MOOC Optical Fiber Communications-Nanjing University of Posts and Telecommunications 中国大学慕课答案

MOOCOpticalFiberCommunications-NanjingUniversityofPostsandTelecommunications中国大学慕课答案Exercise1、问题：Forthemeaningsofoptical/lightwavecommunicationsandopticalfibercommunications,whichofthefollowingstatementsisright?选项：A、TheyarecompletelydifferentB、Thecoverageofoptical/lightwavefibercommunicationsislargerthanthatofopticalcommunicationsC、Thecoverageofoptical/lightwavecommunicationsislargerthanthatofopticalfibercommunicationsD、Theyareexactlythesame正确答案:【Thecoverageofoptical/lightwavefibercommunicationsislargerthanthatofopticalcommunications】2、问题：In2009,CharlesKuenKao（K.C.Kao）wonaNobelPrizeforhisgreatcontributioninthetheoryofopticalfibercommunications.InwhichareaistheNobelPrizeKaowon?选项：A、NobelPrizeinMathematicsB、NobelPrizePhysicsC、NobelPrizeinMedicineD、NobelPrizeinChemistry正确答案:【NobelPrizePhysics】3、问题：Inthe1970s,opticalfibercommunicationsfacedimplementationchallenges.Whichoneisthekeytechnicalissue?选项：A、Howtoreducethecostofopticalfibermanufacturing.B、Howtoincreasethesystemtransmissioncapacity.C、Howtocreateatransmissionmediumwithsufficientlylowloss.D、Howtoreducetheenergyconsumptionofopticalfibercommunicationsystem.正确答案:【Howtocreateatransmissionmediumwithsufficientlylowloss.】Exercise1、问题：Whichofthefollowingisthemostpopularfrequencyspectrumusedincommunicationworld?选项：A、InfraredB、UltravioletC、RadioandMicrowaveD、X-ray正确答案:【RadioandMicrowave】2、问题：Ifweadopt1mWasthereferencepowerlevel,howaboutthepowerlevel1Wexpressedindecibelunit?选项：A、1dBmB、10dBmC、30dBmD、1000dBm正确答案:【30dBm】3、问题：WhichspectrumbandoffollowsdoesNOTbelongtoopticalspectrumband?选项：A、O-bandB、C-bandC、L-bandD、X-band正确答案:【X-band】Exercise1、问题：WhichofthefollowingisNOTthecomponentofanopticalfiber?选项：A、coreB、claddingC、bufferD、PEshield正确答案:【PEshield】2、问题：Whichofthefollowingisthemainmaterialofopticalfiber?选项：A、SiO2B、H2OC、NaClD、SiCl4正确答案:【SiO2】3、问题：Whataretherequirementsfortherefractivedifferencebetweencoren1andcladdingn2?选项：A、NonerequirementB、n1mustbebiggerthann2C、n1mustbesmallerthann2D、n1mustequalton2正确答案:【n1mustbebiggerthann2】Exercise1、问题：Whichofthefollowingstatementsaboutfiberstructureisincorrect?选项：A、ThecoreandcladdingareintegratedinstructureB、ThemaindifferencebetweenthecoreandcladdingistherefractiveindexC、ThesizeofthecoreiscomparabletothatofthecladdingD、Therecanbemultiplecoresinthecladding正确答案:【Thesizeofthecoreiscomparabletothatofthecladding】2、问题：Whichoneisthemostimportantthingintheopticalfibermanufacturingprocess?选项：A、PurificationofrawmaterialsB、PreparationofpreformsC、FibercoloringD、Coating正确答案:【Purificationofrawmaterials】3、问题：Whichofthefollowingisnotacommonopticalcablestructure?选项：A、LayertwisttypeB、CenterbeamtubetypeC、HoneycombtypeD、Ribbontype正确答案:【Honeycombtype】Test11、问题：Thecoreandcladdingcannotbephysicallyseparated.选项：A、正确B、错误正确答案:【正确】2、问题：Aftertheopticalfiberismanufactured,itscut-offwavelengthparametercanbedetermined.选项：A、正确B、错误正确答案:【正确】3、问题：Thecoreandcladdingaremadeofpreformedwire.选项：A、正确B、错误正确答案:【正确】Exercise1、问题：WhichofthefollowingdoesNOTbelongtolightparticleproperty?