基于FPGA的数字调制解调器设计基于FPGA的数字调制解调器设计摘要本设计使用FPGA在EDA技术开发软件QuartusⅡ上实现以正弦信号为载波的三种调制信号ASK、FSK、PSK的调制和解调。系统采用ALTERA公司生产的DE2开发板，CycloneIIEP2C35F672C6型号的FPGA和EPCS16系列的配置驱动，使用VHDL硬件描述语言实现，系统时钟为50MHZ，经四分频产生一路时钟信号经过DDS波形发生器形成ASK，PSK及FSK的一路载波，FSK的另一路载波由系统时钟经八分频后经过DDS波形发生器后产生。由于ASK和PSK调制特性相近，载波都为一路信号。因此在设计时将ASK和PSK调制放在同一模块里设计，用一个选择键和两个基带信号控制端来控制。系统时钟经过512分频后经过随机信号模块产生一路周期为15的伪随机序列作为数字调制的基带信号。在解调时，用非相干解调法解调ASK和PSK信号，用过零检测法解调FSK信号。经过功能仿真和验证后，测试输出信号与基带信号是否相符。关键词：FPGA,ASK,PSK,FSKDigitalmodulationanddemodulationbasedonFPGAAbstractThisdesignusesFPGAonEDAtechnologydevelopmentplatformQuartusⅡtoachievethegenerationandthedemodulationofthreemodulationsignal——ASK,FSK,PSKascarrierthroughsinusoidalsignals.ThesystemusestheALTERAcompany'sDE2developmentboard,FPGAofTypeCycloneIIEP2C35F672C6FPGAanddriverconfigurationofEPCS16series.ThissystemisrealizedinVHDLhardwaredescriptionlanguage,whoseASK,PSKandFSKcarrierisgeneratedwhenthefourfrequencyproducesaclocksignalthroughtheDDSwaveformgenerator,andthesystemclockis50MHZ.BecausethecharacteristicsofASKandPSKmodulationaresimilartoeachother,whichmeanstheircarrierarebothonewaysignal,themodulationofASKandPSKareputonthesamemodelwhendesigned,withaselectionkeyandthetwobasebandsignalcontrolendscontrolling.Systemclockgeneratespseudorandomsequencebasebandsignalswhoseoneroadcycleis15asbasebandsignalsthroughrandomsignalmodelafterthe512frequencydivision.Wheninmodulation,weusenoncoherentdemodulationtodemodulateASKandPSKsignal,andthezerocrossingdetectionmethodforFSKsignaldemodulation.Afterthesystemistestedthroughthefunctionsimulationandverification,whethertheoutputsignalandthebasebandsignalareconformedtoeachotherornotwillbetestedKeywords:FPGA,ASK,PSK,FSK目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc328059377"1绪论PAGEREF_Toc328059377\h1HYPERLINK\l"_Toc328059378"1.1课题背景与研究现状PAGEREF_Toc328059378\h1HYPERLINK\l"_Toc328059379"1.1.1数字调制解调背景知识PAGEREF_Toc328059379\h1HYPERLINK\l"_Toc328059380"1.1.2FPGA背景知识PAGEREF_Toc328059380\h2HYPERLINK\l"