数字预失真基本原理

17710071ThePrincipleofDigitalPre-distortionMaJin(SchoolofTelecommunicationsEngineering,XidianUniversity,Xi′an710071,China)AbstractThispapermakesamathematicalanalysisoftheHPA'sdistortioncharacteristicandintroducestheprincipleofdigitalpre-distortion.Italsosummarizessomecommontechniquesforlinearizingpre-distortionwithemphasisontheLUTmathematicalmodel'smodelingmethod.KeywordsPA;linearization;pre-distortion;LUTACPRACPR1[1]1AM-AMAM-AMAM1234/MHz870.03871.26872.49873.72750kHz,Low47.80750kHz,Up45.561.98MHz,Low50.65ACPR/dB1.98MHz,Up48.389CH750kHz,Low60.55750kHz,Up63.231.98MHz,Low66.70ACPR/dB1.98MHz,Up67.179CH2005-12-21...554433221xaxaxaxaxay++++=.2AM-PMAM-AM20069204ITAge/Sep.15,200618tymωcos=AM-AM......5cos3coscos531+++=tttymmmωβωβωβmωAM-PM135(coscos3cos5......)cos(1cos2)...2mmmcmytttttβωβωβωφωω=+++×⎡⎤+++⎢⎥⎣⎦34MESFET1DACDACPMCInterSilAlteraTelasic2DSPDAC3AM-AMAM-PM1AM-PMAM-AM355dB1()()Kkkkytbzt==∑k=1,2,3,…,Kbk2VolterraVolterra121()()()kkkikKiythTztTdTdTdT==−∑∏∫∫LLT1[,,]kKTTT=L()kh⋅kVolterra3A.Pages-Zamora,M.A.Lagunas,T.JimenezLUTLook-UpTable1/2006915191FIRPMCTI2InterSilAlteraAM-PMAM-AM1InterSil[2]2interSilinterSilDelayDelayITAge/Sep.15,2006202PMCPMCPMC3AlteraAlteraFIRInterSil12FFT[3]13aHaSanAbdulkaderFulladaptiveneuralpredistortionforsatellitenonlinearhighpoweramplifiersNNSqrt()Log2()ScaleOffsetAddressModeSelectSQ(n)SI(n)N/200691521NNNNb2PMCDSPDSPAlteraPMCXilinxCDMAWCDMAPMCCDMAACPR+CDMAWCDMA1,.[M].:,1988.2,.3GISL5239[J].,2005,(10):88903.[M].:,2005.2DQPSKI4MATLABdspdspFPGA/CPLD1,,,.DSP[M].:,2003.2,,.——MATLAB[M].:,2001.3,,,.(4)[M].:,1999.4,.(2)[M].:,2001.10008336675003331670-16710008336675003331670-167