选项：A、TravelsinstraightlinesB、Reflection(changesdirection)C、RefractionD、Polarization正确答案:【Polarization】2、问题：Whenmeetsanobstaclewithverysmallsize,wavecanspillovertheedgeoftheirobstructions.Thisphenomenoniscalled?选项：A、InterferenceB、DiffractionC、PolarizationD、Reflection正确答案:【Diffraction】3、问题：Whobelievedthatthenatureoflightcanbeunderstoodasofstreamsofparticles?选项：A、MaxwellB、HertzC、NewtonD、Young正确答案:【Newton】Exercise1、问题：Alightwavepassesfromalessdensemediumtoadenserone,whatwillhappen?选项：A、TotalreflectionwilldefinitelyoccurB、TotalreflectionmayoccurC、TotalreflectionwillnotoccurD、Itisnotsurewhethertotalreflectionoccurs正确答案:【Totalreflectionwillnotoccur】2、问题：Whatisthepremiseassumptionoftheanalyticalmethodsforthegeometricoptics?选项：A、thewavelengthoflightapproachesinfinityB、thefrequencyoflightapproaches0C、thewavelengthoflightapproaches0D、thelengthoflightapproaches0正确答案:【thewavelengthoflightapproaches0】3、问题：Inordertoensuretheconditionoftotalreflectionattheinterfacebetweenthecoreandthecladding,whatwilltheincidentangleofopticalsignalstofiberendfaceshouldbe?选项：A、ThelargerthebetterB、ThesmallerthebetterC、fixedD、Perpendiculartothefiberaxis正确答案:【Thesmallerthebetter】Exercise1、问题：Whatisthefundamentalmodetransmittedinsingle-modefiber?选项：A、EH11B、HE11C、TE01D、TM11正确答案:【HE11】2、问题：Howtounderstandthephysicalmeaningofthemodesinthefiber?选项：A、ThesolutionofthewaveequationB、ThegeometryofthefibercoreC、TherefractiveindexofthefibermaterialD、Theexistenceorthedistributionofelectromagneticfieldinthefiber正确答案:【Theexistenceorthedistributionofelectromagneticfieldinthefiber】3、问题：Ifamodeexperiencesalmostnoattenuationinthecladding,howtodescribethemode?选项：A、CloseB、RestraintC、ShortcircuitD、Cutoff正确答案:【Cutoff】Test21、问题：Whichofthefollowingstatementsaboutthenumericalaperture(NA)ofanopticalfiberisincorrect?选项：A、Thelargerthenumericalapertureis,thebetterB、Thesmallerthenumericalapertureis,thebetterC、Thevalueisproportionaltotheopticalfiber'sabilityofacceptinglightD、Itreflectsthecouplingabilitybetweenthelightsourceandthefiber正确答案:【Thesmallerthenumericalapertureis,thebetter】2、问题：Whichofthefollowingisthemaincauseofthenonlineareffectofopticalfiber?选项：A、FiberovalityB、InputpoweroftheopticalsignalC、FiberbendingD、Fiberlength正确答案:【Inputpoweroftheopticalsignal】3、问题：WhatisthemainfactorcausingRayleighscattering?选项：A、DefectsequivalenttothewavelengthscaleofthefiberB、DefectsequivalenttothegeometricsizeofthefiberC、DefectsequivalenttothelengthofthefiberD、Impurities正确答案:【Defectsequivalenttothewavelengthscaleofthefiber】Exercise1、问题：Byreducingwhichofthefollowingions,cantheabsorptionattenuationaround1.4μmbeeffectivelyreduced?选项：A、FeB、GeC、OH-D、Si正确答案:【OH-】2、问题：WhichoffollowingNOTbelongstopowerdependentloss?选项：A、SRSB、SBSC、FWMD、BendingLoss正确答案:【BendingLoss】3、问题：Whichofthefollowingbelongstotheintrinsicmaterialabsorption?选项：A、O-HbondabsorptionB、ChromiumionabsorptionC、Ultra-violetabsorptionD、ironionabsorption正确答案:【Ultra-violetabsorption】Exercise1、问题：ThefiberdispersionwillNOTcausewhatkindofeffects?