专业英语词汇1课件

专业英语Keywords:aerial adj.天线的n.天线e.m.wave 电磁波convey vt.传递themorsecode 莫尔斯电码inacontrolledway 有控制的bang n.响声QualityofService服务质量ServiceStatus服务状态Keywords:

FloatType 浮点型（数据）s.s.b=singlesideband 单边带reinsert n.重插入takeplace 发生allowfor 考虑到，允许multiply v.乘，扩大IntersymbolInterference码间干扰

AuxiliaryEquipment辅助设备Keywords:Coverage覆盖CoverageArea覆盖范围,覆盖区,有效区Interference干扰PreliminaryDesign概要设计,初步设计Jam-to-signalratio干扰信号比Interfererdiversity干扰源分集Interference-AdaptiveSystem干扰自适应系统Keywords:感应电荷Inductivecharge高保真度音响HighFidelity高层兼容性HighLayerCompatibility高电位差Highpotentialdifference高频HighFrequency（HF）高增益天线Highgainantenna高增益功放板HighgainPowerAmplifierboard告警面板AlarmpanelKeywords:告警模块Alarmmodule格式转换FormatConversion

隔行扫描InterlaceScanning个人编码PersonalNumber个人识别码PersonalIdentityNumber工程手册EngineeringManual工具软件ToolSoftware个人通信网，专用通信网PersonalCommunicationsNetworkKeywords:规程Procedure规定容限,可接受容限Tolerance规范和描述语言Specification&DescriptionLanguageSDL

规则脉冲激励长期预测RegularPulseExcitedLong-TermPrediction硅钢片SiliconSteelSheet硅谷SiliconValley硅控整流器SiliconControlRectifier

Keywords:骨干网BackboneNetwork固定比特率ConstantBitRate

固定卫星业务FixedSatelliteServices固定信道分配FixedChannelAllocation固态继电器Solid-stateRelay故障,错误fault,error，failure,Bug故障定位Faultlocating故障申告受理FaultComplaintHandlingKeywords:光探测器Photodetector光开关OpticalSwitch光缆FiberOpticCable光连接器FiberConnectors光滤波器OpticalFilters光敏电阻OpticalResistor光耦合器OpticalCouplers光收发模块OpticalTransceiversIfatransmittingaerialradiatesaconstantamplitudee.m.waveitconveyslittleinformationtothereceiver.

transmit 发射，传播aerial 天线radiate 辐射constant 常量，不变的amplitude 振幅e.m.wave=electromagneticwave 电磁波convey 传达receiver 接收者，接收机Thesimplestwayofsendinginformationistoswitchthetransmitteronandoffsothataseriesof'dotsanddashes'aretransmitted--themorsecodeforexample.Thisisaverycommonmethodofcommunicatingbetweenshipsatsea,butitdoesrequiretheoperatorto'read'thecode.switchon(off) 开（关）aseriesof 一连串的morsecode 莫尔斯电码operator 话务员Anyprocessofsuperimposingsomepatternonthecontinuouse.m.wavewhichallowsinformationtobecarriediscalledmodulation.Wesaythecarrierwaveismodulated.Tomodulateacarrierwaveallweneedtodoistovaryapropertyofthewaveinacontrolledway.superimpose 迭加modulation 调制carrierwave 载波property 特性，性质inacontrolledway 有控制地Generally,interference—fromlightingorelectricalmachines--producesamplitudedisturbancesonane.m.wavepassingby.干扰是在光电产品中,伴随着电磁波的传播而产生幅度的干扰Becausetheamplitudeoff.m.carrierisnotcarryinginformation，调频载波幅度并不承载信息suchinterferencehasverylittleeffectonthereceivedsignal.Thisisnotthecasewithana.m.carrier,但是调幅载波就不一样了，whereallsuchbangsandcracklearedetectedatthereceiveras'information'.interference 干扰amplitudedisturbance 振幅波动receivedsignal 接收信号bang 巨响crackle 劈啪响Ontheotherhandthebandwidthofthea.m.carrierismuchlessthanthatofthef.m.carrierasweshallnowshow.下面将给出例子ontheotherhand 另一方面bandwidth 带宽muchless 少得多Ifwemodulatea100kHzcarrierwitha1kHzsignal，itmightbeexpectedthatalthoughthecarrieramplitudewouldmissandfallinstepwiththeamplitudeofthe1kHzsignalthecarrierfrequencywouldremainat100kHz.尽管载波幅度回损失和下降到与…一致,但其频率仍有期望保持在…Infacttwonewfrequencycomponentscanbedetectedinthemodulatedcarrier;theyare101kHzand99kHz.instepwith 与…同步remain 保持component 成分modulatedcarrier 调制波Fig.5.1Thecarrierandsidebandsofana.m.signalbandwidthcarrierLowersiderbanduppersiderband2ffc-fsfcfc+fsThe‘carrier’componentremainsatconstantamplitudeandisnotconveyinginformation(exceptaboutitsownfrequency).载波的成分保持在一个固定的幅度且并不传播信息Itrepresents‘wasted’transmitterpower.Sometimesitisnotradiated没有辐射--thenwehavea‘suppressedcarriera.m.transmission'.抑制Sometimesonlythecarrierandonesidebandareradiated,sometimesonlyonesideband(s.s.b=singles.b.).represent 表明wasted 浪费，消耗suppress 抑制transmission 传输Iflessthanthefulla.m.carrier完全振幅调制载波istransmittedthereceiverneedstobemorecomplicatedtoreceiveit,接收非常复杂becausebasicallythecarriermustbereinsertedatthereceiverbeforedetectioncantakeplace.在检波前要重新再植入一个载波lessthan 小于complicated 复杂的reinsert 重新插入detection 检波Transmittersshouldbespacesapartinfrequencytoallowforthesebandwidthrequirements.Thereareinternationalagreementsaboutfrequenciesbuttheyarenotobservedbyallcountries.transmitter 发射机spaceapart 空间分离allowfor 虑及，考虑到bandwidthrequirement 带宽要求internationalagreement 国际协议observe 遵守Forthemathematicallyinclineditiseasytoshowthatthesinusoidalmodulationoftheamplitudeofasinusoidalwave-formresultsintheproductionofsumanddifferencefrequencies.inclined 倾向sinusoidalmodulation 正弦调制sinusoidalwave-form 正弦波形resultin 导致，体现Supposewehaveanun-modulatedcarrier(fc)oftheforma=Asin(2πfct)whereaistheinstantaneousamplitudeandAisthemaximumamplitude,oftensimplyreferredtoastheamplitudeofthecarrier.NowletusmodulateAsinusoidallyatafrequencyfs,andwrite.suppose 假设un-modulated 未调制instantaneousamplitude 瞬时值maximumamplitude 最大值sinusoidally 正弦地Whenkis1wehave100%modulation,forthetwosidebandseachofamplitudeA/2cancombinetomakethetotalamplitudevaryfromzeroto2A.“for”引导原因状语从句；“Whenkis1”是时间状语从句；“eachofamplitudeA/2”则是后置定语，修饰“sideband”。Inthecaseoff.m.amathematicalanalysisofthemodulatedcarrierismoredifficultthanfora.m.andwouldinvolveusinBesselfunctions.mathematicalanalysis 数学分析modulatedcarrier （已）调制载波Besselfunctions 贝塞尔方程involvein 涉及Besselwasanineteenthcenturymathematicianwhohadtheforesighttosolvetheveryequationsweneedforf.m.Sowecangostraighttotheendofthemathematicalprocessandfindthata