数字化语音存储与回放系统的设计摘要:本文介绍的数字化语音存储与回放系统将完全可以替代传统的磁带语音录放系统。其基本原理是对语音的录音与放音的数字化控制。为了增加语音存储时间，提高存储器的利用率，采用了非失真压缩算法对语音信号进行压缩后再存储，而在回放时再进行解压缩，完成了对语音信号存储与回放。本文第1章是对课题的一些现状背景的介绍，2,3,4章是对整个系统设计的介绍。数字语音录放系统主要由三部分组成：第一，语音处理，包含编码和压缩；第二，语音录放系统的硬件设计；第三，语音录放系统的软件设计。经测试，本系统具有语音拾取，数字化存储和回放功能。对300Hz-3.4kHz范围内音频信号进行存储和回放，低频段效果较好，高频段稍差。通过提高采样频率，高频段音质可以得到改善。编码部分使用了简化的ADPCM，在一定压缩比下提高了放音时间和质量。AGC单元使放大器的增益随信号强弱而自动调整，很好地控制了输出相对稳定。带同滤波器合理的通带范围有效的滤除了带外噪声，减少了混叠失真。通过后级补偿电路对输出的语音信号进行了校正。回放语音清晰语音信号的回放与原语音信号相比，存在一定的失真，由于语音信号在采集与放音前分别经过一个带通滤波器，对于带通滤波器，带内平缓，带外陡峭不易同时达到，所以使语音信号有一定的失真。随着语音功能在电子信息业中的使用越来越普及，本系统必将有很广阔的应用前景。关键词：数字化存储，回放，数字滤波，采样，模/数转换，校正DesignofDigit-VoiceRecorderandPlaybackSystemAbstract:Thisarticledescribesadigitalvoicestorageandplaybacksystemcanreplacetraditionaltapevoicerecorderssystems.Thebasicprincipleistovoicerecordingandplaybackofdigitalcontrol.Inordertoincreasethevoicestoragetimeandimprovethememoryutilization,theuseofanon-losslesscompressionalgorithmtocompressthespeechsignalandthenstoredintheplaybackandthendecompressed,andcompletedthespeechsignalstorageandplayback.Chapter1ofthisarticleissubjectstatusofthebackgroundofsomedescription,2,3,4chapterisanintroductiontotheentiresystem.Digitalvoicerecordingsystemismainlycomposedofthreeparts:first,speechprocessing,includingencodingandcompression;second,voicerecordingsystemhardwaredesign;third,voicerecordingsystemsoftwaredesign.Aftertesting,thesystemhasvoicepicking,digitalstorageandplaybackcapabilities.Therangeof300Hz-3.4kHzaudiosignalstorageandplayback,betterlowfrequency,highfrequencysomewhatless.Byincreasingthesamplingfrequency,highfrequencysoundqualitycanbeimproved.CodingpartoftheuseofasimplifiedADPCM,inacertaincompressionratioandimprovedthequalityofplaybacktime.AGCamplifierunittoautomaticallyadjustwiththesignalstrength,goodcontroloftheoutputisrelativelystable.Thesamefilterwithareasonablerangeofeffectivefilterpassbandofthebandnoise,reducingthealiasingdistortion.Aftertheadoptionoftheoutputlevelcompensationcircuittocorrectthespeechsignal.Clearvoiceplaybackplaybackaudiosignalincomparisonwiththeoriginalspeechsignal,thereissomedistortioninthespeechsignalpriortoacquisitionandplaybackthroughaband-passfilter,respectively,forthebandpassfilter,withthegentle,easy-bandsteepAtthesametimetoachieve,sothatthereissomedistortionofthespeechsignal.Withthevoiceintheuseofelectronicinformationindustryisbecomingincreasinglypopular,thesystemwillhaveverybroadapplicationprospects.Keywords:Digitalstore，Playback，Digitalfilter，Sample，A/DConvert，Correcting引言语音信号处理属于信息科学的一个重要分支，大规模集成技术的高度发展和计算机技术的飞速前进，推动了这一技术的发展。在数字音频技术和多媒体技术迅速发展的今天，传统的磁带语音录放系统因体积大、使用不便、放音不清晰而受到了巨大挑战。采用单片机对语...