选项：A、TemporalpulsespreadingB、PulseoverlappingC、Intersymbolinterference(ISI)D、Pulseamplitudereduction正确答案:【Pulseamplitudereduction】2、问题：WhichoffollowingdoesNOTbelongtodispersion?选项：A、IntermodaldispersionB、IntramodaldispersionC、PolarizationdispersionD、Refractivedispersion正确答案:【Refractivedispersion】3、问题：Whichofthefollowingisnotthecharacteristicofopticalfibertransmissions?选项：A、LossB、DispersionC、ColorD、Non-lineareffects正确答案:【Color】Exercise1、问题：Whichofthefollowingisthemaincauseofthenonlineareffectofopticalfiber?选项：A、FiberovalityB、InputpoweroftheopticalsignalC、FiberbendingD、Fiberlength正确答案:【Inputpoweroftheopticalsignal】2、问题：WhichofthefollowingdoesNOTbelongtointensity-dependentvariationsintherefractiveindex?选项：A、SRSB、SPMC、XPMD、FWM正确答案:【SRS】3、问题：Whichofthefollowingnonlinearitiesonlyhappeninbackwarddirection?选项：A、SRSB、SBSC、XPMD、FWM正确答案:【SBS】Exercise1、问题：Whichtypeofopticalfiberismostsuitableforhigh-speedmulti-channelsystemsthatoperateatthewavelengthof1.55μm?选项：A、G.652B、G.653C、G.654D、G.655正确答案:【G.655】2、问题：Whichtypeoffibershavetheleastlossatanoperatingwavelengthof1.55μm?选项：A、G.652B、G.653C、G.654D、G.655正确答案:【G.654】3、问题：Whichofthefollowingopticalfiberhassmalllossafterbendingandissuitableforthereceivingsideofendusers?选项：A、G.652fiberB、G.653fiberC、G.655fiberD、G.657fiber正确答案:【G.657fiber】Test31、问题：Themaincauseoftheenergyattenuationofsignaltransmissioninanopticalfiberisthelosscharacteristicsoftheopticalfiber.选项：A、正确B、错误正确答案:【正确】2、问题：Thedispersioninmultimodefiberismainlytheintermodaldispersion.选项：A、正确B、错误正确答案:【正确】3、问题：Theoperatingwavelengthwindowwiththesmallestfibertransmissionlossisnear1.55μm.选项：A、正确B、错误正确答案:【正确】4、问题：Forthesameopticalfiber,thesystemwithhighertransmissionrateismoresensitivetodispersion.选项：A、正确B、错误正确答案:【正确】5、问题：Multi-channelsystemsaremoresusceptibletofibernonlinearitythansingle-channelsystems.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Whenthenumberofparticlesinasubstanceatahighenergylevelisgreaterthanthenumberofparticlesatalowenergylevel,thesubstanceisinstate.选项：A、TotalreflectionB、ParticleabnormaldistributionC、ExcitedabsorptionD、Spontaneousemission正确答案:【Particleabnormaldistribution】2、问题：Regardingtoalaser,theamplificationoflightisachievedthrough.选项：A、OpticalresonatorB、PumplightsourceC、ApplyingdirectcurrentD、ActivatingmaterialwithParticleabnormaldistribution正确答案:【ActivatingmaterialwithParticleabnormaldistribution】3、问题：Theenergylevelstructureofsemiconductormaterialsisnotadiscretesingle-valuedenergylevel,butabandstructurewithacertainwidth,called.选项：A、EnergybandB、ValencebandC、ConductionbandD、Forbiddenband正确答案:【Energyband】Exercises1、问题：ThelightemittedbytheLEDisincoherentlight,anditsbasicprincipleis.选项：A、stimulatedabsorptionB、spontaneousradiationC、stimulatedradiationD、spontaneousradiation正确答案:【spontaneousradiation】2、问题：Whichofthefollowingisrightregardingtothethresholdcurrentofasemiconductorlaser?选项：A、ThebiggerthebetterB、ThesmallerthebetterC、NorequirementD、Noexistenceallowed正确答案:【Thesmallerthebetter】3、问题：Theroleofsemiconductorlasersandlight-emittingdiodesistorealizetheelectro-opticalconversion,whichisessentiallyaPNjunctionwithreversebiasapplied.