多输入多输出通信系统的信道模型及容量

I多输入多输出通信系统的信道模型及容量专业：通信工程摘要随着无线通信事业的迅速发展，用户对无线通信的速率和服务质量提出了越来越高的要求。然而频谱资源的匮乏限制了无线通信的进一步发展；另一方面，无线信道的多径传播特性和时变特性会对其中传输的信号带来非常大的损害。近年来多输入天线多输出天线（MIMO）技术因为能大幅度增加无线通信系统的谱效率和提高传输可靠性而得到了越来越多的关注。MIMO多天线系统所提供的空间复用增益和空间分集增益可以极大地提高无线链路的容量和质量。现有的研究成果己经表明，MIMO所能达到的极高的频谱效率是目前任何一种无线技术所不及的，因此它被认为是未来新一代移动通信系统的备选关键技术之一。根据信道的输入输出情况，使用多天线技术的通信系统可以分为单输入多输出SIMO（Single-InputMultiple-Output）系统、多输入单输出MISO（Multiple-InputSingle-Output）系统，以及多输入多输出MIMO（Multiple-InputMultiple-Output）系统三种类型。本文首先介绍了MIMO系统的基本概念和信道模型，然后我们从信息论的角度，根据传统SISO信道的香农容量，推导出MIMO信道容量公式，并且依次推导出SIMO信道和MISO信道的容量。本文对MIMO信道模型和信道容量的研究表明，MIMO技术对于未来新一代无线通信具有极其的重要意义。关键词：MIMO，SIMO，MISO，多天线系统，信道模型，信道容量。IIChannelModelandCapacityoftheMIMOCommunicationSystemsAbstractAsthewirelesscommunicationmakesrapidprogress,thedemandforhigherdataratesandhigherqualityinwirelesscommunicationsystemshasrecentlyseenunprecedentedgrowth.However,oneofthemostlimitingfactorsingrowthofwirelesscommunicationsisthescarcityofspectrum.Inaddition,themulti-pathpropagationandtimevariancecharacteristicsofwirelesschannelbringsomeimpairmenttothesignalstransmittedoverit.Inrecentyears,multipleinputmultipleoutput(MIMO)antennastechniquehasreceivedmoreandmoreattention,asitcandramaticallyincreasethespectralefficiencyandimprovethetransmissionreliabilityofwirelesscommunicationsystems.TheMIMOchannelgainofMIMOsystemsthatincludespatialmultiplexing(SM)gainandthespatialdiversity(SD)gaincanincreasegreatlythecapacityandthequalityofthewirelesslink,andtheresearchresultsshowspectralefficiencyofMIMOtechniqueishigherthananyotherexistingwirelesstechniques.SoMIMOtechniqueisconsideredasoneofcandidacytechniquesthatcanbeusedinthenextnewgenerationofmobilecellularcommunicationsystems.Anygivencommunicationsystemthatutilizesthemultipleantennatechniquecanbeclassifiedintothreecategories:singleinputmultipleoutput(SIMO),multipleinputsingleoutput(MISO)andmultipleinputmultipleoutput(MIMO)systemrespectively.ThispaperfirstlyintroducesthebasicconceptandmodelofMIMOchannel.Secondly,intheviewofinformationtheory,accordingtotraditionalSISOchannelShannoncapacity,wederivedthecapacityofMIMOchannel,MISOchannelandSIMOchannel.Inthispaper,thestudiesonMIMOchannelmodelandchannelcapacityshowthatMIMOtechniqueisvitaltothenewgenerationofwirelesscommunications.Keywords:MIMO,SIMO,MISO,MultipleAntennaSystem,ChannelModel,ChannelCapacity.III目录摘要·····································································································IAbstract····································································································II第一章绪论·······························································································11.1引言······························································································11.2无线移动通信的发展概述···································································11.3天线阵列在移动通信系统中的引入·······················································21.4MIMO技术综述·············································································3第二章多输入多输出通信系统信道模型···························································52.1通信系统模型··················································································52.2模拟通信系统模型············································································52.3数字通信系统模型············································································52.4无线信道传播环境············································································62.5几种常用的无线通信信道模型·····························································62.5.1高斯信道················································································72.5.2瑞利信道················································································72.5.3莱斯信道················································································72.6多输入多输出通信系统信道模型··························································72.6.1SISO信道···············································································72.6.2SIMO信道··············································································82.6.3MISO信道··············································································92.6.4MIMO信道·············································································9第三章多输入多输出通信系统信道容量·························································123.1MIMO系统模型的分解····································································123.2多输入多输出系统信道容量分析························································123.2.1SISO系统信道容量·································································133.2.2MIMO系统信道容量·······························································143.2.3SIMO系统信道容量································································163.2.4MISO系统信道容量································································17结论·······································································································19参考文献（References）··············································································20谢辞···········································