电子信息工程专业英语教程（第5版） 课件 Lesson 11 The mobile telephone system (II)

Unit4ElectronicsystemsLesson11ThemobiletelephoneSystem(II)《电子信息工程专业英语教程（第5版）》Lesson11ThemobiletelephoneSystem(II)

BackgroundsTexttour

LanguageinuseVocabularyStructureReading/writingtechniques2024/5/292《电子信息工程专业英语教程（第5版）》TerminologyTDM时分复用FDM频分复用PCM脉冲编码调制PCS个人通信系统spreadspectrumcommunication

扩频通信Backgrounds2024/5/293《电子信息工程专业英语教程（第5版）》TexttourOutlineD-AMPS-TheDigitalAdvancedMobilePhoneSystemGSM-TheGlobalSystemforMobileCommunicationsCDMA-CodeDivisionMultipleAccess2024/5/294《电子信息工程专业英语教程（第5版）》D-AMPSisthesecondgenerationofAMPSFullydigitalInternationalStandard:IS-54andIS-136D-AMPSandAMPSshare…30kHzchannelupstreamchannelsinthe1850–1910MHzrangedownstreamchannelsinthe1930–1990MHzrange D-AMPSdiffersin…

D-AMPS

TheDigitalAdvancedMobilePhoneSystem2024/5/295《电子信息工程专业英语教程（第5版）》(a)AD-AMPSchannelwith3users.(b)AD-AMPSchannelwith6users.D-AMPS

TheDigitalAdvancedMobilePhoneSystem2024/5/296《电子信息工程专业英语教程（第5版）》GSMissimilartoD-AMPSin…cellularsystemFDMisusedtransmittingononefrequencyandreceivingonahigherfrequencyasinglefrequencypairissplitbyTDMintotimeslotssharedbymultiplemobiles.

GSM

TheGlobalSystemforMobileCommunications2024/5/297《电子信息工程专业英语教程（第5版）》GSMisdifferentfromD-AMPSin…

theGSMchannelsaremuchwider(200kHzvs.30kHz)holdrelativelyfewadditionalusers(3vs.8)GSMhasamuchhigherdatarateperuserGSM

TheGlobalSystemforMobileCommunications2024/5/298《电子信息工程专业英语教程（第5版）》GSMuses124frequencychannels,eachofwhichusesaneight-slotTDMsystem.GSM

TheGlobalSystemforMobileCommunications2024/5/299《电子信息工程专业英语教程（第5版）》AportionoftheGSMframingstructure.GSM

TheGlobalSystemforMobileCommunications2024/5/2910《电子信息工程专业英语教程（第5版）》CompletelydifferentfromD-AMPSandGSMAnanalogyFDMAis…TDMAis…CDMAis…

AnexamplePracticalconsiderationsforCDMACDMA

CodeDivisionMultipleAccess2024/5/2911《电子信息工程专业英语教程（第5版）》Vocabularymodulation,approximation,conflict,comparable,random,complement,inverse,spectrum,parallel,scheme,complicateStructureReading/writingtechniquesLanguageinuse2024/5/2912《电子信息工程专业英语教程（第5版）》Vocabulary2024/5/2913《电子信息工程专业英语教程（第5版）》ModulationindictionaryAchangeinstress,pitch,loudness,ortoneofthevoice;aninflectionofthevoice.Thevariationofapropertyofanelectromagneticwaveorsignal,suchasitsamplitude,frequency,orphase.Theprocessbywhichsomecharacteristicofonewaveisvariedinaccordancewithanotherwaveorsignal.Thistechniqueisusedinmodemstomakebusinessmachinesignalscompatiblewithcommunicationfacilities.Amethodofrepresentingdatainmagnetizablesurfacestorage;forexample,“modifiedfrequencymodulation”.2024/5/2914《电子信息工程专业英语教程（第5版）》ModulationintextOnaD-AMPSmobilephone,thevoicesignalpickedupbythemicrophoneisdigitizedandcompressedusingamodelthatismoresophisticatedthanthedeltamodulationandpredictiveencodingschemes.在D-AMPS移动电话上，语音信号由麦克风拾取之后，先进行数字化，然后使用比增量调制和预测编码更复杂的模型进行压缩。

2024/5/2915《电子信息工程专业英语教程（第5版）》Modulationinuse

adaptivedeltamodulation自适应增量调制amplitudemodulation调幅anglemodulation角调制(调频与调相)binarypulse-codemodulation二进制脉(冲编)码调制differentialpulsecodemodulation差值脉冲编码调制2024/5/2916《电子信息工程专业英语教程（第5版）》Modulationinuse

differentialpulsecodemodulation差分脉冲编码调制directfrequencymodulation直接调频displacementmodulation(脉冲)相位[位移]调制double-sidebandmodulation双边带调制2024/5/2917《电子信息工程专业英语教程（第5版）》Modulationinuse

incidentalphasemodulation寄生调相pulse-amplitudemodulation脉幅调制quadraturemodulation正交调制,直角相位调制vestigialsidebandmodulation残留边带调制2024/5/2918《电子信息工程专业英语教程（第5版）》ApproximationindictionaryTheact,process,orresultofapproximating.

