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单位代码01学号分类号TN912.3密级毕业设计论文语音信号增强技术的研究与仿真实现院（系）名称信息工程学院专业名称通信工程学生姓名指导教师2011年5月15日第I页语音信号增强技术的研究与仿真实现摘要语音信号处理是研究用数字信号处理技术对语音信号进行处理的一门新兴学科。语音信号处理的应用极为广泛，其中的主要技术包括语音编码、语音合成、语音识别和语音增强等，实际中，语音常常受到环境噪声的干扰而使通话质量下降，严重时使语音处理系统不能正常工作。在这种情况下，必须采用信号处理方法进行语音增强，抑制背景噪声，以提高语音通信质量。因此，就语音增强技术本文着重在抑制背景噪声上进行了研究和仿真。首先，对语音信号的各种处理技术进行了较为详细地介绍；其次根据对语音信号增强处理技术的分析，设计了一个用于抑制噪声的数字滤波器，从而达到了语音增强的目的。最后在MATLAB的环境中，对含噪声语音信号读入，然后通过设计的滤波器进行了仿真实现，使语音信号得到了增强。关键词：语音信号处理，语音增强，MATLAB第II页SpeechsignalprocessingtechnologyresearchandsimulationAuthor:ZhuChaojunTutor:TangHailingAbstractSpeechsignalprocessingisanewdevelopingdisciplinewhichhasaresearchonthespeechsignalusingthetechnologyofdigitalsignalprocessing.Theapplicationisverywidespread.Speechcoding,speechsynthesis,speechrecognitionandspeechenhancementaretheprimarykindsoftechnologyofspeechsignalprocessing.Actually,speechisoftendisturbedbyenvironmentalnoise.Sothatthespeechqualitywilldropdown.Ifitisserious,thespeechprocessingsystemwillworkunnormally.Underthiskindofcircumstances,wemustadoptsignalhandlingmathodtoenhancespeechsothatthenoisefrombackgroundcanbecontroled.Ifwedothis,thespeechqualitycanbeimproved.Soaboutspeechenhancementtechnology,thistextemphasizesonresearchandsimulationaboutthecontrolofbackgroundnoise.Firstly,wehaveintroducedvariouskindsofprocessingtechnologyindetail.Secondly,onthebasisofanalysisaboutthetechnologyofspeechsignalenhancementprocessing,wehavedesignedatransformfordigitalfiltertocontrolnoisesothattheobjectiveofspeechenhancementcanbemade.Finally,intheenvironmentofMATLAB,thespeechsignalthatcontainsnoisewillbereaded-in.Thenthroughthetransformfordigitalfilterthathasbeendevesedthesimulationcanberealized.Bymeansofthis,speechsignalwasenhancedindeed.Keywords:Speechsignalprocessing,speechenhancement,MATLAB第III页目录1绪论......................................................................................................................................11.1语音处理技术的概述.......................................................................................................11.1.1语音编码技术..........................................................................................................21.1.2语音合成技术..........................................................................................................31.1.3语音识别技术..........................................................................................................31.1.4语音增强技术..........................................................................................................51.2课题研究背景及意义.......................................................................................................61.3本文主要研究内容...........................................................................................................62语音及语音增强研究的基础.......................................................................................82.1语音增强概述...................................................................................................................82.2语音增强技术的基本理论..............................................................................................92.3常用的语音增强算法....................................................................................................102.4小结.................................................................................................................................113语音信号增强的实现...................................................................................................123.1语音信号的获取及相应处理........................................................................................123.1.1时域信号的FFT分析...........................................................................................123.1.2语音信号的获取....................................................................................................123.2针对语音信号的FIR数字滤波器的设计....................................................................153.2.1数字滤波器设计原理...........................................................................................153.2.2数字滤波器的设计步骤.......................................................................................153.2.3FIR滤波器与IIR滤波器的性能比较.................................................................153.2.4FIR数字滤波器的设计.........................................................................................163.2.5针对语音信号的FIR数字滤波器的设计...........................................................16第IV页3.3语音信号的增强处理....................................................................................................183.4小结.................................................................................................................................194结论.....................................................................................................................................20致谢.........................................................................................................................................21参考文献...............................................................................................................................22第1页1绪论1