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

【MOOC】OpticalFiberCommunications-NanjingUniversityofPostsandTelecommunications中国大学慕课MOOC答案Exercise1、【单选题】Forthemeaningsofoptical/lightwavecommunicationsandopticalfibercommunications,whichofthefollowingstatementsisright?本题答案：【Thecoverageofoptical/lightwavefibercommunicationsislargerthanthatofopticalcommunications】2、【单选题】In2009,CharlesKuenKao（K.C.Kao）wonaNobelPrizeforhisgreatcontributioninthetheoryofopticalfibercommunications.InwhichareaistheNobelPrizeKaowon?本题答案：【NobelPrizePhysics】3、【单选题】Inthe1970s,opticalfibercommunicationsfacedimplementationchallenges.Whichoneisthekeytechnicalissue?本题答案：【Howtocreateatransmissionmediumwithsufficientlylowloss.】Exercise1、【单选题】Whichofthefollowingisthemostpopularfrequencyspectrumusedincommunicationworld?本题答案：【RadioandMicrowave】2、【单选题】Ifweadopt1mWasthereferencepowerlevel,howaboutthepowerlevel1Wexpressedindecibelunit?本题答案：【30dBm】3、【单选题】WhichspectrumbandoffollowsdoesNOTbelongtoopticalspectrumband?本题答案：【X-band】Exercise1、【单选题】WhichofthefollowingisNOTthecomponentofanopticalfiber?本题答案：【PEshield】2、【单选题】Whichofthefollowingisthemainmaterialofopticalfiber?本题答案：【SiO2】3、【单选题】Whataretherequirementsfortherefractivedifferencebetweencoren1andcladdingn2?本题答案：【n1mustbebiggerthann2】Exercise1、【单选题】Whichofthefollowingstatementsaboutfiberstructureisincorrect?本题答案：【Thesizeofthecoreiscomparabletothatofthecladding】2、【单选题】Whichoneisthemostimportantthingintheopticalfibermanufacturingprocess?本题答案：【Purificationofrawmaterials】3、【单选题】Whichofthefollowingisnotacommonopticalcablestructure?本题答案：【Honeycombtype】Test11、【判断题】Thecoreandcladdingcannotbephysicallyseparated.本题答案：【正确】2、【判断题】Aftertheopticalfiberismanufactured,itscut-offwavelengthparametercanbedetermined.本题答案：【正确】3、【判断题】Thecoreandcladdingaremadeofpreformedwire.本题答案：【正确】Exercise1、【单选题】WhichofthefollowingdoesNOTbelongtolightparticleproperty?本题答案：【Polarization】2、【单选题】Whenmeetsanobstaclewithverysmallsize,wavecanspillovertheedgeoftheirobstructions.Thisphenomenoniscalled?本题答案：【Diffraction】3、【单选题】Whobelievedthatthenatureoflightcanbeunderstoodasofstreamsofparticles?本题答案：【Newton】Exercise1、【单选题】Alightwavepassesfromalessdensemediumtoadenserone,whatwillhappen?本题答案：【Totalreflectionwillnotoccur】2、【单选题】Whatisthepremiseassumptionoftheanalyticalmethodsforthegeometricoptics?本题答案：【thewavelengthoflightapproaches0】3、【单选题】Inordertoensuretheconditionoftotalreflectionattheinterfacebetweenthecoreandthecladding,whatwilltheincidentangleofopticalsignalstofiberendfaceshouldbe?本题答案：【Thesmallerthebetter】Exercise1、【单选题】Whatisthefundamentalmodetransmittedinsingle-modefiber?本题答案：【HE11】2、【单选题】Howtounderstandthephysicalmeaningofthemodesinthefiber?本题答案：【Theexistenceorthedistributionofelectromagneticfieldinthefiber】3、【单选题】Ifamodeexperiencesalmostnoattenuationinthecladding,howtodescribethemode?本题答案：【Cutoff】Test21、【单选题】Whichofthefollowingstatementsaboutthenumericalaperture(NA)ofanopticalfiberisincorrect?