混沌弱信號檢測技術.pdf

1、哈爾濱工程大學碩士學位論文混沌弱信號檢測技術姓名：王麗霞申請學位級別：碩士專業(yè)：水聲工程指導教師：張攬月20110319混沌弱信號柃測技術ABSTRACTChaostheoryisanonlinearbranchofscience，whichisappliedtodifferentengineeringfieldChaostheoryismostappliedinthesignaldetectionwhichiscurrentlyone

2、ofthefrontiersubjectsresearchedThisthesisresearcheschaostheoryfordetectingweaksignalThetraditionalsignaldetectiontheoryprocessestimedomainsignalbasedonstatisticaltheoryandthedetectionperformanceishardtoimproveThethesisan

3、alyzesthecharacteristicsofchaostheoryandestablishestwosignaldetectionmodels：thechaoticdetectionweakperiodicsignalmodelandthetransientsignaldetectionmodel，whichareappliedtounderwatertargetdetectionFirstlythispaperstudiest

4、hechaostheoryandthebasiccharacteristicsofchaos，andresearchesthetwocharacteristicsofchaosquantity：LyapunovexponentandfractaldimensionSecondlythethesisestablishesthechaoticdetectionweakperiodicsignalmodelThemodelmakesuseof

5、dynamicsbehaviorcharacteristicsofDuffingsystem，whichisinchaoscriticalstateWeaddweakperiodicsignaltosuchasystem，changingthesystematicphasespacestateTheexperimentprovesthatthismodelcalldetectweakperiodicsignalsoflowinputSN

6、RLastlythethesisconstructsthetransientsignaldetectionmodelbasedonchaostheoryUnderwatersignalisquitecomplexsignalthatisnottotallyrandomsignal，butithascertainchaoscharacteristicsAccordingtothechaoticpropertyofunderwaterbac

7、kgroundnoise，thismodeladoptedsingle—stepforecastmethodofradialbasisfunctionneuralnetworkwhichisusedtodetectunderwatertransientsignalTheexperimentisprovedthemodelfordetectingairdropmodelhittingwaterofthesignals，anditverif