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Theemissionopticalspectrumofasemiconductorlaservarieswhenworkingconditionschange.Whentheinjectioncurrentislowerthanthethresholdcurrent,itemits.选项：A、LaserwithanarrowspectrallinewidthB、FluorescencewithawidespectrallinewidthC、LaserwithawidespectrallinewidthD、Fluorescencewithanarrowspectrallinewidth正确答案:【Fluorescencewithawidespectrallinewidth】2、问题：Onedisadvantageofsemiconductorlaser(LD)is.选项：A、BroadspectrumB、PoortemperaturecharacteristicsC、LowcouplingefficiencywithfiberD、Lowaverageluminouspower正确答案:【Poortemperaturecharacteristics】3、问题：Whentheoperatingtemperatureofthesemiconductorlaserincreases,itsoutputopticalpowerwill.选项：A、Become0immediatelyB、RemainconstantC、DecreaseD、Increase正确答案:【Decrease】Test41、问题：Thefunctionofthelightsourceisto.选项：A、generateinputlightwavesignalB、convertelectricalsignalcurrentintoopticalsignalpower,inotherwords,realizeelectrical-opticalconversionC、generateinputopticalpowerD、uselightwavesmodulateelectricalsignalssothattheirloadinformationistransmittedinthefiber正确答案:【convertelectricalsignalcurrentintoopticalsignalpower,inotherwords,realizeelectrical-opticalconversion】2、问题：Thekeydevicetorealizeelectric/opticalconversioninopticaltransmitteris.选项：A、LightsourceB、ModulationcircuitC、LightdetectorD、Amplifier正确答案:【Lightsource】3、问题：TheP-IcharacteristicofLEDislinear,sonomatterwhetheritismodulatedbyanalogsignalordigitalsignal,nobiascurrentisrequired.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Themodulation-detectionmethodthatiswidelyusedinopticalfibercommunicationsystemsis.选项：A、Phasemodulation-coherentdetectionB、Intensitymodulation-coherentdetectionC、Frequencymodulation-directdetectionD、Intensitymodulation-directdetection正确答案:【Intensitymodulation-directdetection】2、问题：Therateof5B6Bcoderateincreasesby.选项：A、10%B、20%C、30%D、25%正确答案:【20%】3、问题：Whichofthefollowinglinecodesisnotcommonlyused?选项：A、ScramblingcodeB、mBnBcodeC、InsertioncodeD、NRZcode正确答案:【NRZcode】Exercises1、问题：Toaccuratelycontroltheoutputpowerofthelaser,weshouldproceedfromtwoaspects:oneistocontroltheamplitudeofthemodulatedpulsecurrent;theotheristocontrol.选项：A、micro-semiconductorrefrigeratorB、thephaseofmodulatedpulsecurrentC、thermistorD、biascurrentoflasers正确答案:【biascurrentoflasers】2、问题：Ingeneral,theextinctionratiooftheopticaltransmitterisrequiredtobelessthanorequalto.选项：A、5%B、10%C、15%D、20%正确答案:【10%】3、问题：ThetemperaturecharacteristicsreflecttherelationshipbetweentheLD'sP-Icharacteristicsandtemperature.Whenthetemperatureincreases,thethresholdcurrentincreases.Iftheinjectioncurrentremainsunchangedwhenthetemperatureincreases,theoutputopticalpowerdoesnotchange.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Therequirementsforopticaltransmittersdonotinclude.选项：A、ThelightemittingwavelengthofthelightsourceshouldbesuitableB、VeryhighoutputopticalpowerC、goodextinctionratioD、goodmodulationcharacteristics正确答案:【Veryhighoutputopticalpower】2、问题：Thetransmittedsignalwaveformstipulatesthecharacteristicsoftheopticalpulseshapeofatransmitterintheformofatransmittedeyepatternframe,whichisNotincluded.