本题答案：【Thesmallerthenumericalapertureis,thebetter】2、【单选题】Whichofthefollowingisthemaincauseofthenonlineareffectofopticalfiber?本题答案：【Inputpoweroftheopticalsignal】3、【单选题】WhatisthemainfactorcausingRayleighscattering?本题答案：【Defectsequivalenttothewavelengthscaleofthefiber】Exercise1、【单选题】Byreducingwhichofthefollowingions,cantheabsorptionattenuationaround1.4μmbeeffectivelyreduced?本题答案：【OH-】2、【单选题】WhichoffollowingNOTbelongstopowerdependentloss?本题答案：【BendingLoss】3、【单选题】Whichofthefollowingbelongstotheintrinsicmaterialabsorption?本题答案：【Ultra-violetabsorption】Exercise1、【单选题】ThefiberdispersionwillNOTcausewhatkindofeffects?本题答案：【Pulseamplitudereduction】2、【单选题】WhichoffollowingdoesNOTbelongtodispersion?本题答案：【Refractivedispersion】3、【单选题】Whichofthefollowingisnotthecharacteristicofopticalfibertransmissions?本题答案：【Color】Exercise1、【单选题】Whichofthefollowingisthemaincauseofthenonlineareffectofopticalfiber?本题答案：【Inputpoweroftheopticalsignal】2、【单选题】WhichofthefollowingdoesNOTbelongtointensity-dependentvariationsintherefractiveindex?本题答案：【SRS】3、【单选题】Whichofthefollowingnonlinearitiesonlyhappeninbackwarddirection?本题答案：【SBS】Exercise1、【单选题】Whichtypeofopticalfiberismostsuitableforhigh-speedmulti-channelsystemsthatoperateatthewavelengthof1.55μm?本题答案：【G.655】2、【单选题】Whichtypeoffibershavetheleastlossatanoperatingwavelengthof1.55μm?本题答案：【G.654】3、【单选题】Whichofthefollowingopticalfiberhassmalllossafterbendingandissuitableforthereceivingsideofendusers?本题答案：【G.657fiber】Test31、【判断题】Themaincauseoftheenergyattenuationofsignaltransmissioninanopticalfiberisthelosscharacteristicsoftheopticalfiber.本题答案：【正确】2、【判断题】Thedispersioninmultimodefiberismainlytheintermodaldispersion.本题答案：【正确】3、【判断题】Theoperatingwavelengthwindowwiththesmallestfibertransmissionlossisnear1.55μm.本题答案：【正确】4、【判断题】Forthesameopticalfiber,thesystemwithhighertransmissionrateismoresensitivetodispersion.本题答案：【正确】5、【判断题】Multi-channelsystemsaremoresusceptibletofibernonlinearitythansingle-channelsystems.本题答案：【错误】Exercises1、【单选题】Whenthenumberofparticlesinasubstanceatahighenergylevelisgreaterthanthenumberofparticlesatalowenergylevel,thesubstanceisinstate.本题答案：【Particleabnormaldistribution】2、【单选题】Regardingtoalaser,theamplificationoflightisachievedthrough.本题答案：【ActivatingmaterialwithParticleabnormaldistribution】3、【单选题】Theenergylevelstructureofsemiconductormaterialsisnotadiscretesingle-valuedenergylevel,butabandstructurewithacertainwidth,called.本题答案：【Energyband】Exercises1、【单选题】ThelightemittedbytheLEDisincoherentlight,anditsbasicprincipleis.本题答案：【spontaneousradiation】2、【单选题】Whichofthefollowingisrightregardingtothethresholdcurrentofasemiconductorlaser?本题答案：【Thesmallerthebetter】3、【判断题】Theroleofsemiconductorlasersandlight-emittingdiodesistorealizetheelectro-opticalconversion,whichisessentiallyaPNjunctionwithreversebiasapplied.本题答案：【错误】Exercises1、【单选题】Theemissionopticalspectrumofasemiconductorlaservarieswhenworkingconditionschange.Whentheinjectioncurrentislowerthanthethresholdcurrent,itemits.