接近Aninexactresultadequateforagivenpurpose.

近似值2024/5/2919《电子信息工程专业英语教程（第5版）》ApproximationintextToafirst

approximation,GSMissimilartoD-AMPS.Botharecellularsystems.乍一看，GSM和D-AMPS很相似。两者都是蜂窝系统。2024/5/2920《电子信息工程专业英语教程（第5版）》Approximationinuse

bestpolynomialapproximation最佳多项式逼近closestrationalapproximation最近分数,最近有理近似法differenceapproximation差分近似differentialapproximation微分逼近digitalapproximation数值逼近engineeringapproximation工程近似法exponentialapproximation指数近似2024/5/2921《电子信息工程专业英语教程（第5版）》Approximationinuse

finite-differenceapproximation有限差分近似leastsquareapproximation最小二乘逼近linearapproximation线性近似,线性逼近lumpedparameterapproximation集中参数近似rationalfunctionapproximation有理函数逼近2024/5/2922《电子信息工程专业英语教程（第5版）》MultiplexindictionaryRelatingto,having,orconsistingofmultipleelementsorparts:

复合的Relatingtoorbeingasystemofsimultaneouscommunicationoftwoormoremessages

onthesamewireorradiochannel.

多路传输的Abuilding,especiallyamovietheaterordwelling,withmultipleseparateunits.

复合式建筑Tosendmessagesorsignals

simultaneouslyusingamultiplexsystem.

多路传输Tosendsimultaneouslyusingamultiplexsystem.

多路传输2024/5/2923《电子信息工程专业英语教程（第5版）》MultiplexintextWithmobiletelephonythereisahugegainfromdoingdigitizationandcompressioninthehandset,somuchsothatinD-AMPS,threeuserscanshareasinglefrequencypairusingtimedivisionmultiplexing.

对于移动电话而言，在电话机内完成数字化并进行数据压缩有很大好处——这样一来，3个D-AMPS用户可以通过时分复用共用一对频率。

2024/5/2924《电子信息工程专业英语教程（第5版）》Multiplexinuse

code-divisionmultiplex码分多路通信frequencymultiplex频率多工通信frequency-divisionmultiplex频分多路复用spacedivisionmultiplex空分多路通信stereomultiplex立体声多路传输2024/5/2925《电子信息工程专业英语教程（第5版）》Multiplexinuse

Simplex

单工通信Atermappliedtoacircuitormethodofworkinginwhichdataistransmittedinonlyonepre-assigneddirection.Duplex

双工通信(fullduplex,halfduplex)Indatacommunication,pertainingtoasimultaneoustwo-wayindependenttransmission

inbothdirections.Complex2024/5/2926《电子信息工程专业英语教程（第5版）》ConflictindictionaryAstateofopen,oftenprolongedfighting;abattleorwar.

战役或战争Astateofdisharmonybetweenincompatibleorantitheticalpersons,ideas,orinterests;aclash.

冲突

Apsychicstruggle,oftenunconscious,resultingfromtheoppositionorsimultaneousfunctioningofmutuallyexclusiveimpulses,desires,ortendencies.

心理挣扎Oppositionbetweencharactersorforcesinaworkofdramaorfiction,especiallyoppositionthatmotivatesorshapestheactionoftheplot.

（戏剧或小说）冲突2024/5/2927《电子信息工程专业英语教程（第5版）》ConflictintextTheoretically,992channelscanbesupportedineachcell,butmanyofthemarenotavailable,toavoidfrequencyconflictswithneighboringcells.理论上讲，每个蜂窝小区可以支持992个信道；但为了避免和邻近蜂窝小区发生频率冲突，许多信道并不能使用。

2024/5/2928《电子信息工程专业英语教程（第5版）》Conflictinuse

conflictcontestcombatfightaffray Thesenounsdenotestrugglebetweenopposingforcesforvictoryorsupremacy.