选项：A、RisingtimeB、FalltimeC、NoiselevelD、Pulseovershoot正确答案:【Noiselevel】3、问题：Whichofthefollowingisnotthemainlimitationofopticaltransmissionsignals.选项：A、eyeopeningB、pulseovershootC、undershootlimitationsD、amplitude正确答案:【amplitude】Test51、问题：Theroleofaddingascramblerbeforethemodulatorofthesystemopticaltransmitteristo.选项：A、GuaranteethetransparencyoftransmissionB、Controltheappearanceoflongstrings1and0C、PerformonlineerrordetectionD、Solvebaselinedrift正确答案:【Controltheappearanceoflongstrings1and0】2、问题：Astheusagetimeofthesemiconductorlaserincreases,itsthresholdcurrentwillbe.选项：A、graduallydecreaseB、remainunchangedC、graduallyincreaseD、graduallyincreasethengraduallydecrease正确答案:【graduallyincrease】3、问题：Thepurposeofscramblingcodeistomakeiteasytotransmitthesignalovertheline.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Thephotodetectorusesmaterial()torealizephotoelectricconversion.选项：A、PhotoelectriceffectB、EnergyC、TimedelayD、Attenuation正确答案:【Photoelectriceffect】2、问题：Thephotodetectorswidelyusedinopticalfibercommunicationsystemsmainlyinclude.选项：A、Laser,light-emittingdiodeB、PINphotodiode,APDavalanchephotodiodeC、Distributedfeedbacklaser,PINphotodiodeD、PINphotodiode,semiconductorlaserLD正确答案:【PINphotodiode,APDavalanchephotodiode】3、问题：Thekeydevicetorealizetheoptical/electricalconversionintheopticalreceiveris.选项：A、LightsourceB、ModulationcircuitC、PhotodetectorD、Amplifier正确答案:【Photodetector】Exercises1、问题：WhichofthefollowingisnotamaincharacteristicofPINphotodiode?选项：A、WavelengthresponsivityB、QuantumefficiencyandspectralcharacteristicsC、ResponsetimeandfrequencycharacteristicsD、noise正确答案:【Wavelengthresponsivity】2、问题：Thequantumefficiencyofavalanchephotodiodesisonlyrelatedtothenumberofprimaryphotocarriers,anddoesnotinvolvethemultiplicationproblem,sothequantumefficiencyisalways选项：A、greaterthan1B、slightlygreaterthan1C、equalto1D、lessthan1正确答案:【lessthan1】3、问题：Quantumefficiencyistheratiooftheaveragenumberofphotoelectronsgeneratedperunittimeataspecificwavelengthtothenumberofincidentphotons.选项：A、正确B、错误正确答案:【正确】Exercises1、问题：Intheopticalreceiver,thenoisesintroducedbytheavalanchephotodiodeinclude选项：A、Darkcurrentnoiseofphotodetector,avalanchemultiplicationnoise,circuitnoiseofopticalreceiverB、Quantumnoise,avalanchemultiplicationnoise,circuitnoiseofopticalreceiverC、DarkcurrentnoiseofphotodetectorandcircuitnoiseofopticalreceiverD、Quantumnoise,darkcurrentnoiseofphotodetector,avalanchemultiplicationnoise正确答案:【Quantumnoise,darkcurrentnoiseofphotodetector,avalanchemultiplicationnoise】2、问题：ThepowersignaltonoiseratioS/Nattheoutputofanopticalreceiverisdefinedby().选项：A、signalpowerfromphotocurrent/(photodetectornoisepower+amplifiernoisepower)B、(photodetectornoisepower+amplifiernoisepower)/signalpowerfromphotocurrentC、signalpowerfromphotocurrent/photodetectornoisepowerD、photodetectornoisepower/signalpowerfromphotocurrent正确答案:【signalpowerfromphotocurrent/(photodetectornoisepower+amplifiernoisepower)】3、问题：Whennolightisincidentonthelight-receivingelementssuchasphotodiodes,thecurrentflowinginthedeviceiscalleddarkcurrent.