本题答案：【Fluorescencewithawidespectrallinewidth】2、【单选题】Onedisadvantageofsemiconductorlaser(LD)is.本题答案：【Poortemperaturecharacteristics】3、【单选题】Whentheoperatingtemperatureofthesemiconductorlaserincreases,itsoutputopticalpowerwill.本题答案：【Decrease】Test41、【单选题】Thefunctionofthelightsourceisto.本题答案：【convertelectricalsignalcurrentintoopticalsignalpower,inotherwords,realizeelectrical-opticalconversion】2、【单选题】Thekeydevicetorealizeelectric/opticalconversioninopticaltransmitteris.本题答案：【Lightsource】3、【判断题】TheP-IcharacteristicofLEDislinear,sonomatterwhetheritismodulatedbyanalogsignalordigitalsignal,nobiascurrentisrequired.本题答案：【错误】Exercises1、【单选题】Themodulation-detectionmethodthatiswidelyusedinopticalfibercommunicationsystemsis.本题答案：【Intensitymodulation-directdetection】2、【单选题】Therateof5B6Bcoderateincreasesby.本题答案：【20%】3、【单选题】Whichofthefollowinglinecodesisnotcommonlyused?本题答案：【NRZcode】Exercises1、【单选题】Toaccuratelycontroltheoutputpowerofthelaser,weshouldproceedfromtwoaspects:oneistocontroltheamplitudeofthemodulatedpulsecurrent;theotheristocontrol.本题答案：【biascurrentoflasers】2、【单选题】Ingeneral,theextinctionratiooftheopticaltransmitterisrequiredtobelessthanorequalto.本题答案：【10%】3、【判断题】ThetemperaturecharacteristicsreflecttherelationshipbetweentheLD'sP-Icharacteristicsandtemperature.Whenthetemperatureincreases,thethresholdcurrentincreases.Iftheinjectioncurrentremainsunchangedwhenthetemperatureincreases,theoutputopticalpowerdoesnotchange.本题答案：【错误】Exercises1、【单选题】Therequirementsforopticaltransmittersdonotinclude.本题答案：【Veryhighoutputopticalpower】2、【单选题】Thetransmittedsignalwaveformstipulatesthecharacteristicsoftheopticalpulseshapeofatransmitterintheformofatransmittedeyepatternframe,whichisNotincluded.本题答案：【Noiselevel】3、【单选题】Whichofthefollowingisnotthemainlimitationofopticaltransmissionsignals.本题答案：【amplitude】Test51、【单选题】Theroleofaddingascramblerbeforethemodulatorofthesystemopticaltransmitteristo.本题答案：【Controltheappearanceoflongstrings1and0】2、【单选题】Astheusagetimeofthesemiconductorlaserincreases,itsthresholdcurrentwillbe.本题答案：【graduallyincrease】3、【判断题】Thepurposeofscramblingcodeistomakeiteasytotransmitthesignalovertheline.本题答案：【错误】Exercises1、【单选题】Thephotodetectorusesmaterial()torealizephotoelectricconversion.本题答案：【Photoelectriceffect】2、【单选题】Thephotodetectorswidelyusedinopticalfibercommunicationsystemsmainlyinclude.本题答案：【PINphotodiode,APDavalanchephotodiode】3、【单选题】Thekeydevicetorealizetheoptical/electricalconversionintheopticalreceiveris.本题答案：【Photodetector】Exercises1、【单选题】WhichofthefollowingisnotamaincharacteristicofPINphotodiode?本题答案：【Wavelengthresponsivity】2、【单选题】Thequantumefficiencyofavalanchephotodiodesisonlyrelatedtothenumberofprimaryphotocarriers,anddoesnotinvolvethemultiplicationproblem,sothequantumefficiencyisalways本题答案：【lessthan1】3、【判断题】Quantumefficiencyistheratiooftheaveragenumberofphotoelectronsgeneratedperunittimeataspecificwavelengthtothenumberofincidentphotons.