简介：Codedisseminationisanimportantbuildingblockofwirelessreprogramming.Wenoticethatcurrentcodedisseminationprotocolsfailstoconsiderpageselectionandenergybalancing.Inthispaper,wepresentanintegratedmutualselectionbasedcodedisseminationprotocol(MSD).ThekeyideaofMSDismutualselectioncomprisingsenderselectionandpageselection.Byexploitinglinkqualityinformationinmutualselection,MSDenhancesthepropagation.Further,MSDtakesenergylevelinformationinthesenderselection,thusavoidinglowpowernodes'over-consumption.WesimulateMSDbysettingsofMica-Zmotes.SimulationresultsshowthatMSDcanreducethecompletiontimeandaveragetransmission,andhelplowpowernodesavoidunnecessarytransmissionandenergyconsumption.

简介：Thisarticleisfocusedonanalyzingthekeytechnologiesofnewmaliciouscodeandcorrespondingdefensivemeasuresinthelarge-scalecommunicationnetworks.Basedondescriptionoftheconceptsanddevelopmentofthemaliciouscode,thearticleintroducestheanti-analysistechnology,splittingandinsertingtechnology,hidingtechnology,polymorphvirustechnology,andautoproductiontechnologyofthemaliciouscodetrendswithintelligence,diversityandintegration.Followingthat,itsummarizesthesecurityvulnerabilitiesofcommunicationnetworksfromfourrelatedlayersaspects,accordingtothemechanismsofmaliciouscodeinthecommunicationnetworks.Finally,itproposesrapidresponsedispositionofmaliciouscodeattacksfromfourcorrelatedsteps:buildingupthenetworknodemonitoringsystem,suspiciouscodefeatureautomationanalysisandextraction,rapidactivemaliciouscoderesponsetechniqueforunknownmaliciouscode,andmaliciouscodeattackimmunitytechnique.Asaresult,itactivelydefensesagainsttheunknownmaliciouscodeattacksandenhancesthesecurityperformanceofcommunicationnetworks.

简介：Thisarticleproposesatime/frequencysynchronizationalgorithminthemultipleinputmultipleoutput(MIMO)systems,inwhichtheperfectcompletegeneralizedcomplementaryorthogonallooselysynchronouscodegroupsareusedasthesynchronizationsequence.Thesynchronizationalgorithmisdividedintofourstages:1)synchronizationintimedomainbysignalautocorrelation;2)synchronizationinfrequencydomainbyfastFouriertransform(FFT);3)multipathdissociationusingcoherentdetectionandfinetimesynchronization;4)finefrequencyoffsetestimationbyphaserotation.Aspertheperfectcompletegeneralizedcomplementaryorthogonallooselysynchronouscodegroups,thecross-correlationandout-of-phaseauto-correlationforanyrelativeshiftbetweenanytwocodesisalwayszero.Thisidealpropertymakesthetime/frequencysynchronizationalgorithmsimpleandefficient.Thesimulationresultsshowthateveninthemultipathfastfadingchannelwithlowsignalnoiseratio(SNR),theMIMOsystemcangetsynchronizedbothinthetimedomainandfrequencydomainwithhighstabilityandreliability.

简介：为了压制边带，multiband引起直角的频率部门multiplexing(MB-OFDM)的干扰基于认知收音机系统，边带信号的一个数学表达式被导出。基于这表情，在播送符号之中的限制，帮助压制干扰，被获得。与限制结合了，块涡轮代码调整计划的一种类型被建议。在调整计划，边带干扰快速被稀释。与另外的技术相比，在这个计划，干扰抑制更容易并且足够地被实现。同时，小点错误率(BER)表演能被改进。理论分析和模拟结果证明MB-OFDM-based认知收音机系统受不了瑞利褪色是高度适用的。