选项：A、正确B、错误正确答案:【正确】Test61、问题：WhichofthefollowingstatementsrelatingtothebiasvoltageofPINandAPDiscorrect?选项：A、Bothareforward-biasedB、Botharereverse-biasedC、Theformerisforward-biasedandthelatterisreverse-biasedD、Theformerisreverse-biasedandthelatterisforward-biased正确答案:【Botharereverse-biased】2、问题：Thenoiseofthephotodetectorincludesquantumnoise,darkcurrentnoise,leakagecurrentnoiseandmultiplicationnoiseof.选项：A、LightemittingdiodeB、AvalanchephotodiodeC、DoublebasediodeD、Mixingdiode正确答案:【Avalanchephotodiode】3、问题：Whichofthefollowingphysicalquantitydescribestheoptical-to-electricconversionefficiencyofthephotodetector.选项：A、ResponsivityB、SensitivityC、ExtinctionratioD、Gain正确答案:【Responsivity】Exercises1、问题：Atypicalopticalreceiverismainlycomposedof____.选项：A、OpticalreceivingcircuitandoutputinterfacecircuitB、OpticalreceivingcircuitandpreamplifierC、PreamplifierandoutputinterfacecircuitD、Opticalreceivercircuitandequalizationcircuit正确答案:【Opticalreceivingcircuitandoutputinterfacecircuit】2、问题：Thepreamplifiermustmeettherequirementsof____toobtainahighsignal-to-noiseratio.选项：A、LownoiseandhighfrequencyB、LownoiseandhighcapacityC、HighpowerandwidefrequencybandD、Lownoiseandhighgain正确答案:【Lownoiseandhighgain】3、问题：Intheclock(timing)recoverycircuit,baselineprocessingisperformedinorderto____.选项：A、IncreasepowerB、ExtractclockC、ReducenoiseD、Reduceerrorbits正确答案:【Reduceerrorbits】Exercises1、问题：Ifthebiterrorrateofanopticalreceiveris,thentheparameterQisapproximatelyequalto____.选项：A、5B、6C、9D、12正确答案:【6】2、问题：Whichofthefollowingstatementsinvolvingthebiterrorrateofopticalreceptioniscorrect?选项：A、Forsystemswithabiterrorrateof,thereisonly1errorbitforevery1Mbitstransmitted.B、Forsystemswithabiterrorrateof,atleast1errorbitoccursforevery1Mbitstransmitted.C、Forsystemswithabiterrorrateof,thereisanaverageof1errorbitper1Mbitstransmitted.D、Forsystemswithabiterrorrateof,thereisanaverageof1errorbitper1Mbytetransmitted.正确答案:【Forsystemswithabiterrorrateof,thereisanaverageof1errorbitper1Mbitstransmitted.】3、问题：Theerrorrateforopticalfibertelecommunicationsystemsdependsonthesignal-to-noiseratioatthereceiver.选项：A、正确B、错误正确答案:【正确】Exercises1、问题：Whichofthefollowingisthekeyindexofopticalreceiver?选项：A、SensitivityandoverloadpowerB、DynamicrangeandnoiseC、SensitivityanddynamicrangeD、Overloadpowerandsignal-to-noiseratio正确答案:【Sensitivityanddynamicrange】2、问题：Inanidealopticalfibercommunicationsystem,whenthebiterrorratePeisrequiredtobe,theopticalpulsecorrespondingtoeach1codereceivedbytheopticalreceiverincludesatleast____photons.选项：A、21B、27C、121D、126正确答案:【21】3、问题：____characterizestheabilityoftheopticalreceivertoadapttochangesoftheinputsignal.选项：A、SensitivityB、DynamicrangeC、SignaltonoiseratioD、Overloadpower正确答案:【Dynamicrange】Test71、问题：Themainqualityindexoftheopticalreceiverissensitivity,andthemainfactorsthataffectthesensitivityare----____.