power control wcdma

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1、PowerControlWCDMAPage2PowercontrolmethodsadoptedforvariousphysicalchannelsPowercontrolmethodsadoptedforvariousphysicalchannels"X"–canbeapplied,"–"–notappliedPhysicalchannelOpenlooppowercontrolInnerlooppowercontrolOuterlooppowerControlNopowercontrolprocess,powerisspecifiedbyu

2、pperlayers.DPDCH－XX－DPCCHXXX－PCCPCH－－－XSCCPCH－－－XPRACHX－－－AICH－－－XPICH－－－XPowerControlClassificationOpenLoopPowerControlOpenlooppowercontrolisusedtodetermineUE’sinitialuplinktransmitpowerinPRACHandNodeB’sinitialdownlinktransmitpowerinDPDCH.Itisusedtosetinitialpowerreferencev

3、aluesforpowercontrol.OuterLooppowercontrolOuterlooppowercontrolisusedtomaintainthequalityofcommunicationatthelevelofbearerservicequalityrequirement,whileusingaslowpoweraspossible.Innerlooppowercontrol(alsocalledfastclosedlooppowercontrol)InnerlooppowercontrolisusedtoadjustUE

4、’suplink/NodeB’sdownlinkDpchPowereveryoneslotinaccordancewithTPCcommands.Innerlooppowercontrolfrequencyis1500Hz.Page4Chapter2PowerControlAlgorithm2.1Openlooppowercontrol2.2Inner-looppowercontrol2.3OuterlooppowercontrolContentsPage5OpenLoopPowerControlOverviewPurposetheUEesti

5、matesthepowerlossofsignalsonthepropagationpathbymeasuringthedownlinkchannelsignals,thencalculatethetransmissionpoweroftheuplinkchannelTheopenlooppowercontrolprincipalUndertheFDDmode,fastfadingoftheuplinkchannelisunrelatedtofastfadingofthedownlinkchannel.Page6OpenLoopPowerCo

6、ntrolOverviewthedisadvantageofopenlooppowercontrolThispowercontrolmethodisrathervagueApplicationscenariosofopenlooppowercontrolIntherangeofacell,signalfadingcausedbyfastfadingisusuallymoreseriousthanthatcausedbypropagationloss.Therefore,openlooppowercontrolisappliedonlyatth

7、ebeginningofconnectionsetup,generallyinsettingtheinitialpowervalue.Page7OpenlooppowercontrolofPRACHApplicationscenarios1.CCCH:RRCConnectionRequestOpenlooppowercontrolofPRACH5.DownlinkSynchronisationUENodeBServingRNSServingRNCDCH-FPAllocateRNTISelectL1andL2parametersRRCRRCNBA

8、PNBAP3.RadioLinkSetupResponseNBAPNBAP2.RadioLinkSetupRequestRRCRRC7.CCCH:RR