Luan Van Mimo-Ofdm

  • View
    16

  • Download
    5

Embed Size (px)

DESCRIPTION

Luan Van Mimo-Ofdm

Text of Luan Van Mimo-Ofdm

Document

I HC QUC GIA H NI TRNG I HC CNG NGH Nguyn Quang Vinh NGHIN CU H THNG MIMO-OFDM Ngnh:Cng ngh in t - Vin thng Chuyn ngnh: K thut in t M s:62.52.70 LUN VN THC S NGI HNG DN KHOA HC: GS.TSKH. HUNH HU TU H Ni - 2007

LI CM NTi xin by t s bit n n thy gio GS.TSKH. Hunh Hu Tu hngdn, ch bo tn tnh v dnh thi gian qu bu gip ti hon thnh lun vn ny.Ti cng by t s cm n n gia nh, c quan v bn b ng vin, h trv gip ti trong qu trnh hc tp v lm lun vn.i

MC LCLI CM N ..................................................................................................iMC LC ........................................................................................................iiDANH MC HNH .........................................................................................ivDANH MC CH VIT TT ......................................................................viM U ..........................................................................................................11. Tnh cp thit ca ti ..................................................................................2. Thc trng nghin cu MIMO-OFDM ...........................................................3. Mc tiu ca lun vn v hmng gii quyt ....................................................134CHNG 1: M HNH KNH MIMO .......................................................51.1. M hnh knh MIMO ...................................................................................1.2. Dung nng knh MIMO ...............................................................................1.2.1. Dung nng knh SISO, SIMO, MISO, MIMO .......................................1.2.2. Dung nng knh UT, IT .........................................................................1.3. M ha khng thi gian v ghp knh khng gian ......................................1.3.1. Cc k thut phn tp ............................................................................1.3.2. M ha khng gian - thi gian (STC) ...................................................1.3.3. Ghp knh khng gian (SM) ..................................................................1.3.4. So snh STC v SM ...............................................................................1.4. Mt s phmng php t hp u thu ............................................................1.4.1.T hp la chn (SC) ............................................................................1.4.2.T hp chuyn mch (SWC) ..................................................................1.4.3.T hp t s ti a (MRC) ......................................................................1.4.4.T hp khuch i ng u (EGC) ......................................................5881013131526292930303132ii

CHNG 2: H THNG MIMO-OFDM V C LNG KNHMIMO-OFDM ...........................................................................342.1. c trmng knh a mng .............................................................................2.2. H thng OFDM v nguyn l hot ng ....................................................2.3. Kt hp MIMO-OFDM ................................................................................2.4. lc lmng knh trong h thng MIMO-OFDM ..........................................2.4.1. Phng php c lng knh dng tn hiu hoa tiu (PACE) .............2.4.2.c lng knh trong h thng MIMO-OFDM ....................................343743454551CHNG 3: M PHNG ............................................................................. 553.1. Thit lp tham s m phng..........................................................................3.2. So snh cht lmng OFDM v MIMO-OFDM..............................................3.3. So snh LS v MMSE ..................................................................................3.4. nh hmng ca dch tn Doppler f ..........................................................d3.5. nh hmng ca tri tr rms ...........................................................................3.6. nh hmng ca s lmng mng truyn ........................................................3.7. nh hmng ca tri tr ti amax................................................................55565860626365KT LUN ...................................................................................................... 68TI LIU THAM KHO .............................................................................. 70PH LC A. L THUYT THNG TIN ................................................... 73PH LC B. MT S KHI NIM, NH NGHA V MA TRN ...... 78PH LC C. M NGUN CHNG TRNH M PHNG ................... 83iii