选项：A、NoiseofopticalreceiverB、StrengthofopticalsignalreceivedbyopticalreceiverC、AmplifiermultiplicationofopticalreceiverD、Noiseofopticalsignal正确答案:【Noiseofopticalreceiver】2、问题：Undertherequirementofguaranteeingthebiterrorrateofthesystem,theminimuminputopticalpowerofthereceiverismeasuredtobe1uW,thenthereceiversensitivityis.选项：A、-10dBmB、-20dBmC、-30dBmD、-40dBm正确答案:【-30dBm】3、问题：Opticalreceiversensitivityreferstotheminimumaverageopticalpowerthattheopticalreceiverneedstoreceive.选项：A、正确B、错误正确答案:【错误】Exercises1、问题：Ifthesourceemittingareaisthecorearea,aminiaturelenscanimprovethepower-couplingefficiency.选项：A、smallerthanB、equaltoC、largerthanD、muchlargerthan正确答案:【smallerthan】2、问题：Whichthefollowingisnotthemechanicalalignmentbetweentwofibers?选项：A、LateraldisplacementB、AngularMisalignmentC、TransverseD、Longitudinal正确答案:【Transverse】3、问题：Considereachfiberhasacorediameterof50μm,ifthetwofibershaveanaxialmisalignmentof5μm,whatistheinsertionlossatthejoint?选项：A、0.590dBB、-0.590dBC、0.873dBD、-0.873dB正确答案:【-0.590dB】Exercises1、问题：isadevicethatcompletesactiveconnectionbetweentwoopticalfibers.选项：A、FiberconnectorB、OpticalfilterC、FiberisolatorD、Fiberattenuator正确答案:【Fiberconnector】2、问题：Accordingto,opticalfibermovableconnectorscanbedividedintotwotypes:aligningtypeandnon-aligningtype.选项：A、ConnectionmethodB、StructureC、OpticalfibermutualcontactrelationshipD、Opticalfibertype正确答案:【Structure】3、问题：Whenusingaconnectorforopticalfiberconnection,iftheconnectorisnotcontinuous,itwillcause.选项：A、OpticalpowercannotbetransmittedB、FresnelreflectionofopticalpowerC、ScatteringlossofopticalpowerD、Partofthescatteringlossofopticalpowerorreturntothetransmittingendintheformofreflection正确答案:【Partofthescatteringlossofopticalpowerorreturntothetransmittingendintheformofreflection】Exercises1、问题：opticalfibercoupleristofusetwoormoreopticalfiberstogetherbyheating.选项：A、FusedconetypeB、PolishedtypeC、Micro-opticalelementtypeD、Integratedopticalwaveguidetype正确答案:【Fusedconetype】2、问题：Whentheopticalfibercommunicationneedstotakeapartofthemaintransmissionchanneloftheopticalfiberfortesting,itneedstouse.选项：A、OpticalattenuatorB、OpticalcouplerC、OpticalisolatorD、Fiberconnector正确答案:【Opticalcoupler】3、问题：Thedevicethatthesemiconductorlaserselectsthefrequencyanddirectionoflightis.选项：A、PumpsourceB、ActivatedsubstanceC、CouplerD、Opticalresonator正确答案:【Opticalresonator】Exercises1、问题：Whichofthefollowingarenotopticalpassivedevices?选项：A、OpticalswitchB、OpticalcouplerC、WavelengthdivisionmultiplexerD、Laser正确答案:【Laser】2、问题：Opticalattenuatorisadevicethatisusedto.选项：A、ChangetheopticalpowerB、ChangetheopticalfrequencyC、ChangethegainD、Changethebandwidth正确答案:【Changetheopticalpower】3、问题：representstheabilityofanopticalisolatortoblockreflectedlight.选项：A、TransmittanceB、ReflectivityC、IsolationD、Shuntratio正确答案:【Isolation】Test81、问题：Whichofthefollowingarenotactivedevices?选项：A、LightsourceB、OpticalamplifierC、PhotodetectorD、Opticalswitch正确答案:【Opticalswitch】2、问题：Theworkingprincipleoftheopticalisolatoris.选项：A、AdjustthepoweroftheopticalsignalB、EnsurethattheopticalsignalcanonlypropagateforwardC、SeparatetheopticalsignalstransmittedinthesamedirectionD、Isolatethemonitoringsignalstransmittedintheopticalfiber正确答案:【Ensurethattheopticalsignalcanonlypropagateforward】3、问题：Theimportantcomponentstoconverttheopticalpathandrealizetheopticalexchangeare.