信号与系统（全英文）知到智慧树章节测试课后答案2024年秋北京理工大学

信号与系统（全英文）知到智慧树章节测试课后答案2024年秋北京理工大学第一章单元测试

Theperiodofis（）。

A:B:C:D:

答案:Theperiodofis（）。

A:15B:30C:3D:10

答案:30andaretheinputandoutputsignalsofthesystemrespectively,andonly（）belowisacausalLTIsystem.

A:B:C:D:

答案:（）。

A:B:C:D:

答案:（）。

A:B:C:D:

答案:Amemorylesssystemmustnotbeacausalsystem.（）

A:对B:错

答案:错AcascadeoftwoLTIsystemsisalsoaLTIsystem.（）

A:错B:对

答案:对Acascadeoftwononlinearsystemsisstillanonlinearsystem.（）

A:错B:对

答案:错timeshiftstobecome,andwhen,istotheleftof.（）

A:对B:错

答案:对Theproductoftwooddsignalsortwoevensignalsisanevensignal.（）

A:错B:对

答案:对Theproductofanoddsignalandanevensignalisanevensignal.（）

A:对B:错

答案:错Theunitimpulseresponseofadelaywithatimedelay​foraCTsignalis,theunitimpulseresponseofanintegratoris,andtheunitimpulseresponseofadifferentiatoris.（）

A:错B:对

答案:对

第二章单元测试

TheimpulseresponseofaCTlinearcausalsystemmustsatisfycondition（）。

A:B:C:D:

答案:Given,（）。

A:B:C:D:

答案:ForaCTLTIsystem,iftheinput-outputrelationshipisgivenby,thenthesystem'sunitimpulseresponseis（）.

A:B:C:D:

答案:Given,then。（）

A:对B:错

答案:错Given,then。（）

A:对B:错

答案:对Given,and,,then,。（）

A:错B:对

答案:对Given,and,,then,。（）

A:错B:对

答案:对Givenasystemwithinput-outputrelationshipas,and,thesystemistime-invariant.（）

A:对B:错

答案:对Givenasystemwithinput-outputrelationshipas,thesystemisnon-linear.（）

A:错B:对

答案:错Givenasystemwithunitimpulseresponseas,thesystemisastableLTIsystem.（）

A:对B:错

答案:对Givenasystemwithunitimpulseresponseas,thesystemisastableLTIsystem.（）

A:对B:错

答案:错

第三章单元测试

Giventhatisafunctionwithaperiod,thentheFourierseriesof

A:正弦分量B:偶次谐波分量C:奇次谐波分量D:余弦分量

答案:奇次谐波分量Assumingaperiodicsignalwithperiodand,,withFourierseriescoefficientsdenotedas​,then（）。

A:0B:2C:4D:1

答案:4isaCTperiodicsignalwithafundamentalfrequencyandFouriercoefficients.Giventhat

,thefundamentalfrequency

andtheFourierseriescoefficients

of

are(

).

A:，B:，C:，D:，

答案:，ACTLTIsystemhasafrequencyresponse.Whentheinputisaperiodicsignalwiththefundamentalperiod​andFourierseriescoefficients,theoutputisobservedtobe.Whatconditionsmustthecoefficientssatisfy?（）.

A:，B:，C:，D:，

答案:，GiventhatisaperiodicsignalwithperiodandsatisfiestheDirichletconditions,canberepresentedasaFourierseries.Iftheseriesistakenwithafinitenumberofterms,therewillbeanerror;iftheseriesistakenwithaninfinitenumberofterms,themeansquareerrorapproacheszero.（）

A:错B:对

答案:对AssumingisaCTperiodicsignal,itsFourierseriesrepresentationisgivenby,thenthesignalisreal-valued.（）

A:错B:对

答案:错AssumingisaCTperiodicsignal,itsFourierseriesrepresentationisgivenby,thenthesignalisreal-valued.（）

A:错B:对

答案:对AssumingisaCTsystemwhoseresponsetothecomplexexponentialinputis,thenthesystemisdefinitelynotLTI.（）

A:对B:错

答案:对AssumingisaDTsystemwhoseresponsetothecomplexexponentialinputis,thenthesystemisdefinitelynotLTI.（）

A:错B:对

答案:错GiventhatisarealandevenCTperiodicsignal,withFourierseriescoefficients​,then​isanevenfunction.（）

A:对B:错

答案:错

第四章单元测试

TheconditionfortheexistenceoftheFouriertransformofthesignalis（）.

A:B:不存在C:D:

答案:Giventhat,theconvolutionequationthatdoesnotholdamongthefollowingis（）.

