基于Matlab的OFDM仿真实现及性能分析

MatlabOFDM王玲,逯贵祯,肖怀宝(,,100024):正交频分复用(OFDM)是第四代移动通信的关键技术,以其为基础的地面数字电视传输技术也已经发展得比较成熟它具有较高的频谱效率和抵抗多径的能力,这使其在无线通信中的应用也具有相当的优势,已成为目前解决高速数据传输的主流技术之一本文介绍了OFDM的基本原理和主要结构,并以DVB)T标准的2K模式作为参考,使用MATLAB语言实现了OFDM系计算机仿真仿真最后给出在不同的信道条件下,保护间隔对OFDM系统星座图误码率的影响,得出了较理想的结论:正交频分复用;DVB-T;保护间隔;星座图:TN911:A:1673-4793(2010)02-0045-05PerformanceAnalysisandSimulationRealizationofOFDMSystemBasedonMATLABWANGLing,LUGui2zhen,XIAOHuai2bao(CommunicationUniversityofChina,Beijing100024,China)Abstract:Orthogonalfrequencydivisionmultiplexing(OFDM)isakeytechniqueofthefourthgenerationmobilecommunication.TheterrestrialdigitaltelevisiontransmissiontechnologybasedontheOFDMtech2niquehasbedevelopedmoremature.Ithashighefficiencyandresiststhemulti-pathfading.Thusitsapplicationinwirelesscommunicationhasconsiderableadvantageandhasoneofthecurrentmainstreamtechnologiestosolvethehigh-speeddatatransmission.ThebasicprincipleandmainstructureofOFDMareintroducedinthepaper.Basedonthe2kmodelofDVB-Tstandardasreference,computersimula2tionofOFDMsystemisrealizedbytheMATLAB.Finallyinthedifferentchannels,theinfluenceoftheguardintervalontheconstellationanderrorrateoftheOFDMsystemisalsogiven.Theidealconclusionisdrawn.Keywords:OFDM;DVB-T;Guardinterval;simulation;MATLAB1OFDM,OFDM4G,CD2MA,OFDM(ADSL)ETSI(DAB)(DVB)(HDTV)(WLAN)OFDMMIMOLDPC,,OFDM:2009-11-26:(1974-),(),,17OFDM,OFDM,,OFDMAWGNRayleigh,2OFDMOFDM(MCM),MCMN,N1/N,N,MCMN()OFDM,,OFDM(S/P),,1,,2,1OFDM2OFDM,#Rb,M,Rs=Rb/log2M;#)))B=Rs,Bs=2B,=Rb/Bs=(1/2)log2M;#OFDM(N))))S/PRs/N,;#Bm=(N+1)(Rs/N);#=Rb/Bm=[N/(N+1)]#log2MOFDMDSP(FFT)(IFFT),3()/,IDFTIFFT/,,/OFDM3OFDM462:MatlabOFDM,/,,/DFTFFT,OFDM,/3OFDMOFDMDAB,DVBADSL,OFDM,DVB-SQPSK,DVB-TQAMDVB-T2K,OFDM18MHZ2KOFDM8MHZT7/64us4,MATLABMMMM,MMATLAB,MATLAB,Min2put,M,,,C++4MATLABOFDM18MHz2KOFDM2KK1705Kmin0Kmax1704Tu224us1/Tn4464HzKminKmax(K-1)/Tu7161Hz44.1SNR68OFDM,SNR,SNR=2,6,12,678:,SNR,,9,SNR,,SNR,ISI54QAM412GG=1/4,$=56LsSNR6dB4717multime,,multime=0Ls,7multime=20Ls50Ls,60Ls101112,,,482:MatlabOFDM1260LsISI,,,,,,,DVB-TCOFDM,,14%,,30%,5OFDM,OFDMMATLABOFDM,,,,OFDM[1],.MATLAB6[M].,2002.[2],.[M].,1999.[3],.[M].,2003.[4]1DVB-T1,2005,11(6)1[5],1OFDM1,2009,8(1)1(:)(58)[3].CMTS[D].,2004.[4].HFCDOCSISMAC[D].,2006.[5],.VxWorksCMTS[J].,2003,(5).[6],.VxWorksCMTS[J].,2004,(12).[7]DavidFellows,DougJones1DOCSISTMCableModemTechnology[J]1IEEECommunicationMagazine,2001,9(3).(:)49