DANH MC HNHHnh 1-1.H thng MIMO c n ng-ten pht v n ng-ten thu ..........................TR5Hnh 1-2.Dung nng knh SISO, MISO, MISO ....................................................9Hnh 1-3.Dung nng knh MIMO ......................................................................... 10Hnh 1-4.Minh ha knh theo tr ring .................................................................. 11Hnh 1-5.Minh ha nh l y ..................................................................... 13Hnh 1-6.M ha STBC ......................................................................................... 16Hnh 1-7.S khi m ha Alamouti .................................................................. 19Hnh 1-8.M ha STTC ......................................................................................... 22Hnh 1-9.B m ha STTC vi trmng hp 2 ng-ten pht ................................... 23Hnh 1-10. S m lmi iu ch QPSK 4 trng thi vi 2 ng-ten ...................... 25Hnh 1-11. Cu trc D-BLAST ................................................................................. 26Hnh 1-12. Gii m D-BLAST ................................................................................. 27Hnh 1-13. Phmng php t hp la chn ................................................................. 30Hnh 1-14. Phmng php t hp chuyn mch ......................................................... 31Hnh 1-15. Phmng php t hp t s ti a .............................................................. 32Hnh 1-16. So snh cht lmng cc phmng php t hp u thu ............................. 33Hnh 1-17. T hp EGC vi s ng-ten thu khc nhau ............................................ 33Hnh 2-1.Phn b Rayleigh .................................................................................... 36Hnh 2-2.Phn b Ricean ....................................................................................... 36Hnh 2-3.Nguyn l iu ch OFDM .................................................................... 38Hnh 2-4.Dng sng ca mt k hiu OFDM ........................................................ 38Hnh 2-5.Nguyn l gii iu ch OFDM ............................................................. 39Hnh 2-6.Thm CP vo k hiu OFDM ................................................................. 40Hnh 2-7.Chn khong bo v trit tiu nhiu ISI ................................................. 41Hnh 2-8.S khi h thng thu-pht OFDM ..................................................... 42iv

Hnh 2-9.H thng MIMO-OFDM ......................................................................... 43Hnh 2-10. M hnh chn k hiu hoa tiu trong mt khung d liu OFDM ........... 46Hnh 2-11. lc lmng knh PACE 2x1D ................................................................. 49Hnh 2-12. H thng MIMO-OFDM ........................................................................ 52Hnh 2-13. Cu trc khung tn hiu MIMO-OFDM ................................................. 53Hnh 3-1.Phn b cng sut a mng theo hm e m .......................................... 56Hnh 3-2.Gin chm sao vi h thng OFDM ................................................. 57Hnh 3-3.Gin chm sao vi h thng MIMO-OFDM ..................................... 57Hnh 3-4.So snh cht lmng h thng OFDM v MIMO-OFDM ........................ 58Hnh 3-5.Gin chm sao vi mc lmng knh theo lut LS .............................. 59Hnh 3-6.Gin chm sao vi mc lmng knh theo lut MMSE ....................... 59Hnh 3-7.So snh cht lmng h thng khi mc lmng theo LS v MMSE ............ 60Hnh 3-8.Gin chm sao vi dch tn Doppler khc nhau .......................... 61Hnh 3-9.nh hmng ca dch tn Doppler ln cht lmng h thng ............... 61Hnh 3-10. Gin chm sao vi tri tr rms khc nhau ......................................... 62Hnh 3-11. nh hmng ca rms ln cht lmng h thng ......................................... 62Hnh 3-12. Gin chm sao khi s lmng mng truyn khc nhau ...................... 64Hnh 3-13. nh hmng ca s lmng a mng i vi cht lmng h thng ........... 64Hnh 3-14. Gin chm sao khi tri tr ti a thay i so vi CP ......................... 66Hnh 3-15. nh hmng ca tri tr ti a ln cht lmng h thng ........................... 66Hnh A-1. M hnh knh AWGN ............................................................................ 75v

DANH MC CC CH VIT TTAWGNAdditive White Gaussian NoiseTp m Gauss trng cng tnhBCE Blind/Semi-Blind ChannelEstimationlc lmng knh bng phmng phpmBERBit Error RateXc sut li bitBLASTBell Labs LAyered Space-TimePhn lp khng gian-thi gian dophng th nghim Bell xutCP Cyclic PrefixTin t vngD-BLAST Diagonal-BLASTBLAST phn lp choDDCEDecision-Directed ChannelEstimationlc lmng knh quyDFTDiscrete Fourier TransformBin i Fourier ri rcEGCEqual Gain CombiningT hp khuch i ng uFFTFast Fourier TransformBin i Fourier nhanhIDFTInverse Discrete Fourier Transform Bin i Fourier ri rc ngmcIFFTInverse Fast Fourier TransformBin i Fourier nhanh ngmcISI Intersymbol InterferenceNhiu xuyn k hiuLSLeast SquaredBnh phmng ti thiuMIMO Multi-Input Multi-OutputK thut x l nhiu u vo nhiuu raMLMaximum Likelihood(nh l) xc sut ging nhau cc iMMSEMinimum Mean Square ErrorTi thiu li trung bnh bnh phmngMRCMaximal Ratio CombiningT hp t s ti aOFDMOrthogonal Frequency DivisionMultiplexingGhp knh phn chia theo tn s trcgiaoPACEPilot-Aided Channel Esti