通信与电子信息科技英语 总.ppt

Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.samplefunction2.ensembleaverage3.physicalsignificance4.aFhelimit7.timeinvariant8.anupperfrequencylimit9.Parsevalstheorem10.randompulses,样本函数,总体均值,物理意义,傅立叶变换对,确定性波型,在极限情况下,时不变的,频率上限,巴塞瓦尔定理,随机脉冲,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.随机过程2.统计平均3.随机变量4.自相关函数5.傅里叶变换6.功率谱密度7.概率密度函数8.高斯过程9.平稳过程10.统计独立,randomprocess,statisticalaverage,randomvariable,autocorrelationfunction,Fouriertransform,powerspectraldensity,probabilitydensityfunction,gaussianprocess,astationaryprocess,statisticallyindependent,11.时间平均(值)12.统计特性13.各态历经过程14.狄拉克函数,timeaverage,statisticalcharacteristic,ergodicprocess,deltafunction,Exercises,.Fillintheblankswiththemissingword(s).1.Theensembleaverageswillbeidenticalthestatisticalaveragesandmayberepresentedbythesamesymbols.2.TheaveragesdeterminedbymeasurementsasinglesampleFunctionsuccessivetimeswillyieldatimeaverage,whichwerepresentasn2(t1).3.Suppose,forexample,thatthestatisticalcharacteristicsofthesampleFunctionstheensemblewerechangingwithtime.4.Foritmayhappenthatwhileeachsamplefunctionisstationarytheindividualsamplefunctionsmaydifferstatisticallyoneanother.5.Asanextensionofthatresultweshalldefinethepowerspectraldensityofarandomprocessthesameway.,with,on,at,in,from,in,Exercises,6.ItisinteresttoinquirewhetherG(f)definedEq.(1.2)forarandomprocesshasaphysicalsignificancewhichcorrespondstothephysicalsignificanceofG(f)fordeterministicwaveforms.8.Hence,ifweshouldselectsomesamplefunction,aknowledgeofthevalueofn(t)attimetwouldbenoassistanceimprovingourabilitytopredictthevalueattainedbythatsamesamplefunctionattimet+.9.Hence,wheneverwemakeanobservationormeasurementofthepulsewaveformwhichextendsadurationlongenoughsothattheaverageobservedpulseshape,suchastheiramplitudes,widths,andspacingsarerepresentativeofthewaveformgenerally,weshallfindthatEq.(1.12)applies.,of,in,of,in,over,Exercises,10.Letusselectasectionofthiswaveformwhichextends-T/2-T/2.11.Sincewehaveassumedanergodicprocess,weareatlibertyto(perform,performing)theaveraginganysamplefunctionoftheensemble,sinceeverysamplefunctionwillyieldthesameresult.,to,from,perform,over,.PleasetranslatethefollowingwordsandphrasesintoCbabilitydensity7.rootmeansquare8.tradeoff9.lowerbound1.equalizer11.viceversa12.upperlimit,Exercises,物理系统，实际系统上升时间信息量理论上，原则上高斯信道概率密度均方根值,均方根；均方根(的)交替换位，折衷选择下界,下限均衡器反之亦然上限,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.通信理论2.香农定理3.信道带宽4.信号波形5.理想低通滤波器6.自相关函数7.无噪声高斯信道8.通信信道9.信息速率10.信噪比,Exercises,communicationtheory(theoryofcommunications)ShannonstheoremchannelbandwidthsignalwaveformideallowpassfilterautocorrelationfunctionnoiselessgaussianchannelcommunicationchannelinformationrateSignaltonoiseratio（SNR,S/N）,Exercises,11.信道容量12.双边功率谱密度13.误码率14.奈奎斯特采样速率15.限带高斯信道16.高斯白噪声,channelcapacityTwosidedpowerspectraldensityerrorprobability(probabilityoferror)NyquistsamplingratebandlimitedgaussianchannelwhiteGaussiannoise,Exercises,.Fillintheblankswiththemissingword(s).1.ThereisanegativestatementassociatedShannonstheorem.2.thepurposeoftransmissionoverthechannel,themessagesarerepresentedbyfixedvoltagelevels.3.SincethetransmissionofanyoftheMmessagesisequallylikely,H=log2M,thusourchannelistransferringinformationarateR=rH.4.Forafixedsignalpowerandthepresenceofwhitegaussiannoisethechannelcapacityapproachesanupperlimitwithincreasingbandwidth.5.Itisgreatinteresttorecognizethatthetradeoffbetweenbandwidthandsignaltonoiseratioisnotlimitedbyalowerlimitbandwidth.,with,on