本题答案：【正确】Exercises1、【单选题】Intheopticalreceiver,thenoisesintroducedbytheavalanchephotodiodeinclude本题答案：【Quantumnoise,darkcurrentnoiseofphotodetector,avalanchemultiplicationnoise】2、【单选题】ThepowersignaltonoiseratioS/Nattheoutputofanopticalreceiverisdefinedby().本题答案：【signalpowerfromphotocurrent/(photodetectornoisepower+amplifiernoisepower)】3、【判断题】Whennolightisincidentonthelight-receivingelementssuchasphotodiodes,thecurrentflowinginthedeviceiscalleddarkcurrent.本题答案：【正确】Test61、【单选题】WhichofthefollowingstatementsrelatingtothebiasvoltageofPINandAPDiscorrect?本题答案：【Botharereverse-biased】2、【单选题】Thenoiseofthephotodetectorincludesquantumnoise,darkcurrentnoise,leakagecurrentnoiseandmultiplicationnoiseof.本题答案：【Avalanchephotodiode】3、【单选题】Whichofthefollowingphysicalquantitydescribestheoptical-to-electricconversionefficiencyofthephotodetector.本题答案：【Responsivity】Exercises1、【单选题】Atypicalopticalreceiverismainlycomposedof____.本题答案：【Opticalreceivingcircuitandoutputinterfacecircuit】2、【单选题】Thepreamplifiermustmeettherequirementsof____toobtainahighsignal-to-noiseratio.本题答案：【Lownoiseandhighgain】3、【单选题】Intheclock(timing)recoverycircuit,baselineprocessingisperformedinorderto____.本题答案：【Reduceerrorbits】Exercises1、【单选题】Ifthebiterrorrateofanopticalreceiveris,thentheparameterQisapproximatelyequalto____.本题答案：【6】2、【单选题】Whichofthefollowingstatementsinvolvingthebiterrorrateofopticalreceptioniscorrect?本题答案：【Forsystemswithabiterrorrateof,thereisanaverageof1errorbitper1Mbitstransmitted.】3、【判断题】Theerrorrateforopticalfibertelecommunicationsystemsdependsonthesignal-to-noiseratioatthereceiver.本题答案：【正确】Exercises1、【单选题】Whichofthefollowingisthekeyindexofopticalreceiver?本题答案：【Sensitivityanddynamicrange】2、【单选题】Inanidealopticalfibercommunicationsystem,whenthebiterrorratePeisrequiredtobe,theopticalpulsecorrespondingtoeach1codereceivedbytheopticalreceiverincludesatleast____photons.本题答案：【21】3、【单选题】____characterizestheabilityoftheopticalreceivertoadapttochangesoftheinputsignal.本题答案：【Dynamicrange】Test71、【单选题】Themainqualityindexoftheopticalreceiverissensitivity,andthemainfactorsthataffectthesensitivityare----____.本题答案：【Noiseofopticalreceiver】2、【单选题】Undertherequirementofguaranteeingthebiterrorrateofthesystem,theminimuminputopticalpowerofthereceiverismeasuredtobe1uW,thenthereceiversensitivityis.本题答案：【-30dBm】3、【判断题】Opticalreceiversensitivityreferstotheminimumaverageopticalpowerthattheopticalreceiverneedstoreceive.本题答案：【错误】Exercises1、【单选题】Ifthesourceemittingareaisthecorearea,aminiaturelenscanimprovethepower-couplingefficiency.本题答案：【smallerthan】2、【单选题】Whichthefollowingisnotthemechanicalalignmentbetweentwofibers?本题答案：【Transverse】3、【单选题】Considereachfiberhasacorediameterof50μm,ifthetwofibershaveanaxialmisalignmentof5μm,whatistheinsertionlossatthejoint?本题答案：【-0.590dB】Exercises1、【单选题】isadevicethatcompletesactiveconnectionbetweentwoopticalfibers.本题答案：【Fiberconnector】2、【单选题】Accordingto,opticalfibermovableconnectorscanbedividedintotwotypes:aligningtypeandnon-aligningtype.