16QAM调制解调系统的FPGA实现

CENTRALSOUTHUNIVERSITY本科生毕业论文(设计)题目QAM通信系统接收端混频与解调器的设计及其FPGA实现学生姓名尹海明指导教师盛利元教授学院物理科学与技术学院专业班级电子信息科学与技术0805班完成时间2012年6月7日中南大学学士学位论文摘要I摘要QAM(QuadratureAmplitudeModulation)是一种新的调制技术，它在调制过程中利用了相位和幅度两维空间资源，比只利用单一维度空间资源的PSK和ASK调制方式频谱利用率高，不仅如此，QAM的星座点比PSK的星座点更分散，星座点之间的距离因此更大，所以能提供更好的传输性能。随着第三代移动通信的兴起，传输容量增大，多进制正交幅度调制MQAM(MultipleQuadratureAmplitudeModulation)将得到更加广泛的运用。本文主要研究了基于FPGA的16QAM调制与解调的实现。首先说明了QAM调制和解调的原理，用SystemView软件建立16QAM调制解调系统模型，然后对各系统组成模块分析与仿真之后提出基于FPGA的16QAM调制与解调的总体设计方案。最后用Verilog语言编写程序完成了整个系统的仿真，并对编好的程序其进行了编译调试。文中详细介绍了载波恢复、正交相干解调、FIR低通滤波器和采样判决的基本原理和设计方法。首先用SystemView对16QAM调制解调总体进行了系统仿真；然后用Verilog语言在QuartusII软件平台下完成了系统各功能模块的编写、功能与时序仿真和综合，最后把各模块组成的顶层原理图编译成的程序下载到EP2C35F672C6N芯片上，手动输入基带信号，经过芯片处理后，基带信号得以有效恢复。关键词：正交相干解调，混频，FPGA，QAM，SystemView中南大学学士学位论文ABSTRACTIIABSTRACTQAM(QuadratureAmplitudeModulation)isanewmodulationtechnique,becauseoftheuseofphaseandamplitudetwo-dimensionalspaceresourcesinthemodulationprocess,ithasahigherefficiencythanPSKandASKmodulationwitchuseonlyasingledimensionofspaceresources.Moreover,theQAMconstellationpointsofPSKconstellationpointsmoredispersed,thedistancebetweentheconstellationpointsistherefore,soitisabletoprovidebettertransmissionperformance.Withtheriseofthirdgenerationmobilecommunicationandthetransmissioncapacityincreases,M-aryquadratureamplitudemodulationofMQAM(MultiplequadraturetheAmplitudeModulation)willbemorewidelyused.ThispaperstudiestherealizationofFPGA-based16QAMmodulationanddemodulation.Firstly,theprincipleofQAMmodulationispresented,andthemodelingofthe16QAMmodulation&demodulationsystemisbuiltwiththeSystemViewsoftware.Then,bywayofanalyzingsystemcompositionmodulesandpartialsimulation,thedesignofthel6QAMmodulationsystembasedonFPGAisputforwards.FinallythewholesystemsimulationisrealizedwithVerilog,Andprogrammedtocompiledebug.Inthispaper,theprincipleanddesignmethodofcarrierrecovery,quadraturecoherentdemodulator,FIRlowpassfilterandsamplinganddecisionaredetailedlyintroduced.Firstly,Thesystemof16QAMissimulatedwithSystemView.Then,eachfunctionalmoduleisimplementedwithVerilogHDLontheQuartusIIsofiwareflat,andthefunction&timingsimulationandthesynthesisarefinished.Finally,theprogramcompiledfromthetopschematicdiagramisdownloadedtotheEP2C35F672C6Nchipandwhenmanuallyenteredthebasebandsignal,thesignalcanbeeffectivelyrecovered.Keywords:Quadraturecoherentdemodulation,Mixer,FPGA,QAM,SystemView中南大学学士学位论文目录III目录摘要..........................................................................................................................IABSTRACT.................................................................................................................II目录........................................................................................................................III第一章绪论...........................................................................................................11.1课题研究背景及意义..................................................................................11.2QAM技术发展概要及应用现状................................................................21.3本文内容和结构..........................................................................................2第二章发射及接收端概述及整体设计...............................................................42.1QAM调制解调的原理与性能....................................................................42.1.1QAM调制原理.........................................................................................42.1.2QAM的解调方法和原理.....................................................................62.1.3QAM的误码率性能..........................................................................72.2发送端和接收端的SYSTEMVIEW软件仿真.........................................7第三章混频及解调器分模块设计.....................................................................133.1混频模块设计............................................................................................133.1.1DDS载波恢复模块设计.....................................................................133.1.2乘法器模块设计.................................................................................153.2QAM解调模块设计..................................................................................163.2.1低通滤波器模块设计.........................................................................163.2.2采样判决模块设计.............................................................................173.2.3电平转换模块设计.............................................................................173.3总线位宽转换模块设计............................................................................18第四章混频及解调器QUARTUSII仿真调试...................................................194.1FPGA概述.................................................................................................19中南大学学士学位论文目录IV4.2DDS载波恢复模块....................................................................................204.3乘法器模块................................................................................................224.4低通滤波器模块........................................................................................234.5采样判决模块.................