,at,in,of,in,Exercises,6.ThesignalistransmittedachannelwhichcanberepresentedasalowpassRCcircuitwithcutoffat1Hz.7.Ifthereisnonoise,thenweareentirelyfreetomakefortheattenuationbytheuseofanamplifierandtocorrectthefrequencydistortionbytheuseofanequalizer.8.Thatis,weneedtoestimatetheintervalTwhichshouldbeassignedtoeachmessagetoallowthetransmittedlevelstoberecognizedIndividuallythereceiver,eventhoughthebandwidthBofthechannelislimited.9.Therefore,the25percentreductionbandwidthrequiresa60percentincreasesignalpower.,in,as,in,of,over,Exercises,10.Whilewehaveusedthetermcommunicationchannelmanyoccasions,itiswelltoemphasizeatthispoint,thattheterm,whichisSomethinganabstraction,isintendedtoencompassallthefeaturesandcomponentpartsofthetransmissionsystemwhichintroducenoiseorlimitthebandwidth.11.TheprobabilityoferroriscloseunityforeverypossiblesetofMtransmittersignals.12.ItturnsouttheresultsobtainedforagaussianchanneloftenprovidealowerboundtheperformanceofasystemOperatinganongaussianchannel.,in,that,in,to,in,as,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.overallperformance2.crestfactor3.nonlinearoperation4.inverseoperation5.rms6.PAM7.PDM8.PPM9.maximummagnitude10.errorintervals11.Entropy12.roundoff13.quantumlevel14.DPCM,Exercises,总性能振幅(波峰)因数(振幅与有效值之比)非线性运算逆操作均方根(值)脉幅调制(pulseamplitudemodulation)脉宽调制(pulsedurationmodulation)脉(冲相)位调制(pulsephasemodulation)最大幅值误差间隔熵,平均信息量舍入，用四舍五入化为整数量化电平差分脉冲编码调制(differentialpulsecodemodulation),Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.正脉冲2.脉冲编码调制3.解码器4.编码器5.量化步长6.峰值7.线性函数8.脉冲序列9.均匀量化器10.预测编码11.压扩器12.压缩比,positivepulsepulsecodemodulation(PCM)decoderencoderquantumstepsizepeakmagnitudeslinearfunctionpulsetrainuniformquantizerpredictivecodingCompandorcompressionratio,Exercises,.Fillintheblankswiththemissingword(s).1.PCMisawidelydifferentformofmodulationcomparedwiththeanalogpulsetypessuchPAM,PDM,andPPM.2.Thecharacteristicsofthepulsegrouparerelatedthemessagesamplethroughoperationscalledquantizationandcoding.3.Thetermsymbolcoderdistingnishesthiscodingoperationtheoverallsourceencodingprocess.Inmostcases,avariablelengthcodeisusedtorepresentthemappedandquantizeddataset.Itassignstheshortestcodewordsthemostfrequently(occurring,occure,occurred)outputvaluesandthusreducescodingredundancy.4.Thus,aquantizationerrorexistsPCMand,aswillbeseen,istheBasiclimitationinperformance.5.Quantizationandsamplingproducethesameresultsamplingandquantizing.,as,to,from,to,occuring,in,as,Exercises,6.Forequalpeakmagnitudes,signalswithlargecrestfactorsgivepoorerperformancethosewithsmallKcr.7.Inthereceivertheinverseoperationisimplementedanexpandorrestoretheoriginalmessage.8.Thedigitaldataisfedseriallythedecoder.9.theratedrops,samplesaremadelessfrequentlyandstepsizesincrease.10.Theactualcompressionratioresultingthismethodisnomorethananorderof41.11.Inanattemptto（reduce，reducing）thenumberofcodessentbyaPCMsystem,aslightvariancesamplingmethodisusedbyasystemknownDifferentialPulseCodeModulation(DPCM).,than,by,to,into,as,from,reduce,on,as,Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.channelcoding2.transmissionbandwidth3.Singlesidednoisepowerdensity4.orthogonalsignaling5.FEC6.logictable7.systematiccode8.AWGN,信道编码传输带宽单边带噪声功率密度正交信号前向纠（forwarderrorcorrection)逻辑表系统码加性高斯白噪声(additivewhiteGaussiannoise),Exercises,9.BER10.trellisdiagram11.constraintlength12.vectorarray13.algebraicfunction14.statediagram15.cyclicshift16.generatormatrix,误码率,误比特率(BitErrorRatio)网格图制约长度向量数组(矩阵)代数函数状态图循环移位生成矩阵,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.