选项：A、opticalswitchB、couplerC、isolatorD、opticalattenuator正确答案:【opticalswitch】Exercises1、问题：Thebasicworkingprincipleofopticalamplifieristhe.选项：A、AvalancheeffectB、PhotoelectriceffectC、StimulatedradiationD、Relaxationoscillation正确答案:【Stimulatedradiation】2、问题：Gainsaturationlimitstheamplifier's.选项：A、DynamicrangeB、WorkingbandwidthC、MagnificationabilityD、Sensitivity正确答案:【Magnificationability】3、问题：Thedegreeofreductionofthesignal-to-noiseratiooftheamplifiedsignalintheopticalamplifierisusuallyexpressedby.选项：A、NoisefigureB、ThermalnoiseC、NoisegainD、Noisemultiplication正确答案:【Noisefigure】Exercises1、问题：Theoperatingwavelengthoftheerbium-dopedfiberamplifierisintherangeof.选项：A、1550nm-1650nmB、980nm-1060nmC、780nm-980nmD、1530nm-1560nm正确答案:【1530nm-1560nm】2、问题：Whichofthefollowingstatementsisincorrect?选项：A、Thepumppowerrequiredtostimulatetheerbium-dopedfiberisrelativelyhighB、ThegainofEDFAishighC、ItiseasytoconnectEDFAtoopticalfiberlinesandthelossislowD、EDFAhaslownoise正确答案:【Thepumppowerrequiredtostimulatetheerbium-dopedfiberisrelativelyhigh】3、问题：Intheco-directionalpumpederbium-dopedfiberamplifier,thetransmissiondirectionsofthepumpinglightandthesignallightare.选项：A、oppositetoeachotherB、thesameC、perpendiculartoeachotherD、Notsure正确答案:【thesame】Exercises1、问题：ThepumpwavelengthcurrentlyusedbyEDFAis.选项：A、0.85μmand1.3μmB、0.85μmand1.48μmC、0.98μmand1.48μmD、0.98μmand1.55μm正确答案:【0.98μmand1.48μm】2、问题：WhichofthefollowingisnottheadvantageofEDFA?选项：A、HighgainB、LargefrequencybandwidthC、SmallnoisefigureD、Abilityofamplifyingmultiplebands正确答案:【Abilityofamplifyingmultiplebands】3、问题：WhichofthefollowingisnottheapplicationofEDFA?选项：A、PoweramplifierB、PreamplifierC、EqualizationamplifierD、Lineamplifier正确答案:【Equalizationamplifier】Exercises1、问题：TheamplificationofopticalsignalsbyfiberRamanamplifiersmainlyutilizestheeffectof.选项：A、RayleighscatteringB、StimulatedBrillouinscatteringC、PockelsD、StimulatedRamanscattering正确答案:【StimulatedRamanscattering】2、问题：WhichofthefollowingisincorrectregardingtotheopticalfiberRamanamplifier?选项：A、RamanamplifiercanbeusedasabroadbandamplifiertoamplifymultipledifferentwavelengthssimultaneouslyB、Ramanamplifiercanbedirectlyusedtoincreasethecapacityoftheoriginalfiber,andthuscanreduceinvestmentC、SpontaneousradiationnoiseoffiberRamanamplifierisbetterthanthatoferbium-dopedfiberamplifierD、FiberRamanamplifiercanonlyamplifysignalsataspecificwavelength正确答案:【FiberRamanamplifiercanonlyamplifysignalsataspecificwavelength】3、问题：ThesaturationpowerandamplificationbandofthefiberRamanamplifieraremainlydeterminedby______.选项：A、PumpinglightB、SignallightC、NoiseD、Fiberlength正确答案:【Pumpinglight】Test91、问题：Thepreamplifierreferstothedevicetightlyconnectedto.选项：A、OpticalresonantcavityB、LaserC、OpticalamplifierD、Photodetector正确答案:【Photodetector】2、问题：TheopticalamplificationprincipleofEDFAis.选项：A、spontaneousradiationB、spontaneousabsorptionC、stimulatedabsorptionD、stimulatedradiation正确答案:【stimulatedradiation】3、问题：Thef