryofweaksignaldetection,explorenewmethodsandnewtechnology,anditsapplicationinthefieldofeachsubject.Thedefinitionoftheweaksignalandtheapplicationrangeoftheweaksignalwerereviewedinthispaper,theweaksignaldetectionintheoreticalresearchandpracticalapplicationofthefielddevelopmentsituation,thekeyisthecurrentweaksignaldetectiontechnologyintheapplicationmethod:relateddetection,lock-inamplifierweaksignaldetection,samplingintegralmethod,basedonthewaveletanalysis,weaksignaldetectionbasedonchaoticoscillatorweaksignaldetection,finallysummarizedthecharacteristicsofeachmethod.Keywords：Weaksignal,detection,andnoise,lock-inamplifierIII目录摘要..............................................................................................................................................IABSTRACT....................................................................................................................................II第1章绪论....................................................................................................................................11.1引言..................................................................................................................................11.2微弱信号的定义..............................................................................................................11.3微弱信号的应用范围及当前的研究背景......................................................................11.4微弱信号检测的原理......................................................................................................2第2章相关检测法........................................................................................................................42.1自相关检测......................................................................................................................42.1.1自相关检测的举例.................................................................................................52.2互相关检测......................................................................................................................62.2.1互相关检测的特点...............................................................................................7第3章锁相放大器微弱信号检测...............................................................................................83.1锁相放大器介绍及应用..................................................................................................83.2锁相放大器的原理..........................................................................................................93.3锁相放大器特点............................................................................................................113.4系统中相关器的分析....................................................................................................113.5锁相放大器的局限性....................................................................................................12第4章取样积分法......................................................................................................................134.1取样积分器的工作原理................................................................................................134.2取样积分器的信噪比改善系数....................................................................................154.3取样积分器的工作方式................................................................................................164.3.1定点式取样积分器.............................................................................................164.3.2扫描式积分取样器...........................................................................................16第5章基于小波分析的微弱信号检测.......................................................................................185.1小波变换的介绍及发展................................................................................................185.2小波变换