资源描述：
《challenges and soulutions of cognitive radio》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、HindawiPublishingCorporationEURASIPJournalonAdvancesinSignalProcessingVolume2010,ArticleID381465,15pagesdoi:10.1155/2010/381465ReviewArticleAReviewonSpectrumSensingforCognitiveRadio:ChallengesandSolutionsYonghongZeng,Ying-ChangLiang,AnhTuanHoang,andRuiZhangInsti
2、tuteforInfocommResearch,A∗STAR,Singapore138632CorrespondenceshouldbeaddressedtoYonghongZeng,yhzeng@i2r.a-star.edu.sgReceived13May2009;Accepted9October2009AcademicEditor:JinhoChoiCopyright©2010YonghongZengetal.ThisisanopenaccessarticledistributedundertheCreativeC
3、ommonsAttributionLicense,whichpermitsunrestricteduse,distribution,andreproductioninanymedium,providedtheoriginalworkisproperlycited.CognitiveradioiswidelyexpectedtobethenextBigBanginwirelesscommunications.Spectrumsensing,thatis,detectingthepresenceoftheprimaryus
4、ersinalicensedspectrum,isafundamentalproblemforcognitiveradio.Asaresult,spectrumsensinghasrebornasaveryactiveresearchareainrecentyearsdespiteitslonghistory.Inthispaper,spectrumsensingtechniquesfromtheoptimallikelihoodratiotesttoenergydetection,matchedfilteringdet
5、ection,cyclostationarydetection,eigenvalue-basedsensing,jointspace-timesensing,androbustsensingmethodsarereviewed.Cooperativespectrumsensingwithmultiplereceiversisalsodiscussed.Specialattentionispaidtosensingmethodsthatneedlittlepriorinformationonthesourcesignal
6、andthepropagationchannel.Practicalchallengessuchasnoisepoweruncertaintyarediscussedandpossiblesolutionsareprovided.Theoreticalanalysisontheteststatisticdistributionandthresholdsettingisalsoinvestigated.1.Introductionis,detectingthepresenceoftheprimaryusers.Whene
7、vertheprimaryusersbecomeactive,thesecondaryusershaveItwasshowninarecentreport[1]bytheUSAFederaltodetectthepresenceofthemwithahighprobabilityCommunicationsCommission(FCC)thattheconventionalandvacatethechannelorreducetransmitpowerwithinfixedspectrumallocationrulesh
8、averesultedinlowspectrumcertainamountoftime.Forexample,fortheupcomingIEEEusageefficiencyinalmostallcurrentlydeployedfrequency802.22standard,itisrequiredforthesecondaryu
