基于MATLAB实现OFDM系统的解码摘要自80年代,数字移动通信技术逐渐开始成熟,并开始应用在各式各样的，种类不同的无线通信系统，例如，数字集群电话，数字蜂窝电话，无线寻呼等，以上使用的是特高频/甚高频波段的数字移动通信。但是这两者的移动信道存在很多问题，噪声干扰，在多径传播时易造成码间串扰，选择性衰弱等。为解决这些问题，又出现了一种更好的，更高效的调制方式，就是（正交频分复用）OFDM。它是第四代移动通信技术的关键、核心技术，也被广泛应用在移动通信的领域。它不仅信道利用率比较高，而且抗衰弱能力良好。正交频分复用(OFDM)发送的信号用码元周期为T的不归零方波作为其基带码型，并由一组正交的正弦信号作为其副载波调制而成的。OFDM的信号产生与解调的过程就是IDFT/DFT的变换过程。关键字：正道频分复用，OFDM，调制方式DecodingofOFDMSystemBasedonMATLABAbstractSincethe1980s,digitalmobilecommunicationtechnologyhasgraduallymatured,andbegantobeappliedinavarietyofwirelesscommunicationsystems,suchasdigitaltrunkingtelephone,digitalcellularphone,wirelesspaging,etc.TheaboveusesdigitalmobilecommunicationinUHF/VHFband.However,therearemanyproblemsinbothmobilechannels,suchasnoiseinterference,intersymbolinterferenceandselectivefadinginmultipathpropagation.Inordertosolvetheseproblems,abettermodulationmethod,OrthogonalFrequencyDivisionMultiplexing(OFDM),hasemerged.Thisnewmodulationmodeusesparalleltransmission,hashighchannelutilizationandgoodanti-fadingability.Itiswidelyusedinthefieldofmobilecommunicationandhasbecomethecoretechnologyofthefourthgenerationmobilecommunicationsystem.OrthogonalFrequencyDivisionMultiplexing(OFDM)signalsaremodulatedbyasetoforthogonalsinusoidalsignalsastheirsubcarriers,usingthenon-returnzerosquarewavewiththesymbolperiodTasitsbasebandcodetype.TheprocessofsignalgenerationanddemodulationinOFDMisthetransformationprocessofIDFT/DFT.Keywords:channelfrequencydivisionmultiplexing,OFDM,modulationmode1目录................................................................................................................1..................................................................................1..................................................................................................1.......................................................................................1....................................................................................2.............................................................................................3.............................................................................................3....................................................................................3...........................................................................................4.........................................................................................7...................................................................................7..............................................................................................7............................................................7........................................................8..............................................................................................9................................................................................11.............................................................................................12.............................................