检错码2.信道容量3.分组码4.卷积码5.移位寄存器6.汉明距离7.码重8.树形图9.编码增益,errordetectioncodeschannelcapacityblockcodesconvolutionalcodesshiftregisterHammingdistancecodeweight(weightofacode)treediagramcodinggain,Exercises,10.平均比特能量11.码距12.纠错码13.带宽效率14.模2加法器15.原始数据16.编码率17.生成多项式18.循环码,averagebitenergycodedistance(distanceofacode)errorcorrectioncodesbandwidthefficiencymodulo2adderrawdatacoderategeneratorpolynomialcycliccodes,Exercises,.Fillintheblankswiththemissingword(s).1.Channelcodingprotectsdigitaldataerrorsbyselectivelyintroducingredundanciesinthetransmitteddata.2.Byproperencodingoftheinformation,errorsinducedanoisychannelcanbereducedanydesiredlevelwithoutsacrificingtherateofinformationtransfer.3.Errorcontrolcodingwaveforms,theotherhand,havebandwidthexpansionfactorsthatgrowonlylinearlythecodeblocklength.4.Inablockencoder,kinformationbitsareencodedncodebits.,from,by,to,on,with,into,Exercises,5.Theblockcodeisreferredtoan(n,k)code,andtherateofthecodeisdefinedRc=k/nandisequaltherateofinformationdividedbytherawchannelrate.6.Convolutionalcodesarefundamentallydifferentblockcodesinthatinformationsequencesarenotgroupeddistinctblocksandencoded.7.Thetreediagramshowsthestructureoftheencodertheformofatreewiththebranches（represent，represented，representing）thevariousstatesandtheoutputsofthecoder.8.ThisreducesthebandwidthefficiencyofthelinkhighSNRconditions,butprovidesexcellentBERperformancelowSNRvalues.9.Asystematiccodeisonewhichtheparitybitsareappendedtheendoftheinformationbits.10.Achannelcoderoperatesdigitalmessage(orsource)databyencodingthesourceinformationacodesequencefortransmissionthechannel.,as,to,as,from,into,in,representing,in,at,in,to,on,into,through,Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.AM2.DPSK3.PAM4.PDM5.PPM6.PCM7.DPCM8.ASK9.FSK10.FDM11.TDM12.codedmodulation13.suppressedcarrier14.modulatedsignal,幅度调制(amplitudemodulation)差分相位键控(DifferentialPSK)脉(冲振）幅调制(pulseamplitudemodulation)脉宽调制(pulsedurationmodulation)脉（冲相）位调制(pulsephasemodulation)脉(冲编)码调制(pulsecodemodulation)差分脉冲编码调制(differentialpulsecodemodulation)振幅键控(amplitudeshiftkeying)移频键控(frequencyshiftkeying)频分（多路）复用(frequencydivisionmultiplexing)时分（多路）复用(timedivisionmultiplexing)编码调制抑制载波已调信号,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.带通信号2.脉冲调制3.角度调制4.残留边带抑制载波调制5.绝对带宽6.脉冲宽度7.线性函数8.载波频率9.模拟调制10.移相键控11.连续波调制12.同轴电缆,bandpasssignalpulsemodulationanglemodulationVestigialsidebandsuppressedcarriermodulationabsolutebandwidthpulsedurationlinearfunctioncarrierfrequencyanalogmodulationPSK(phaseshiftkeying)continuouswave(cw)modulationcoaxialcable,Exercises,.Fillintheblankswiththemissingword(s).1.Themethodinvolvesfirstsamplingtheinformationsignal,quantizingthesamplebyroundingofftotheclosestofanumberofdiscretelevels,andfinallygeneratingaprescribednumberofpulsesaccordingtoacoderelatedtothenearestdiscretelevel.2.Codedmodulationwillalsobereferredtoasdigitalmodulation.Itisoneofthemostmodernandusefulmethodsofmodulationavailabletoday.3.InPPMpulsepositionisproportionaltotheamplitudeofthemessagesignal4.Timedivisionmultiplexing(TDM)usespulsemodulationtoputsamplesofdifferentsignalsinnonoverlappingtimeslots.Forinstance,thegapsbetweenpulsescouldbefilledwithsamplesfromothersignals.5.Itisoftennecessarytousemodulationtotranslatetheusefulbandoffrequenciesuptoalargecarrierfrequencysothatefficientelectromagneticradiationispossiblefromanantennahavingreasonablesize.,Exercises,6.Thedesignofacommunicationsystemmaybeconstrainedbythecostandavailabilityofhardware,whoseperformanceoftendependsonthefrequenciesinvolved7.Fractionalbandwidthconsiderationsaccountforthefactthatmodulationunitsarefoundinreceiversaswellasintransmitters.8.Thesemethodsmaybecharacterizedascontinuouswave(cw)modulation.9.Sinceeachstationhasadifferentassignedcarrierfrequency,thedesiredsignalcanbeseparatedfromtheothersbyfiltering.10.PCMmaybeeitherbinary,wherepulseshaveonlytwovoltagelevels,or-ary,wherepulsesmaytakeonpossiblelevels.11.Byexploitingthefrequencytranslationpropertyofcwmodulation,messageinformationcanbeimpressedonacarrierwhosefrequencyhasbeenselectedforthedesiredtransmissionmethod.,Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.copperwire2.speechrecognition3.adaptivedifferentialPCM4.infiniteimpulseresponse(IIR)5.realtimeconversation6.digitalsignalprocessing7.CELP8.VAD9.MPE10.ADPCM11.directquantization12.logpulsePCMquantizer,铜线语音识别自适应差分脉码调制无限脉冲响应实时交谈数字信号处理码激励线性预测（codeexcitedlinearprediction)话音激活检测器(voiceactivitydetector)多脉冲激励(multipulseexcitation)自适应差分脉码调制(adaptivedifferentialPCM)直接量化对数脉冲PCM量化器,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.共振峰跟踪滤波器2.国际电信联盟3.背景噪声4.双向通信5.基音跟踪滤波器6.长时预测7.语音编码8.声码器9.语音增强10.波形跟随编码器11.参数编码器12.频域编码器,铜线语音识别自适应差分脉码调制无限脉冲响应实时交谈数字信号处理码激励线性预测（codeexcitedlinearprediction)话音激活检测器(voiceactivitydetector)多脉冲激励(multipulseexcitation)自适应差分脉码调制(adaptivedifferentialPCM)直接量化对数脉冲PCM量化器,Exercises,.Fillintheblankswiththemissingword(s).1.Speechcodingisafundamentaltechnologythathasexistedformorethan60years,beginninginthe1930swithDudleysoriginalvocoder.2.Speechcodingisdistinctfromthemoregeneralproblemofaudiocodinginthattheprimarysignalofinterestisthespeechitself.3.Virtuallyallexistingtelecommunicationsapplicationsbeginwithspeechcodedbythisstandard.4.Theselectionofappropriateexcitationpulsesiscarriedoutinaperceptuallyweighteddomain,ratherthanjustminimizingthemseinthewaveformdomainsothatthequantizationnoiseislessaudibletothelistener.5.Signaldelayisameasureofthedurationofthespeechsignalusedtoestimatecoderparametersreliablyforboththeencoderandthedecoder,plusanydelayinherentinthetransmissionchannel.,Exercises,6.Iftheroundtripdelayisheld(holds,isheld,held)below300msandthereissufficientechocancellation,thequalityisquiteacceptable.7.Ifthenumberofbitsprovidedbythecoderovertimeisalwaysthesame,therateisfixed.8.Voiceactivitydetectors(VAD)thatattempttodeterminewhetherspeechisactuallypresentsoastoutilizethechannelmoreefficientlywhenspeechisabsentandtoavoidtrying(totry,try,trying)tocodebackgroundsignalsasspeech.9.Instead,thisclassattemptstoproduceasignalthatsoundsliketheoriginalbyusingaparametricmodelofspeech,analying(analyzing,analyze,analyzed)thespeechtoestimatetheseparameters,andthenquantizingonlytheparameters.10.Frequencydomaincodershavebeenselected(select,havebeenselected,areselecting)asthebasisforanewwidebandcodingrecommendationbytheITU-T.,Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.electromagnetic(EM)spectrum2.electronmicroscopy3.radiowave4.ultrasound5.imageunderstanding6.framebuffer7.imagesensor8.fileextensions,电磁波频谱电子显微镜无线电波超声(波)图像理解帧缓存器，帧缓冲摄像传感器文件扩展名,Exercises,9.JPEG10.transmissioncapacity11.boundaryrepresentation12.featureselection13.ALU14.archivalstorage15.stereodisplay16.specializedhardware17.artificialintelligence18.flatscreen,联合图像专家组(JointPhotographicExpertsGroup)传输容量边界表示（法）特征选择算术逻辑单元，运算器(arithmeticlogicunit)档案库存储器立体显示专用硬件人工智能(AI)平面屏幕,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.数字图像处理2.像素3.海量存储器4.图像分析5.图像锐化6.图像恢复7.数据压缩8.