本题答案：【Structure】3、【单选题】Whenusingaconnectorforopticalfiberconnection,iftheconnectorisnotcontinuous,itwillcause.本题答案：【Partofthescatteringlossofopticalpowerorreturntothetransmittingendintheformofreflection】Exercises1、【单选题】opticalfibercoupleristofusetwoormoreopticalfiberstogetherbyheating.本题答案：【Fusedconetype】2、【单选题】Whentheopticalfibercommunicationneedstotakeapartofthemaintransmissionchanneloftheopticalfiberfortesting,itneedstouse.本题答案：【Opticalcoupler】3、【单选题】Thedevicethatthesemiconductorlaserselectsthefrequencyanddirectionoflightis.本题答案：【Opticalresonator】Exercises1、【单选题】Whichofthefollowingarenotopticalpassivedevices?本题答案：【Laser】2、【单选题】Opticalattenuatorisadevicethatisusedto.本题答案：【Changetheopticalpower】3、【单选题】representstheabilityofanopticalisolatortoblockreflectedlight.本题答案：【Isolation】Test81、【单选题】Whichofthefollowingarenotactivedevices?本题答案：【Opticalswitch】2、【单选题】Theworkingprincipleoftheopticalisolatoris.本题答案：【Ensurethattheopticalsignalcanonlypropagateforward】3、【单选题】Theimportantcomponentstoconverttheopticalpathandrealizetheopticalexchangeare.本题答案：【opticalswitch】Exercises1、【单选题】Thebasicworkingprincipleofopticalamplifieristhe.本题答案：【Stimulatedradiation】2、【单选题】Gainsaturationlimitstheamplifier's.本题答案：【Magnificationability】3、【单选题】Thedegreeofreductionofthesignal-to-noiseratiooftheamplifiedsignalintheopticalamplifierisusuallyexpressedby.本题答案：【Noisefigure】Exercises1、【单选题】Theoperatingwavelengthoftheerbium-dopedfiberamplifierisintherangeof.本题答案：【1530nm-1560nm】2、【单选题】Whichofthefollowingstatementsisincorrect?本题答案：【Thepumppowerrequiredtostimulatetheerbium-dopedfiberisrelativelyhigh】3、【单选题】Intheco-directionalpumpederbium-dopedfiberamplifier,thetransmissiondirectionsofthepumpinglightandthesignallightare.本题答案：【thesame】Exercises1、【单选题】ThepumpwavelengthcurrentlyusedbyEDFAis.本题答案：【0.98μmand1.48μm】2、【单选题】WhichofthefollowingisnottheadvantageofEDFA?本题答案：【Abilityofamplifyingmultiplebands】3、【单选题】WhichofthefollowingisnottheapplicationofEDFA?本题答案：【Equalizationamplifier】Exercises1、【单选题】TheamplificationofopticalsignalsbyfiberRamanamplifiersmainlyutilizestheeffectof.本题答案：【StimulatedRamanscattering】2、【单选题】WhichofthefollowingisincorrectregardingtotheopticalfiberRamanamplifier?本题答案：【FiberRamanamplifiercanonlyamplifysignalsataspecificwavelength】3、【单选题】ThesaturationpowerandamplificationbandofthefiberRamanamplifieraremainlydeterminedby______.本题答案：【Pumpinglight】Test91、【单选题】Thepreamplifierreferstothedevicetightlyconnectedto.本题答案：【Photodetector】2、【单选题】TheopticalamplificationprincipleofEDFAis.本题答案：【stimulatedradiation】3、【单选题】ThefunctionoftheopticalisolatorinEDFAismainlyto.本题答案：【Eliminatetheinfluenceofthereflectedlight】Exercises1、【单选题】ThemeaningofPDHis.本题答案：【Plesiochronousdigitalhierarchy】2、【单选题】WhichofthefollowingstatementsaboutPDHiswrong?本题答案：【ThePDHstandardofChinaisthesameasthoseofNorthAmericaandJapan】3、【判断题】Currently,PDHmostlyadoptssynchronousmultiplexing.本题答案：【错误】Exercises1、【单选题】IntheSDHframestructure,isusedtotransmittheadditionalbyteofnetworkoperation,managementandmaintenance.