搜索
1英语复习资料英译汉：electrontube电子管integratedcircuit集成电路voltagedrop电压降Ohm’sLaw欧姆定律electromotiveforce（emf）电动势buildingblock构件（标准组件）directcurrent直流电alternatingcurrent交流电remotevehicles宇宙飞船sourcesupply/powersupply电源negativeterminal负极positiveterminal正极drycell干电池seriescircuits串联电路parallelcircuits并联电路filmtechnique薄膜技术monolithictechnique单片技术operationalamplifier运算放大器blockdiagram方框图relaxationoscillator张弛振荡poweramplifier功率放大器push-pullamplifier推挽放大器changingelectricfield交变电场magneticfields磁场electromagneticwaves电磁场receivingantenna接收天线wirelesstelegraphy无线电报handymultimeter指针式万用表electrongun电子枪controlgrid控制栅（极）electronbeam电子束sinusoidaloscillator正弦波振荡器switchingcircuit开关电路voltagelevel电平rectangularwaveform方波形sawtoothwaveform锯齿形波differentiatedwaveform微分波形alternatingvoltages交变电压magneticinduction磁感应statictransformer静电变压器luminousdischargetube气体放电管primarywinding一次绕组secondarywinding二次绕组audiofrequercies音频ferromagneticpath磁路fluxlines磁力线DolbySurroundSoud杜比环绕声full-bandwidth全带宽digitalaudiocoding数字音频编码DVD-VideoDVD录像带DVD-ROMdiscDVD-ROM光盘laserdisc激光唱盘phosphorscreen荧光屏opticalfiber光钎internetaccess因特网访问（接入）Video-on-Demand视频点播deep-basshandlingsound超低音Centersperker中置音箱surroundspeaker环绕音箱setupprocess设置步骤recordingmedium存储卡recordngmode记录模式imagesize影像尺寸zoomlens变焦镜头zoomring变焦环shutterbutton快门按钮frequencysynthesizer频率合成器hometheater家庭影院DolbyPro-Logicreceiver杜比定向逻辑接收机powerdistributionsystems配电系统alternatingcurrentsystem交变电流系统intelligencetransmission信息传送electromagneticspectrum电磁频谱closed-switchcondition开关闭合状态open-switchcondition开关断开状态cellulartelephone蜂窝式（便携式）电话cordlesstelephoneset无绳电话机half/fullduplex半（全）双工模式theplasmaflatpaneldisplay等离子平板显示器portableAMbroadcastreceivers袖珍调幅广播接收机（收音机）2缩写：AM=amplitudemodulation调幅FM=frequercymodulation调频r-f=radio-frequency射频DTV=DigitalTV数字电视STB=Set-TopBox机顶盒Hi-Fi=High-Fidelity高保真CRT=cathode-raytube阴极射线管LAN=LocalAreaNetwork局域网LCD=liquidcrystaldisplay液晶显示器NIC=NetworkInterfaceCard网卡MAU=MediumAttachmentUnit媒体连接器HDTV=High-DefinitionTV高清晰电视VCR=VideoCassetteRecorder盒式录像机中译英：黑白电视机black-and-whitetelevision调谐负载atunedload硅晶体管silicontransistor负载电阻loadresistor锗晶体管germaniumtransistor负载电流loadcurrent信息时代informationage电压放大器voltageamplifier基本原理thebasicprinciple推挽放大器push-pullamplifier电子元件electroniccomponent功率放大器poweramplifier真空二极管vacuumdiode脉冲放大器pulseamplifier单片singlechip电流放大器currentamplifier面板face-plate电子原理electronicprinciple表笔testprobe/test-leadplug使用手册servicemanual读数reading电信号electricsignal连线：1.fixedresistor6非线性电阻2.theamountofresistance5对电流的电阻力3.electricfield8一个二端原件4.capacityreactance7比例常数5.digitalcircuits2电阻值6.nonlinearresistor1固定电阻7.theconstantofproportionality4容抗8.atwo-terminalelement3电场1.logiccircuits5数字电路2.voltagepulse4方波信号3.theclosed-switchcondition6负脉冲4.square-wavesignal3闭合状态5.Theoppositiontothecurrent1逻辑电路6.thenegativepulse2电压脉冲1.closedcircuitminus4minus2.asamatteroffact7cell3.opencircuit6becomposedof4.negative3acircuitwhichwasbroken5.positive2infact6.consistof1acircuitthatthecurrentcanflowthrough7.battery5plus3GlobalSystemforMobileCommunicaton(GSM)全球移动通信系统Definition(定义)Globalsystemformobilecommunication(GSM)isagloballyacceptedstandardfordigitalcellularcommunication.GSMisthenameofastandardizationgroupestablishedin1982tocreateacommonEuropeanmobiletelephonestandardthatwouldformulatespecificationsforapan-Europeanmobilecellularradiosystemoperatingat900MHz.ItisestimatedthatmanycountriesoutsideofEuropewilljointheGSMpartnership.全球移动通信系统是全球性公认的标准的数字蜂窝通信。GSM标准化组成立于1982创建一个共同欧洲人移动电话标准并制订规范为一个泛欧移动蜂窝式无线设备系统频率在900兆赫。除了欧洲之外还有很多其他的国家也加入了GSM的合伙当中。Overview(概述)ThistutorialprovidesanintroductiontobasicGSMconcepts,specifications,networks,andservices.AshorthistoryofnetworkevolutionisprovidedinordersetthecontextforunderstandingGSM.这个指导书提供介绍了GSM的概念，说明书，网络以及服务的基本内容。并提供一个简短的网络发展史来使其更好地通过其背景来理解GSM。Topics（主题）1.Introduction:TheEvolutionofMobileTelephoneSystems介绍：移动通信系统的发展2.GSM移动通信系统3.TheGSMNetwork移动通信系统的网络4.GSMNetworkAreas移动通信系统的网络服务区域5.GSMSpecifications移动通信系统的说明书6.GSMSubscriberServices移动通信系统的用户服务Self-Test自检CorrectAnswers纠错Glossary术语汇编1.Introduction:TheEvolutionofMobileTelephoneSystems1.介绍：移动通信系统的发展Cellularisoneofthefastestgrowingandmostdemandingtelecommunicationsapplications.Today,itrepresentsacontinuouslyincreasingpercentageofallnewtelephonesubscriptionsaroundtheworld.Currentlytherearemorethan45millioncellularsubscribersworldwide,andnearly50percentofthosesubscribersarelocatedintheUnitedStates.Itisforecastedthatcellularsystemsusingadigitaltechnologywillbecometheuniversalmethodoftelecommunications.Bytheyear2005,forecasterspredictthattherewillbemorethan100millioncellularsubscribersworldwide.Ithasevenbeenestimatedthatsomecountriesmayhavemoremobilephonesthanfixedphonesbytheyear2000(seeFigure1).4蜂窝式的电话是其中一个发展最快和要求最严格的电信应用程序。今天，它代表了全球范围内所有新的手机用户的连续不断的百分百。目前在世界范围内已经有超过4.5亿蜂窝式手机用户，而且接近50%的用户是居住在美国。它预测蜂窝式系统使用数字技术将会变成远程通信普遍的方法。直到2005年，估计有很多国家会出现比2000年的固定电话更多的移动电话（看图1）.Theconceptofcellularserviceistheuseoflow-powertransmitterswherefrequenciescanbereusedwithinageographicarea.Theideaofcell-basedmobileradioservicewasformulatedintheUnitedStatesatBellLabsintheearly1970s.However,theNordiccoun