Conflictappliesbothtoopenfightingbetweenhostilegroupsandtoastruggle,oftenaninnerstruggle,betweenantitheticalforcesContestcanrefereithertofriendlycompetitionortoahostilestruggletoachieveanobjective:anarcherycontest;aspellingcontest;2024/5/2929《电子信息工程专业英语教程（第5版）》Conflictinuse

conflictcontestcombatfightaffrayCombatmostcommonlyimpliesanencounterbetweentwoarmedpersonsorgroups:Fightusuallyreferstoaclash,physicalorfigurative,involvingindividualadversaries:Afightwasscheduledbetweentheworldboxingchampionandthechallenger.

Affraysuggestsapublicfightorbrawl:2024/5/2930《电子信息工程专业英语教程（第5版）》ComparableindictionaryAdmittingofcomparisonwithanotherorothers:

可比较的Ourhouseisnotcomparablewithyours.Afireiscomparablewiththesun;bothgivelightandheat.Similarorequivalent:

相似或相当：AcomparablecarwouldcostfarmoreinEurope.Nohorsehasaspeedcomparabletothatofhis.2024/5/2931《电子信息工程专业英语教程（第5版）》ComparableintextTDMiscomparable

tothepeoplebeinginthemiddleoftheroombuttakingturnsspeaking.FDMiscomparabletothepeoplebeinginwidelyseparatedclumps,eachclumpholdingitsownconversationatthesametimeas,butstillindependentof,theothers.CDMAiscomparabletoeverybodybeinginthemiddleoftheroomtalkingatonce,butwitheachpairinadifferentlanguage.2024/5/2932《电子信息工程专业英语教程（第5版）》RandomindictionaryHavingnospecificpattern,purpose,orobjective:

没有明确形式、目的或内容的：randommovements;arandomchoice.Oforrelatingtothesameorequalchancesorprobabilityofoccurrenceforeachmemberofagroup.

随机的2024/5/2933《电子信息工程专业英语教程（第5版）》RandomintextThus,thekeytoCDMAistobeabletoextractthedesiredsignalwhilerejectingeverythingelseas

randomnoise.因此，CDMA的关键在于能够提取出希望得到的信号，而把其他信号当作随机噪声而加以抑制。2024/5/2934《电子信息工程专业英语教程（第5版）》Randominuse

random,haphazard,chance,casualRandom强调某事不是按计划发生的Theexperimentcannotbesatisfactorybecausehehastousetherandomselectionofspecimens.Haphazard表示说话或使用某物时不考虑效果Heregrertedhishaphazardremarks.Chance包含着冒险性或不确定性，或者结果是不能预知的Withoutsomethingofthiskind,searchingforintelligenceonotherplanetswouldbeliketryingtomeetafriendinLondonwithoutapre-arrangedrendezvousandabsurdlywanderingthestreetsinthehopeofachanceencounter.Casual表示“随便的”2024/5/2935《电子信息工程专业英语教程（第5版）》ComplementindictionarySomethingthatcompletes,makesupawhole,orbringstoperfection.

补充物Thequantityornumberneededtomakeupawhole:

补足Eitheroftwopartsthatcompletethewholeormutuallycompleteeachother.

补数Ananglerelatedtoanothersothatthesumoftheirmeasuresis90.

余角2024/5/2936《电子信息工程专业英语教程（第5版）》ComplementintextEachstationisassignedauniquem-bitcodecalledachipsequence.Totransmita1bit,astationsendsitschipsequence.Totransmita0bit,itsendstheone’scomplementofitschipsequence.每个（移动）站分配到唯一的一个称为“码片序列”的m位码。要传送比特“1”，就发送这个码片序列；要传送比特“0”，就发送这个码片序列的反码。

2024/5/2937《电子信息工程专业英语教程（第5版）》Complementinuse

One’scomplement二进制反码two’scomplement二进制补码complementofanangle余角complementofanumber余数complementofaset补集2024/5/2938《电子信息工程专业英语教程（第5版）》Complementinuse

Complementcompliment

Complementandcompliment,thoughquitedistinctinmeaning,aresometimesconfusedbecausetheyarepronouncedthesame.

Complementmeanssomethingthatcompletesorbringstoperfection.Theantiquesilverwasacomplementtothebeautifullysettable.Complimentmeansanexpressionoractofcourtesyorpraise.Theygaveusacomplimentonourbeautifullysettable.2024/5/2939《电子信息工程专业英语教程（第5版）》InverseindictionaryReversedinorder,nature,oreffect.