本题答案：【Sectionoverhead】2、【单选题】IntheSDHSTM-1framestructure,theoverheadbyteoftheregenerationsectionislocatedin.本题答案：【Thefirst9columnsofrows1-3】3、【单选题】WhichofthefollowingdoesnotbelongtotheSDHframestructure?本题答案：【Tributaryunit】Exercises1、【单选题】Mappingrefersto.本题答案：【Theprocessofadaptingthetributarysignaltovirtualcontainer】2、【单选题】istheoverheadusedfornetworkmanagementbetweenvirtualcontainersVC-1/VC-2intheSTM-Nframestructure.本题答案：【Loworderpathoverhead】3、【单选题】Whichofthefollowingbasicunitscancompletetheadaptationbetweenthelow-orderpathlayerandthehigh-orderpathlayer?本题答案：【Tributaryunit】Exercises1、【单选题】TheSDH-specificpointeradjustmentwillexperiencealargephasejumpattheSDH/PDHnetworkboundary,soeverytimethe2Mbit/ssignalusedtotransmitthenetworktimingreferencepassesthroughtheSDHnetwork,theamountthatthepointeradjustsis.本题答案：【8】2、【单选题】TheadjustmentunitoftheTU-12pointerisbytes,andthepointerrangeknownis0-139.本题答案：【1】3、【判断题】SDHpointerisdividedintoAUpointerandTUpointer.本题答案：【正确】Test101、【单选题】OneSTM-4canaccess2Mb/ssignals.本题答案：【252】2、【单选题】IntheSDHframestructure,thepathoverheadisrepresentedby.本题答案：【POH】3、【单选题】Theroleoftheadministrativeunitpointeristo.本题答案：【IndicatetheexactpositionofthefirstbyteofthepayloadintheSTM-Nframe,sothatthereceivercandemultiplexitcorrectly】Exercises1、【单选题】Theclockboardautomaticallyentersaccordingtothememorizeddatawhenallclocksourcesarelost.本题答案：【Holdmode】2、【单选题】ThesynchronousdigitalnetworkofChinaadoptsthemethod.本题答案：【Master-slavesynchronization】3、【单选题】Whichofthefollowingworkingmodesforslaveclocksisthemostaccurate?本题答案：【Trackingsynchronizationmode】Exercises1、【单选题】AsanSDHtransmissionequipment,theterminalmultiplexeris.本题答案：【TM】2、【单选题】WhichofthefollowingisnotanSDHnetworkelement?本题答案：【ONU】3、【判断题】IntheSDHtransmissionnetwork,DXCequipmentisoftenusedinthemeshnetworknodeorthecentralnodeofthestarnetwork.本题答案：【正确】Exercises1、【单选题】TheSDHself-healingringstructurecanbedividedintotwocategories,namely,.本题答案：【Pathprotectionringandmultiplexsectionprotectionring】2、【单选题】SDHself-healingringprotectionswitchingtimeisrequiredtobelessthan.本题答案：【50ms】3、【单选题】InSDHself-healingringprotection,needstouseAPSprotocolforswitching.本题答案：【Two-fiberunidirectionalpathprotectionring】Exercises1、【单选题】TheOTNInterfaceDatarateOUT-1is.本题答案：【2.66Gbit/s】2、【单选题】WhichofthefollowingisnotthecharacteristicoftheOpticalTransportNetwork(OTN)?本题答案：【Inabilitytomanageallwavelengthsinmultipleopticalfibers】3、【判断题】OpticalTransportNetwork(OTN)isatransportnetworkthatisbasedonwavelengthdivisionmultiplexingtechnologyandorganizesattheopticallayer.OTNisthenextgenerationbackbonetransportnetwork.本题答案：【正确】Test111、【单选题】Theclockboardhasbeenworkinginthetrackingmodefor3days,itautomaticallyenterstheholdmodeduetothelossofthetrackingclock,holdingtimecanbeuptohours.本题答案：【24】2、【单选题】Thetwo-fiberbidirectionalmultiplexsectionprotectionringusestechnologytocombinethesignalsontwofibersintoonefiber.