毕设—QPSK的调制解调

目录摘要..................................................................1ABSTRACT...............................................................2第1章绪论..........................................................41.1课题背景、目的及意义...........................................41.2课题的主要内容.................................................51.3本论文的结构安排...............................................5第2章调制解调技术.................................................62.1常见的调制解调技术..............................................62.2QPSK技术......................................................62.2.1QPSK原理.................................................62.2.2QPSK实际应用...........................................102.3比较联系......................................................112.4QPSK应用前景.................................................12第3章MATLAB简介..................................................133.1MATLAB概貌.....................................................133.1.1MATLAB的发展...........................................133.1.2Matlab的主要功能.......................................143.2MATLAB的优势及特点.............................................143.2.1Matlab的优势...........................................143.2.2Matlab语言的特点.......................................14第4章QPSK调制解调设计..............................................164.1设计步骤.......................................................164.2QPSK的调制解调...............................................174.3QPSK在高斯噪声情况下调制解调.................................214.4QPSK抗噪声性能仿真...........................................25第五章结论与总结...................................................27参考文献..............................................................28致谢................................................................29附录1代码..........................................................31附录2外文文献及翻译................................................39外文文献..........................................................39中文翻译..........................................................43附录3毕业设计任务书................................................46附录4开题报告......................................................48华北水利水电学院本科生毕业设计开题报告.............错误!未定义书签。1摘要在21世界信息飞速发展的时代，各个国家对通信行业的支持更是不遗余力。当前我国3G行业正值蓬勃发展，国家又在大力倡导三网融合。各个运营商都在极力扩展自己的业务。这也在为客户服务方面有了更高的要求、更高的质量。众所周知，调制解调技术是信号传输的基本和核心。好的技术能够快速地传递用户信息，并且有着高的准确性（即非常低的误码率）和可靠性。QPSK调制解调技术以其高的解调速率、低的误码率，在CDMA领域得到广泛应用。此项研究，对通信行业的发展有着积极推进的作用，利于提高我国通信行业的技术水准，以便于更好的为国家和人民服务。论文分作五部分，第一章是绪论，简单阐述QPSK课题的研究背景以及课题内容和整个论文的结构安排；第二章简单介绍了了QPSK调制解调的原理和方法，系统阐述了最常见的2ASK、2PSK、2FSK的原理和方法，最后再对他们做一个系统的比较，以便明白QPSK的优点和性能；第三章是对所用工具MATLAB做一个大概的阐述，讲解了MATLAB的发展、性能、所用于语言，以及在各个领域的应用。为后边编写程序做下准备、第四章针对此次课题QPSK的调制解调提出具体的方案，按调制和解调的步骤，一步步编写出程序，然后，利用MATLAB工具对程序做出相应的仿真，在仿真过程中加入噪声分析，最后在对它的误码率做一个研究；第五章是对整个毕设的结论和总结，感悟自己在这一时间内的所学所感，对自己的努力做一个回顾，以便在今后的生活和学习中，有更进一步的提高首先介绍了QPSK的调制解调原理，接着提出了一种基于MATLAB的调制解调方案，包括串并转换、电平转换、载波调制、信号合成、相干解调、抽样判决，和并串转换一系列系统的设计，对QPSK的星座图和调制解调进行了仿真，并对系统性能进行了分析，进而证明QPSK调制技术的优越性。关键字：QPSK调制解调电平转换相干解调抽样判决2AbstractInthetwenty-firstcentury,theinformationintheeraofrapiddevelopmentofvariouscountriesintheworld,andthecommunicationsindustrysupportissparenoeffort..Current,China3Gindustrywasbooming,andvigorouslypromotenationalintegrationinthe.Variousoperatorsaretryingtoexpandtheirbusiness.Thisisalsoforcustomerservicehadhigherdemand,higherquality.Aseveryoneknows,modulationanddemodulationtechnologyisthebasicandcoreofsignaltransmission.Goodtechnologycanrapidlytransfertheuserinformation,andwithhighaccuracy(i.e.,verylowbiterrorrate)andreliability.QPSKmodulationanddemodulationtechnologyforitshighdemodulationrate,lowerrorrate,havebeenwidelyappliedinCDMA.Inthisstudy,thecommunicationsindustrydevelopmenthasapositivepromotionrole,helpimproveChina'scommunicationindustrytechnicalstandards,inordertobetterserveourcountryandourpeople.Thepaperisdividedintofiveparts,thefirstchapteristheintroduction,introducedQPSKtheresearchbackgroundofthesubjectandtopiccontentandtheorganizationofthisthesis;thesecondchapterbrieflyintroducestheQPSKmodulationanddemodulationprincipleandmethod,thesystemelaboratedthemostcommon2ASK,2PSK,2FSKprincipleandmethod,finallytomakeoneasystematiccomparison,inordertounderstandtheadvantagesofQPSKandperformance;thethirdchapterisonthetoolusedMATLABdoprobablyexplain,explainthedevelopmentofMATLAB,performance,isusedforthelanguage,aswellasinthevariousfieldsofapplication.Forbehindtheprogramdopreparation,inthefourthchapterthetaskofmodulationanddemodulationofQPSKputforwardtheconcreteschemeaccordingtothemodulationanddemodulation,step,stepbysteppreparationprocedures,andthen,usingMATLABtoolstomakethecorrespondingsimulationprogram,intheprocessofsimulationaddingnoiseanalysis,atlastonitsbiterrorratedoastudy;Chapterfifthisonthewholecompletesetofconclusionsandsummary,feelingmyselfatthistimewhatare,ontheirowntodoareview,sothatinthefuturelifeandstudy,hasfurtherimprovedFirst,thearticlewillintroducetheQPSKmodulationanddemodulationprinciple,thenproposedonekindbasedontheMATLABmodulationanddemodulationoftheprogram,includingthestringandtheconversion,conversion,carriermodul