相反的Oforrelatingtoaninverseoraninversefunction.

相反的

Turnedupsidedown;inverted.

颠倒的；倒置的2024/5/2940《电子信息工程专业英语教程（第5版）》InverseindictionaryThereciprocalofadesignatedquantity.

Alsocalled:multiplicativeinverse

倒数Thenegativeofadesignatedquantity.

Alsocalled:additiveinverse

相反数2024/5/2941《电子信息工程专业英语教程（第5版）》InverseintextAgoodheuristichereisforeachmobilestationtotransmittothebasestationattheinverse

ofthepowerlevelitreceivesfromthebasestation.一个很好的思路是：每个移动站向基站发送信号的功率是接收到的基站信号功率电平的倒数。

2024/5/2942《电子信息工程专业英语教程（第5版）》Inverseinuse

ReverseTransverse2024/5/2943《电子信息工程专业英语教程（第5版）》SpectrumindictionaryThedistributionofenergy

emittedbyaradiantsource,asbyanincandescentbody,arrangedinorderofwavelengths.

光谱Thedistributionofatomicorsubatomicparticlesinasystem,asinamagneticallyresolvedmolecularbeam,arrangedinorderofmasses.

能谱Agraphicorphotographicrepresentationofsuchadistribution.

谱图2024/5/2944《电子信息工程专业英语教程（第5版）》SpectrumindictionaryArangeofvaluesofaquantityorsetofrelatedquantities.

范围Abroadsequenceorrangeofrelatedqualities,ideas,oractivities:

系列，范围thewholespectrumof20th-centurythought.thewholespectrumofindustry2024/5/2945《电子信息工程专业英语教程（第5版）》SpectrumintextIncreasingtheamountofinformationtobesentfrombbits/sectombchips/seccanonlybedoneifthebandwidthavailableisincreasedbyafactorofm,makingCDMAaformofspreadspectrumcommunication(assumingnochangesinthemodulationorencodingtechniques).只要可用带宽提高至原来的m倍，就可以将发送信息量从b位/秒提高到mb码片/秒；这使得CDMA是一种扩频通信的形式（假定调制和编码技术没有发生变化的话）。

2024/5/2946《电子信息工程专业英语教程（第5版）》Spectruminuseabsorptionspectrum吸收光谱,吸收频谱electromagneticspectrum电磁波频谱energydensityspectrum能量密度谱frequencyspectrum频谱infraredspectrum红外线谱phasespectrum相位谱powerspectrum能谱,功率谱powerdensityspectrum功率密度谱uppersidebandspectrum上边带谱2024/5/2947《电子信息工程专业英语教程（第5版）》ParallelindictionaryBeinganequaldistanceaparteverywhere平行的Havingcomparableparts,analogousaspects,orreadilyrecognizedsimilarities相似的，相同的，对等的theparallellivesoftwocontemporaries.Havingthesametendencyordirection

具有相同倾向的parallelmotivesandaims.Denotingacircuitorpartofacircuitconnectedinparallel.并联的Oforrelatingtothesimultaneoustransmissionofallthebitsofabyteoverseparatewires同时输送的Oforrelatingtothesimultaneousperformanceofmultipleoperations并行的parallelprocessing.2024/5/2948《电子信息工程专业英语教程（第5版）》ParallelindictionaryOneofasetofparallelgeometricfigures,suchaslinesorplanes.平行线，平行面Onethatcloselyresemblesorisanalogoustoanother相似物Acomparisonindicatinglikeness;ananalogy.类比Theconditionofbeingparallel;nearsimilarityorexactagreementinparticulars;parallelism.类似Anyoftheimaginarylinesrepresentingdegreesoflatitudethatencircletheearthparalleltotheplaneoftheequator.纬线Anarrangementofcomponentsinacircuitthatsplitsthecurrentintotwoormorepaths.Usedchieflyinthephraseinparallel.

并联2024/5/2949《电子信息工程专业英语教程（第5版）》ParallelintextInprinciple,givenenoughcomputingcapacity,thereceivercanlistentoallthesendersatoncebyrunningthedecodingalgorithmforeachoftheminparallel.从理论上讲，假如具备足够的计算能力，通过并行运行解码算法，接收机就能同时听到每一个发送方。

2024/5/2950《电子信息工程专业英语教程（第5版）》SchemeindictionaryAsystematicplanofaction.

系统性计划Asecretordeviousplan;aplot.

阴谋；计划Animpracticalorunrealisticplan:

不切实际的计划Anorde