本题答案：【Timeslotexchange】3、【单选题】Thefunctionoftheopticalcross-connect(OXC)devicedoesnotinclude.本题答案：【Amplificationfunction】Exercises1、【单选题】Theroleofistoprovideopticalaccessnetworkaninterfacebetweenthenetworksideandthelocalswitch,andtocommunicatewiththeONUattheusersideviaoneormoreODNs.本题答案：【OLT】2、【单选题】Whichofthefollowingisnotequipmentoftheopticalaccessnetwork?本题答案：【ATU-R】3、【判断题】Accordingtotheemploymentofactivedevicesinfacilities,opticalaccessnetworksaredividedintoactiveopticalnetworksandpassiveopticalnetworks.本题答案：【正确】Exercises1、【单选题】APONreferstoPONusingtransmission.本题答案：【asynchronoustransfermode】2、【单选题】ThedownstreamrateofAPONisMb/s.本题答案：【155.52】3、【判断题】APONisEthernetpassiveopticalnetworkofinternationalstandardIEEE802.3ah.本题答案：【错误】Exercises1、【单选题】InEPON,theupstreamanddownstreamdataaretransmittedviatwodifferentwavelengths,namely,.本题答案：【1310nm,1550nm】2、【单选题】EPONhasanupstreamtransmissionrateat1.25GbpsandadownstreamrateatGbps.??本题答案：【1.25】3、【判断题】EPONisapassiveopticalaccesstechnologybasedonATM/GEM,followingtheITU-TG.984seriesofstandards.本题答案：【错误】Exercises1、【单选题】servicescanbecarriedbyGPON.本题答案：【ATM,TDM,andEthernet】2、【单选题】InGPON,along-lightingONUmaycause.?本题答案：【offlineofotherONUsunderthesamePON】3、【单选题】ThemaximumsplitratioadoptedbytheGPONsystemis.本题答案：【1:128】Test121、【单选题】providesanopticaltransmissionmeansbetweenOLTandONU.Itsmainfunctionistocompletethetaskofopticalsignalpowerdistribution.本题答案：【ODN】2、【单选题】TheinternationalstandardofEPONis.??本题答案：【IEEE?802.3ah】3、【判断题】ATMPONiscalledpassiveopticalnetworkbasedonasynchronoustransfermodetechnology.本题答案：【正确】Exercises1、【单选题】isatechnologythattransmitsmultiplewavelengthsignalsinasinglefiber.本题答案：【Opticalwavelengthdivisionmultiplexingtechnology】2、【单选题】Whichofthefollowingtechnologiesisaneffectivewaytoincreasethecapacityofinformationtransmittedoneachchannel?本题答案：【Opticaltimedivisionmultiplexing】3、【单选题】WhichofthefollowingisnotthemainadvantageofWDM?本题答案：【Theadopteddigitalsynchronizationtechnologydoesnotrequirecodeadjustment】Exercises1、【单选题】ITU-TG.692recommendsthattheworkingwavelengthoftheWDMsystemiscurrentlyat.本题答案：【Cband】2、【单选题】Fortheworkingfrequencyofthewavelengthdivisionmultiplexingsystem,whichofthefollowingistheabsolutefrequencyreference(AFR)?本题答案：【193.1THz】3、【单选题】For160×10Gbit/sDWDMsystems,thechannelspacingis?.??本题答案：【50GHz】Exercises1、【单选题】IntheWDMopticaltransportnetwork,theopticalsupervisorychannelconsistsofframealignmentsignalsandpayload,andhasatransmissionrateofMbit/s.??本题答案：【2.048?】2、【单选题】Intheopticaladd/dropmultiplexer,inordertoachievethesamepowerbetweentheaddandpasswavelengthchannels,canbeused.?本题答案：【Variableopticalattenuator?】3、【单选题】OTUinthewavelengthdivisionmultiplexingsystemisresponsibleforconvertingopticalsignalsintoopticalsignalsthatcomplywiththeG.957technicalstandard.本题答案：【Non-standardwavelength】Exercises1、【单选题】Inthe1530~1565nmwindow,whichofthefollowingfibertypessufferfromthemostseverefour-wavemixingeffect?本题答案：【DSF】2、【单选题】isthemaincauseoffour-wavemixing.