【毕业设计】基于FPGA的DDS信号发生器-精品

I基于FPGA的DDS波形发生器姓名:张怡专业班级:电子2班指导教师:易诗摘要波形发生器己成为现代测试领域应用最为广泛的通用仪器之一，代表了波形发生器的发展方向。随着科技的发展，对波形发生器各方面的要求越来越高。近年来,直接数字频率合成器（DDS）由于其具有频率分辨率高、频率变换速度快、相位可连续变化等特点,在数字通信系统中已被广泛采用而成为现代频率合成技术中的佼佼者。现场可编程门阵列（FPGA）设计灵活、速度快，在数字专用集成电路的设计中得到了广泛的应用，由于现场可编程门阵列(FPGA)具有高集成度、高速度、可实现大容量存储器功能的特性，能有效地实现DDS技术，极大的提高波形发生器的性能，降低生产成本。在现代电子器件,通信技术,医学成像,无线PCS/PCN系统,雷达,卫星通信中，具有很广泛的应用。本文首先介绍了DDS波形发生器的研究背景和DDS的理论。然后详尽地叙述了在以FPGA芯片为主的硬件平台上设计，编程实现一个DDS信号源，并产生不同通信中用到的调制信号(ASK，FSK，PSK),最后通过JTAG方式将产生的三种调制信号数据传送到电脑上,借助Quartus2软件中的嵌入式逻辑仪对结果进行观察与分析。通过分析结果表明，本设计达到了预定的要求，证明了采用软硬结合的方式，结合DDS技术，通过对FPGA的编程实现产生多种波形（如ASK，FSK，PSK）的DDS的方法是可行的。关键词：直接数字频率合成DDS现场可编程门阵列FPGA波形发生器IIDDSwaveformgeneratorbasedonFPGAAbstract:Waveformgeneratorhasbecomeamodernfieldtestoneofthemostwidelyusedgeneral-purposeequipment,onbehalfofthewaveformgeneratordevelopment.Withthedevelopmentoftechnologyinallaspectsofthewaveformgeneratorshavebecomeincreasinglydemanding.Inrecentyears,directdigitalsynthesizers(DDS)hasafrequencyresolutionbecauseofitshigh-frequencyconversionspeed,continuouschangesinthephasecharacteristicsindigitalcommunicationsystemshavebeenwidelyusedinmodernfrequencysynthesistechnologytobecometheleaderin.Field-programmablegatearray(FPGA)designflexibility,highspeed,indigitalASICdesignhasbeenwidelyused,duetofield-programmablegatearray(FPGA)withhighintegration,high-speed,largecapacitymemorycanberealizedfunctionalcharacteristics,caneffectivelyachieveDDStechnology,whichgreatlyimprovetheperformanceofwaveformgeneratorandreduceproductioncosts.ThispaperintroducestheDDSwaveformgeneratoroftheresearchbackgroundandDDStheory.ThenintroduceadetaileddesignbasedonFPGA,programmingaDDSsignalsource,andproducedifferentmodulationsignalsusedincommunication,suchasASK,FSK,PSK.Thelastsendingthethreekindofmodulationsignalstocomputerbyserialcommunication,thenusingQuartus2softwareembeddedlogicanalyzerontheresultsofobservationandanalysis.Byanalyzingtheresults,itshowthatthedesignmeetstherequirementsintendedto.AndProvedthatusingFlexwaytoprogrammingtheFPGAtoproduceavarietyofwaveforms(suchasASK,FSK,PSK)ofDDSisfeasible.Keywords：DDSFPGAWaveformGeneratorIII目录第1章前言..............................................................................................................11.1课题背景..........................................................................................................11.2国内外波形发生器发展现状..........................................................................11.2.1波形发生器的发展现状.......................................................................11.2.2国内外波形发生器产品比较...............................................................21.2.3研究波形发生器的目的及意义...........................................................21.3本文研究主要内容..........................................................................................2本章小结................................................................................................................2第2章DDS波形发生器理论介绍...........................................................................32.1频率合成技术.................................................................................................32.1.1频率合成技术发展与分类...................................................................32.1.2频率合成技术指标...............................................................................42.1.3频率合成的技术现状...........................................................................52.2DDS基本原理与特点.....................................................................................62.2.1DDS基本原理......................................................................................62.2.2DDS优点..............................................................................................72.2.3DDS缺点..............................................................................................7本章小结................................................................................................................7第3章数字调制信号介绍......................................................................................83.1概述..................................................................................................................83.2调制方式..........................................................................................................83.3ASK幅移键控.................................................................................................93.4PSK相移键控...............................................................................................103.5FSK频移键控..............................................................................................11本章小结..............................................................................................................11第四章开发平台介绍................................................................................................124.1硬件平台FPGA介绍..................................................................................124.1.1FPGA简介.........................................................................................124.1.2FPGA工作原理.................................................