摘要本课程设计主要解决信源编码和信道编码中的卷积码的数字调制，信源输出的模拟信号要转换成数字信号，就需要对信源信道进行编码译码操作，并通过Simulink软件进行设计与仿真，进行误码率分析。卷积码是一种性能优越的信道编码。它的编码器和译码器都比较容易实现，同时它具有较强的纠错能力随着纠错编码理论研究的不断深入，卷积码的实际应用越来越广泛。本文简明地介绍了卷积码的编码原理和译码原理。并在SIMULINK模块设计中，完成了对卷积码的编码和译码以及误比特统计整个过程的模块仿真。最后，通过在仿真过程中分别改变卷积码的重要参数来加深理解卷积码的这些参数对卷积码的误码性能的影响。经过仿真和实测，并对测试结果作了分析。得出了以下三个结论：（1）当改变卷积码的码率时，系统的误码性能也将随之发生变化。（2）对于码率一定的卷积码，当约束长度N发生变化时，系统的误码性能也会随之发生变化。（3）回溯长度也会不同程度上地影响误码性能。关键词：编译码器；simulink；设计与仿真卷积码；码率ABSTRACTThiscourseisdesignedtosolvesourcecodingandchannelcodingconvolutionalcodesinthedigitalmodulation,thesourceoutputanalogsignalsintodigitalsignalstobeconvertedtotheneedforthesourceandchannelcodinganddecodingoperations,andthroughtheSimulinksoftwaredesignandsimulation,andthebiterrorrateanalysis.Convolutionalcodeisasuperiorperformanceofchannelcoding.Itsencoderanddecoderarerelativelyeasytoimplement,andithasastrongerrorcorrectioncapability.Error-correctingcodingtheoryresearchwiththedeepeningofthepracticalapplicationofconvolutionalcodesmorewidely.Thisconciseintroductiontotheprinciplesofconvolutionalcodinganddecodingprinciples.SIMULINKmoduleinthedesign,completedthecodinganddecodingconvolutionalcodeandbiterrorstatisticsofthewholeprocesssimulationmodule.Finally,changesinthesimulationprocessofconvolutionalcodes,respectively,todeepenourunderstandingoftheimportantparametersoftheseparametersonconvolutionalcodesconvolutionalcodeserrorperformance.Thesimulationandmeasurement,andtestresultsareanalyzed.Reachedthefollowingthreeconclusions:(1)Whenthechangerateconvolutionalcode,thesystemerrorperformancewillsubsequentlychange.(2)Foracertainrateconvolutionalcodes,whentheconstraintlengthNchanges,thesystemBERperformancealsowillbechanged.(3)backlengthwillbeaffectedtovaryingdegrees,errorperformance.Keywords:codec;simulink;designandsimulationofconvolutionalcode目录第1章引言.........................................................11.1课题背景........................................................11.2国内外研究现状..................................................11.3本课题的意义....................................................11.4本课题的研究方法................................................2第2章MATLAB组件介绍及通信系统概述................................32.1MATLAB与通信仿真的发展现状及应用...............................32.2通信系统概述与组成..............................................32.3通信仿真........................................................42.4Simulink仿真及工作原理.........................................6第3章信源编码.....................................................83.1A律μ律编码特性...............................................83.1.1A律编码......................................................83.1.2μ律编码.....................................................83.1.3A律13折线...................................................93.2A律、μ律的特性比较..........................................11第4章信道编码及译码...........................