本题答案：【Zerodispersion】3、【判断题】Atthe1550nmwindowofG.652fiber,thedispersioncoefficientDofthefiberispositive,andthegroupvelocityoftheopticalcarrierisproportionaltothecarrierfrequency.本题答案：【正确】Test131、【单选题】Thecurrentwavelengthdivisionmultiplexingsystemisdevelopednearthewavelengthof.本题答案：【1550nm】2、【单选题】Inthedensewavelengthdivisionsystem,theworkingwavelengthofthesupervisorychannelisat.本题答案：【1510nm】3、【判断题】Accordingtothespacingbetweenwavelengthchannels,WDMcanbedividedintodensewavelengthdivisionmultiplexingandcoarsewavelengthdivisionmultiplexing.本题答案：【正确】Exercises1、【单选题】Thebiterrorrateisoneoftheimportantindicesdescribingthequalityofdatacommunicationsystems.Whichofthefollowingstatementsaboutthebiterrorrateiscorrect?本题答案：【Biterrorrateisanimportantindexthatmeasuresthetransmissionreliabilityofadatacommunicationsystemundernormaloperations;】2、【单选题】Thebetterwaytoevaluateerrorperformanceis.本题答案：【theerrortimeratio】3、【判断题】Driftreferstotheshort-termdeviationofeachvalidmomentofadigitalsignalfromitsidealposition.本题答案：【错误】Exercises1、【单选题】Inthecyclicredundancycheck(CRC),isthecyclicredundancycode.本题答案：【Remainder】2、【单选题】Whichofthefollowingstatementsabouttheerrordetectioncapabilityofthecyclicredundancycheckcodeistrue?本题答案：【Allodd-biterrorscanbedetected】3、【判断题】WhenusingdifferentgeneratorpolynomialstogenerateCRCcodes,theerrorcorrectionabilitiesoftheobtainedCRCcodesarethesame.本题答案：【错误】Exercises1、【单选题】Intheformulaoftheworstvaluealgorithmthatcalculatestheattenuationlimitedrelaydistance,thevalueofthefiberopticcablemargin(MC)issettobedb.?本题答案：【3-5】2、【单选题】Themainfactorthatlimitstherelaydistanceofopticalfibercommunicationsis.本题答案：【Attenuationanddispersion】3、【判断题】Therelaydistanceofthedigitalcommunicationsystemisnotlimitedbydispersion.本题答案：【错误】Exercises1、【单选题】referstotheabilityofaproducttoperformaspecifiedfunctionundergivenconditionsforastatedtimeinterval,whichisoftencharacterizedbyfailurerate.本题答案：【reliability】2、【单选题】referstotheprobabilitythattheproductisingoodworkingconditionunderspecifiedconditionsatastatedtime.本题答案：【availability】3、【判断题】China'snationalstandardsrequiresopticalcommunicationsystemwithmaximum5000kmdistancewillallow8failuresperyear.本题答案：【错误】Test141、【单选题】isatransientinstabilityintheprocessofdigitalsignaltransmission.Itreferstothedeviationofeachvalidmomentofthedigitalsignalfromthestandardtimepoint.本题答案：【jittercharacteristics】2、【单选题】Thesystembiterrorrateoftheopticalcommunicationsystemshouldgenerallybelessthan.本题答案：【】3、【单选题】Inanopticalfibercommunicationsystem,thesystemerrorperformanceisanimportantindexofitsquality.Amongthem,theratioofthenumberoferrorbitsreceivedtothetotalnumberofbitsinthelong-termobservationiscalled?????.本题答案：【Long-termaveragebiterrorrate】Exercises1、【单选题】Opticalsolitoncommunicationrequiresthepulsewidthprovidedbytheopticalsolitonsourcetobeontheorderof.本题答案：【ps】2、【判断题】Opticalsolitonisanultra-shortopticalpulsewhoseamplitudeandwidthremainunchangedafteralong-distancetransmissionthroughoptical