A:B:C:D:

答案:GiventheFouriertransformofas,thentheFouriertransformofis（）。

A:B:C:D:

答案:GiventheFouriertransformofas,thentheFouriertransformofis（）。

A:B:C:D:

答案:TheimaginarypartoftheFouriertransformofacontinuous-timesignalcorrespondstotheoddcomponentofthesignal.（）

A:对B:错

答案:对TheFouriertransformofanon-periodicsignalisnecessarilycontinuousinthefrequencydomain.（）

A:错B:对

答案:对TheFouriertransformconvertsasignalfromthetimedomaintothefrequencydomain,butitdoesnotpreserveallofthesignal'sinformation.（）

A:对B:错

答案:错IftheFouriertransformofasignalisreal,thenthesignalmustbeanevenfunction.（）

A:错B:对

答案:对GiventhataCTLTIsystemhasafrequencyresponse​,thesystemisadistortion-freetransmissionsystem.（）

A:对B:错

答案:错Giventhatistheinputtothesystemandistheoutput,thensystemandsystem​areinversesystemsofeachother.（）

A:错B:对

答案:错

第五章单元测试

TheperiodofDTsignalis（）。

A:12B:12C:8D:24

答案:24TheFouriertransform

ofDTsignalis（）。

A:B:C:D:

答案:TheFouriertransformofDTsignalis（）。

A:B:C:D:

答案:GiventheFouriertransformofDTsignalas,thentheFouriertransformofis（）。

A:B:C:D:

答案:GiventheFouriertransformofDTsignalas,thentheFouriertransformofis（）。

A:B:C:D:

答案:TheFouriertransformoftheDTsignalisperiodic.（）

A:对B:错

答案:错Thespectrumofaperiodicsignalisdiscrete.（）

A:对B:错

答案:对GiventhattheFouriertransformoftheDTsignalis,thesignalispurelyimaginary,neitheroddnoreven.（）

A:错B:对

答案:对GiventhattheFouriertransformofthediscrete-timesignalis,thesignalisarealevenfunction.（）

A:对B:错

答案:错GiventheFouriertransformofDTsignalas,if,then。（）

A:对B:错

答案:对

第六章单元测试

Anideallow-passfilterdescribedbytheimpulseresponseis（）.

A:IndeterminateB:UnstableC:StableD:Marginallystable

答案:UnstableGivenacontinuous-timeideallow-passfilterwithimpulseresponse​;when,theoutputis（）.

A:B:C:D:

答案:GivenaCTLTIsystemwiththeunitimpulseresponse,where​;thesystemis（）.

A:Band-passfilterB:Low-passfilterC:High-passfilterD:All-passfilter

答案:Low-passfilterGivenaDTsystemwithitsunitstepresponseas,theunitsampleresponseis（）。

A:B:C:D:

答案:GivenaCTsystemwithaunitfrequencyresponseas,asignalwill（）afterpassingthroughthesystem.

A:ExperienceasmoothingeffectB:NotundergoanychangeC:HaveitsedgesenhancedD:Sufferphasedistortion

答案:HaveitsedgesenhancedAfterpassingthroughadistortion-freetransmissionsystem,theunitstepfunctionresultsinanoutputsignaloftheform.（）

A:对B:错

答案:对GivenaDTidealhigh-passfilterwithfrequencyresponseas,asdecreases,theunitimpulseresponseofthefiltermovesfurtherawayfromtheorigin.（）

A:对B:错

答案:对GivenaCTidealhigh-passfilterwithfrequencyresponseas,asincreases,theunitimpulseresponseofthefiltermovesfurtherawayfromtheorigin.（）

A:对B:错

答案:错Aband-limitedlow-passfilterwithfrequencyresponse​​canbeimplementedinhardwareintherealworld.（）

A:对B:错

答案:错IftheunitimpulseresponseofaCTLTIfilterisalwaysgreaterthanorequaltozero,thenthefilter'sstepresponseisamonotonicallynon-decreasingfunction.（）

A:错B:对

答案:对

第七章单元测试

GivenaCTsignal,theDTsignalobtainedbysamplingatasamplingfrequencyis（）.

A:B:C:D:

答案:GiventhattheNyquistsamplingfrequencyofthesignalis,thentheNyquistsamplingfrequencyforthesignalis（）.

A:B:C:D:

答案:GiventhattheNyquistsamplingfrequenciesforsignalsandare​and​respectively,and​,thentheNyquistsamplingfrequencyforis（）.

A:B:C:D:

答案:Giventhatthebandwidthofthesignalis,theNyquistsamplingintervalforis（）.

A:B:C:D:

答案:Giventhatthebandwidthsofsignalsandare​and​respectively,and​,thentheNyquistsamplingintervalforis（）.

A:B:C:D:

答案:Giventhatthehighestangularfrequencyofthesignalis​,whensamplingand,themaximumsamplingintervalsthatpreventaliasingintheirspectraare（）.

