【MOOC】無線通信原理（雙語）-南京郵電大學 中國大學慕課MOOC答案

【MOOC】無線通信原理（雙語）-南京郵電大學中國大學慕課MOOC答案IntroductiontoWirelessCommunicationsIntroductiontoWirelessCommunications1、【單選題】Ifacarrierfrequencyf=60GHzisadoptedforawirelesscommunication,thewavelengthλofthecarrierwaveis___.本題答案：【5mm】2、【單選題】TheBluetoothsystemsbelongtothewirelessnetworkof___.本題答案：【WPAN】3、【單選題】In2000,ITUapprovedthreestandardsofWCDMA,CDMA2000and___.本題答案：【TD-SCDMA】4、【單選題】Forawirelesscommunicationsystem,iftheinputpoweris8dBm,andtheoutputpoweris5dBm,thesystemattenuationis___.本題答案：【3dB】5、【判斷題】Mostcellphonesoperateinthefrequencyrangeof800to2,200KHz.本題答案：【錯誤】6、【判斷題】WIFIisawirelesslocalnetworkthatrunsoftheIEEE802.15standardsset.本題答案：【錯誤】7、【判斷題】Frequencydivisionduplexingsystemusesdifferenttimeslotsfortheforwardandreversechannels.本題答案：【錯誤】8、【判斷題】TheShannoncapacitydeterminesthetheoreticallimitonchannelcapacityforagivenbandwidthandsignal-to-noiseratio.本題答案：【正確】TheCellularConcept:SystemDesignFundamentalsTheCellularConcept:SystemDesignFundamentals1、【判斷題】Inthecellularnetworks,thecoverageareaofeachbasestationisnamedascell.本題答案：【正確】2、【判斷題】IntheN-Cellreusepattern,thefrequencyreusefactoris1/N.本題答案：【正確】3、【判斷題】Inadynamicchannelassignmentstrategy,eachcellisallocatedapredeterminedsetofchannels.本題答案：【錯誤】4、【判斷題】Foraproperhandoffsituation,thehandoverthresholdshouldbesetslightlyweakerthanMinimumusablesignallevel本題答案：【錯誤】5、【判斷題】InanN-cellreusepattern,Ncanchooseanypositivenumber.本題答案：【錯誤】6、【判斷題】Asmallvalueoftheco-channelreuseratioprovideslargercapacity.本題答案：【正確】7、【判斷題】Cellularradiosystemsrelyontrunkingtoaccommodatealargenumberofusersinalimitedradiospectrum.本題答案：【正確】8、【判斷題】Aradiochannelthatisoccupiedfor20minutesduringanhourcarriers20Erlangsoftraffic.本題答案：【錯誤】9、【判斷題】Cellsplittingisusedinhighdensitysubscriberareastodecreasesystemcapacity.本題答案：【錯誤】10、【判斷題】Sectoringhasthecapabilityofdecreasingtheco-channelinterferenceandthusincreasingsystemperformance.本題答案：【正確】MobileRadioPropagation:Large-ScalePathLossMobileRadioPropagation:Large-ScalePathLoss1、【單選題】Theeffectiveradiatedpowerdenotesthemaximumradiatedpowerascomparedtothe___.本題答案：【half-wavedipoleantenna】2、【單選題】Thegrowthrateofthepathlossinfreespaceis___.本題答案：【20dB/decade】3、【單選題】___occurswhenapropagatingwaveimpingesuponanobjectwhichhasverylargedimensionswhencomparedtothewavelengthofthewave.本題答案：【Reflection】4、【單選題】TheQ-functionisdeterminedbythefactorsexceptthe___ofthereceivedsignal.本題答案：【coveragearea】5、【判斷題】Infreespace,thereceivedpowerisproportionaltothecarrierwavelength.本題答案：【正確】6、【判斷題】Thepathlossrepresentssignalgainasapositivedifferencebetweentheeffectivetransmittedpowerandthereceivedpower.本題答案：【錯誤】7、【判斷題】Whenthemediumconsistsofalargenumberofobjectswithdimensionsthataresmallcomparedtothewavelength,scatteringwavecanbeobserved.本題答案：【正確】8、【判斷題】Theclose-inreferencedistance,thepathlossexponentandthestandarddeviationstatisticallydescribethepathlossmodelconsideringrandomshadowingeffects.本題答案：【正確】Small-ScaleFadingandMultipath,andIntroductionofMIMOTechnologiesSmall-ScaleFadingandMultipath,andIntroductionofMIMOTechnologies1、【判斷題】Fadingcanbeclassifiedintosmallscalefadingandlargescalefading.本題答案：【正確】2、【判斷題】Small-scalefadesarecharacterizedbydeepandslowamplitudefluctuationswhichoccurasthemobilemovesoverdistancesofjustafewwavelengths.本題答案：【錯誤】3、【判斷題】Whatisfrequencyflatfading?Atypeofsmallscalefadingwherefrequencysignalcomponentsexperiencedifferentmagnitudesoffading.本題答案：【錯誤】4、【判斷題】Iftheattenuationandpathdelayofacomplexchannelresponsevarywithfrequency,thechanneliscalledatime-variantcomplexchannel.本題答案：【錯誤】5、【判斷題】Forsimulatingafrequencyselectivechannel,discrete-timeTDLfiltersismandatorytohaveN=1whileNisthenumbertapsofthefilter.本題答案：【錯誤】6、【判斷題】TherearemanydiversitymethodstorealizeIndependentfadingpaths,suchasSpaceDiversity,PolarizationDiversity,Frequencydiversityandtimediversity.本題答案：【正確】7、【判斷題】SmallScaleFadingisdividedintotwomain,i.e.,multipathdelayspreadandfrequencyspread.本題答案：【錯誤】8、【判斷題】MIMOstandsfor‘MultipleInput,MultipleOutput’,andisaformofradioantennathatincreasesefficiencybyincreasingthenumberoftransmittersandreceivers.本題答案：【正確】9、【判斷題】MIMOcapacityisindependentonpropagationchannel.本題答案：【錯誤】10、【判斷題】ForabadMIMOchannels,spatialcorrelationishighandthecapacityislow.本題答案：【正確】MultipleAccessTechniquesforWirelessCommunicationsMultipleAccessTechniquesforWirelessCommunications1、【單選題】CDMAusesthepowercontroltocombatthe.本題答案：【near-farproblem】2、【單選題】Whichsystemneedstheequalization?本題答案：【TDMA】3、【多選題】WhichisthefeatureofslottedAloha?本題答案：【Timeisdividedintoequaltimeslots.#Transmitonlyatthebeginningofatimeslot.#Avoidpartialcollisions.#Increasedelay,andrequiresynchronization.】4、【多選題】WhicharefeaturesoftheCDMAsystem?本題答案：【Softhandoff#near-farproblem#self-jammingandsoftcapacitylimit#RAKEreceiver】5、【多選題】_____and____canimprovethecapacityofCDMAsystem.本題答案：【AntennaSectorization#Voiceactivity】6、【判斷題】ThereareTDMA/TDDandTDMA/FDD.本題答案：【正確】7、【判斷題】CDMAissuperiortoTDMAandFDMA.本題答案：【錯誤】8、【判斷題】Spreadspectrumlowersthesignalleverandreducesthebandwidthofchannel.本題答案：【錯誤】9、【判斷題】ThevulnerableperiodinpureAlohaistwopackets,andthevulnerableperiodinslottedAlohaisapacket.本題答案：【正確】10、【判斷題】ThecapacityofFDMAandTDMAsystemisinterferencelimited,whilethecapac