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1、西南交通大學(xué)碩士學(xué)位論文基于周期無碰撞區(qū)跳頻序列的自適應(yīng)跳頻系統(tǒng)研究姓名:黃建平申請學(xué)位級別:碩士專業(yè):通信與信息系統(tǒng)指導(dǎo)教師:汪曉寧20090501西南交通大學(xué)碩士研究生學(xué)位論文第1I頁-I●-_●__●●_-__l_IIII-●_●ll_●lI_●lI-●lI-Il_I--I--I------I●Abs仃actBandcongestionproblemistheseriousprobleminthemodemciviliancommunications.Inthefrequency-hoppingcommunication,itsolvestheover-crow
2、dingproblemthattherealizationofmulti-usersharedfrequencyband.However,withnetworkcapacityincreasing,near-fareffectismoreandmoreserious.Inordertomeetnetworkperformancerequirements,itmustdealwiththeissueofmultipleaccessinterferenceinthefrequency—hoppingcommunication.Itisaself-interferences
3、ystemforFrequency-hoppingcommunicationsystemandinterferencebetweentheusersismoreserious.ffithappensonecollisionfor500jumps,thebiterrorprobability(BER)is10。.Itaffectsthequalityofcommunicationandevendisruptsthecommunicationforalargeamountofinformationlossing.hlthefrequency-hoppingcommunic
4、ations,inordertoovercomethemultipleaccessinterference(MAI),therehasbeenanumberofways.Onewayistoresearchanddesignpracticalhoppingcodewithahammingcross-correlationaslowaspossible.Otherwayistoimprovethesystembytechnologyofeliminateorreduceinterference,whichincludesAdaptiveFrequencyHopping(
5、AFH),CorrelatedHoppingEnhancedSpreadSpectrum(CHESS)andSOon.Thisthesiscombinesofthesetwowaystoimprovetheperformanceofanti.MAI.Firstofall,aNo—Hit.Zone0,,rrtz)hoppingcodewithalowcross.correlationischoosedthatonlyOCCULTSthefi'equencycollisionataparticulardisplacementofcycleandwillnotcollisi
6、onsinotherdisplacementofcycle.Then,accordingtothecharacteristicsofNo-Hit—Zone(卜mZ)hoppingcode,weproposetheNo.Hit-Zonehoppingcommunicationsystemdependsontheadaptivefi'equencyhoppingthinking.AnewadaptivefrequencyhoppingcommunicationsystemusingforNHZhoppingcodeWasstudied.Thepurposeistodoth
7、ebesttoreducethemultipleaccessinterferenceofsystem.西南交通大學(xué)碩士研究生學(xué)位論文第1II頁Inthisthesis,theauthorbuildstheadaptivefrequencyhoppingcommun-icationsystemsimulationplatformwithSIMULINKt001.Intheuser-definedmodulesoftheadaptivefrequencyhoppingcommunicationsystemsimulationplatform,Matlab