MOOC Optical Fiber Communications-Nanjing University of Posts and Telecommunications 中國大學(xué)慕課答案

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