A:，B:，C:，D:，

答案:，Forband-limitedsignals,thehigherthesamplingfrequency,thehighertheprecisionwithwhichtheoriginalsignalcanberecovered.（）

A:对B:错

答案:对Thesamplingtheoremappliesonlytocontinuous-timesignalsandisnotapplicabletodiscrete-timesignals.（）

A:对B:错

答案:错WhenaCTsignalisideallysampledwithasamplinginterval,thefrequencypointofinthecontinuousdomaincorrespondstoanangularfrequencyvalueofinthediscretedomain.（）

A:错B:对

答案:错

第八章单元测试

GiventhattherelationshipbetweentheinputandtheoutputofaDTsystemis

,thesystemis（）.

A:StableB:CausalC:Time-invariantD:Linear

答案:CausalGiventhattherelationshipbetweentheinputandtheoutputofanLTIsystemis,thesystemis（）.

A:Non-causal,unstableB:Causal,unstableC:Causal,stableD:Non-causal,stable

答案:Causal,stableGivensignalsasand,iftheproductpassesthroughanideallow-passfilterwithacutofffrequencyofandapassbandgainof2,thenthesignalobtainedattheoutputofthelow-passfilteris（）.

A:B:C:D:

答案:InaLTIsystem,iftheinputsignalisandthesystem'sunitimpulseresponseis,thenthesystem'soutputcanberepresentedas(

).

A:B:C:D:

答案:Inanidealdistortion-freetransmissionsystem,theamplitudeandphaseofthesignalshouldremain（）duringtransmission.

A:BothamplitudeandphasechangeB:Amplitudechanges,phaseremainsthesameC:Amplituderemainsthesame,phasechangesD:Bothamplitudeandphaseremainunchanged

答案:BothamplitudeandphaseremainunchangedInacommunicationsystem,themainpurposeofmodulationis（）.

A:Toincreasethesignal'sfrequencyB:Toreducethesignal'snoiseC:ToimpressinformationontoacarrierfortransmissionD:Tochangethesignal'swaveform

答案:ToimpressinformationontoacarrierfortransmissionALTIsystem'sresponsetoadelayedinputsignalwillchangeboththeshapeofthesignalandthetimeatwhichthesignaloccurs.（）

A:错B:对

答案:错Infrequencydomainanalysis,ifthespectraoftwosignalsdonotoverlap,thenthetwosignalsmustbeorthogonalinthetimedomain.（）

A:对B:错

答案:对Giventhatisareal-valuedsignalwith,and,toensurethatcanberecoveredfrom,itisnecessarythat.（）

A:对B:错

答案:错Giventhatisareal-valuedsignalwith,and,toensurethatcanberecoveredfrom,itisnecessarythat.（）

A:错B:对

答案:对

第九章单元测试

GiventhattheimpulseresponseofacertainLTIsystemis,thezero-stateresponsetotheinputsignalis（）.

A:B:C:D:

答案:GiventheLaplacetransformas​,theinitialvalueoftheoriginalsignalis（）。

A:DoesnotexistB:-5C:4D:-4

答案:DoesnotexistTheinverseLaplacetransformofis（）。

A:B:C:D:

答案:TheunilateralLaplacetransformofsignalis（）。

A:B:C:D:

答案:Consideringastableandcausalsystemwithanimpulseresponseandasystemfunction.Assumingisrational,withapoleat,nozerosattheorigin,andthelocationsoftheremainingpolesandzerosareunknown.Thecorrectstatementamongthefollowingis（）.

A:B:hasatleastonepoleinitsLaplacetransformC:convergesD:

答案:hasatleastonepoleinitsLaplacetransformGiventhatacausaldiscreteLTIsystemhasasystemfunction​,anditsinversesystemisalsocausal,thentheinversesystemis（）.

A:CannotdetermineitsstabilityB:MarginallystableC:StableD:Unstable

答案:StableThenecessaryandsufficientconditionforthestabilityofaDTLTIsystemisthatallthepolesofthesystemfunctionarelocatedwithintheunitcircle.（）

A:对B:错

答案:错TheLaplacetransformisanextensionoftheFouriertransform,whichisapplicabletobothnon-periodicandperiodicsignals.（）

A:错B:对

答案:对Givenastableandcausalsystemwitharational,havingapoleat,theFouriertransformofdoesnotexist.（）

A:对B:错

答案:错TherearetwoCTsystemsgivenasand.Whenthesesystemsarecascaded,theoverallsystemisanon-memory(memoryless)system.（）

A:对B:错

答案:对

第十章单元测试

Givenabilateralsequence,thez-transformofis（）.

A:B:C:D:

答案:Theoriginalsequencecorrespondingtotheunilateralz-transformtransferfuncti