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《碩士論文擴(kuò)頻通信系統(tǒng)的擴(kuò)頻序列研究》由會(huì)員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、擴(kuò)頻通信系統(tǒng)的擴(kuò)頻序列設(shè)計(jì)研究摘要首先,本文對(duì)傳統(tǒng)的m序列設(shè)計(jì)進(jìn)行了分析,發(fā)現(xiàn)了傳統(tǒng)基于GF(2)的m序列生成方法的不足,提出了應(yīng)用復(fù)制理論生成m序列的設(shè)計(jì)方法,可以在不知道生成多項(xiàng)式的前提下完整地生成m序列;同時(shí)建立了一套擴(kuò)頻序列高效計(jì)算機(jī)搜索模型及其算法,應(yīng)用該算法,通過(guò)計(jì)算機(jī)搜索并構(gòu)造挑選得到了大量的m序列優(yōu)選對(duì)及擴(kuò)頻序列聯(lián)通集。其次,本文對(duì)Walsh正交擴(kuò)頻碼作了一定研究,通過(guò)對(duì)常規(guī)生成Walsh碼的設(shè)計(jì)方法分析,提出了一種新型的Walsh函數(shù)生成及發(fā)生器設(shè)計(jì)方案。最后,文章對(duì)混沌通信系統(tǒng)的擴(kuò)頻序列進(jìn)行研究,包括Logi
2、stic-map及其改進(jìn)型映射和Kent映射混沌序列。介紹了Logistic-map模擬混沌序列的生成實(shí)現(xiàn)方法,并通過(guò)matlab將模擬混沌序列的相關(guān)性能和理論分析作了一定比較。從數(shù)學(xué)上得到了改進(jìn)型Logistic-map混沌序列的統(tǒng)計(jì)特性,并通過(guò)仿真,分析了其相關(guān)性能。同時(shí)研究了Kent映射混沌序列和Logistic-map映射混沌序列的二進(jìn)制序列性能,通過(guò)對(duì)序列的均值、自相關(guān)函數(shù)、互相關(guān)特性、相關(guān)旁瓣與互相關(guān)均方根值、互相關(guān)峰值、游程與平衡性等多方面的分析比較,說(shuō)明兩種混沌映射序列均適合于擴(kuò)頻通信系統(tǒng),而Kent混沌序列更適
3、合于保密性和抗干擾性強(qiáng)的通信場(chǎng)合。關(guān)鍵詞:m序列復(fù)制理論聯(lián)通集Walsh碼Logistic-map混沌序列Kent混沌序列擴(kuò)頻通信擴(kuò)頻通信系統(tǒng)的擴(kuò)頻序列設(shè)計(jì)研究AbstractThedesignofconventionalm-sequenceisresearchedinthepaperfirstly.Shortageofgeneratingm-sequencebasedonGF(2)isfound.Thedesignmethodofgeneratingm-sequencesappliedcopytheoryisadvanced.
4、Itgeneratesm-sequencewithoutknowingaboutcreatingpolynomial.Inthesametime,anefficientcomputersearchmodelanditsnewalgorithmarepresented.Bythewayofmakingcomputertosearchandselect,wecanmakeagreatdealm-sequencesoptimumpairsandthecorrelationcongregate.Theninthethirdpart,th
5、epaperresearchesWalshcodeacertainextent,anditbringoutanewwaytogenerateWalshfunctioncomparedwithtraditionalway.Thefourthlypartinthispaperanalyzesthespectrumsequenceinchaoticcommunicationsystemfinally.forexample,Logistic-mapanditsmodifiedchaoticsequenceandKentchaoticse
6、quence.ItintroducestherealizingwayforsimulativeLogistic-mapchaoticsequences,anditcomparesthecorrelationperformanceofsimulativechaoticsequenceswiththeoryanalyzing.Thenthispaperderivesthemathematicalexpressionofstatisticalpropertiesofchaoticsequencesgeneratedbyimproved
7、Logistic-map.Thesimulationresultsareveryclosetotheoreticalvalues.Finally,theKentbinarychaoticsequenceisinvestigatedandcomparedwiththeimprovedlogisticbinarychaoticsequenceinrespectoftheperformanceofautocorrelation,cross-correlation,runandbalance.Itispointedoutthatthis
8、twochaoticsequencesareapplicableinspreadspectrumcommunication,especially,theKentchaoticsequencemakesithighlyapplicableinsecreteanda