对比度增强,digitalimageprocessingpixel(pel,pictureelement,imageelement)massstorageimageanalysisimagesharpeningimagerestorationdatacompressioncontrastenhancement,Exercises,9.分辨率10.图像显示11.卫星图像12.光盘13.小波14.计算机视觉15.图像退化16.图像采集17.磁盘18.目标识别,Resolutionimagedisplaysatelliteimageopticaldisk(opticaldisc)waveletcomputervisionimagedegradationimageacquisitionmagneticdiskobjectrecognition,Exercises,.Fillintheblankswiththemissingword(s).1.Thefieldofdigitalimageprocessingreferstoprocessingdigitalimagesbymeansofadigitalcomputer.2.Theseelementsarereferredtoaspictureelements,imageelements,pels,andpixels.3.Visionisthemostadvancedofoursenses,soitisnotsurprisingthatimagesplaythesinglemostimportantroleinhumanperception.4.Sometimesadistinctionismadebydefiningimageprocessingasadisciplineinwhichboththeinputandoutputofaprocessareimages.5.Alowlevelprocessischaracterizedbythefactthatbothitsinputsandoutputsareimages.6.Imageacquisitioncouldbeassimpleasbeinggivenanimagethatisalreadyindigitalform.,Exercises,7.Itisimportanttokeepinmindthatenhancementisaverysubjectiveareaofimageprocessing.8.Imagecompressionisfamiliar(perhapsinadvertently)tomostusersofcomputersintheformofimagefileextensions.9.Segmentationprocedurespartitionanimageintoitsconstituentpartsorobjects.10.Forexample,underthisdefinition,eventhetrivialtaskofcomputingtheaverageintensityofanimagewouldnotbeconsideredanimageprocessingoperation.11.Weconcludeourcoverageofdigitalimageprocessingwiththedevelopmentofmethodsforrecognitionofindividualobjects.12.Indedicatedapplications,sometimesspeciallydesinged(design,designed,designing)computersareusedtoachievearequiredlevelofperformance,butourinteresthereisongeneralpurposeimageprocessingsystems.,Exercises,.PleasetranslatethefollowingwordsandphrasesintoChinese.1.matrixcomputation2.controlsystemdesign3.earthandlifescience4.openarchitecture5.I/O6.structuredlanguage7.matrixfactorization8.imageprocessingtoolbox9.addon10.curvefitting,矩阵计算控制系统设计地球和生命科学开放型结构输入/输出(Input/Output)结构化语言矩阵因数分解图像处理工具箱附加曲线拟合(法),Exercises,11.externalroutine12.timeconsuming13.descriptivestatistics14.PDE15.geographicmapping16.datastructure17.stateoftheart18.GUI19.OOP20.iterativemethod,外部（例行）程序耗费时间的,旷日持久的描述统计(学)偏微分方程（partialdifferentialequation)地理制图数据结构目前发展水平；发展现状图形用户接口（graphic(al)userinterface)面向对象程序设计(objectorientedprogramming)迭代法,Exercises,.PleasetranslatethefollowingwordsandphrasesintoEnglish.1.矩阵2.数值积分3.数据采集4.线性代数5.部分分数展开6.嵌入式界面7.奇异值8.常微分方程9.稀疏矩阵10.面向对象的程序设计11.初值12.特征向量,MatrixnumericalintegrationdataacquisitionlinearalgebrapartialfractionexpansionbuiltininterfacesingularvaluesODE(ordinarydifferentialequation)sparsematrixOOP(ObjectOrientedProgramming)initialvalueeigenvector,Exercises,.Fillintheblankswiththemissingword(s).1.MATLABhasevolvedoveraperiodofyearswithinputfrommanyusers.2.SimulinkprovidesablockdiagraminterfacethatisbuiltonthecoreMATLABnumeric,graphics,andprogrammingfunctionality.3.UsershavefoundthatthecombinationoftheintuitiveMATLABinterface,language,andthebuiltinmathandgraphicsfunctionsmakeMATLABthepreferredplatformfortechnicalcomputingcomparedtoC,Fortran,andotherlanguagesandapplications.4.Usingthebuiltinmathandgraphicsfunctionsandeasytousetools,youcananalyzeandvisualizeyourdataonthefly.5.Thesealgorithms,developedbyexpertsinmathematics,arethefoundationoftheMATLABlanguage.,Exercises,6.Themathisoptimizedformatrixandvectoroperations,soyoucanuseitinplaceoflowlevellanguageslikeCandC+.7.Thesefunctionsareintendedtohelpscientistsandengineersvisualizeandunderstandlarge,oftencompl