第1題第2題第3題第4題第5題第6題第7題Determinewhetherthefollowingsignalsareperiodicsignals.Ifyes,determineitsperiod.ABCD第8題Determinewhichofthefollowingsignalsareenergysignals,whicharepowersignals,ornoneofthem.ABCD第9題Theinput-outputrelationshipsofthesystemsareasfollows,wherex(t)andy(t)aretheinputandoutputofthecontinuous-timesystems,y(0)areinitialstates,x[k]andy[k]arethe

inputandoutputofthediscrete-timesystems,y[0]areinitialstates.Determinewhetherthesesystemsarelinearsystems?ABCD第10題Determinewhetherthefollowingsystemsaretime-invariantsystems,why?Wherex(t)andx[k]areinputsignals,y(t)andy[k]arezero-stateresponses.ABCD第1題Whichofthebelowdeterministicsignalsisacontinuous-timeenergysignal().ABCD第2題Givenaperiodiccontinuous-timesignal,whatisthesignal'speriodandtheaveragepowerP()?ABCD第3題Giventhebelowrelationshipsbetweenthevoltageandthecurrent,pleasepickthesystemthatistime-variant(

).ABCD第4題Belowarefourdiscrete-timesystemandtherelationshipbetweentheinput,,theoutput,,andtheinitialstate,isgivenforeachofthesystems,whichisnotalinearsystem()?ABCD第5題Giventherelationshipbetweentheinput,theoutput,andtheinitialstate,whichofthesystemsisalinearsystem()?ABCD第6題Whichofthebelowsystemisatime-invariantsystem?Giventhatoristheinputofthesystemandandistheoutput().ABCD第7題Giventhedifferenceequationofadiscrete-timesystemis,thenthesystemis().ACausal,lineartime-invariantsystemBCausal,lineartime-varyingsystemCNon-causal,lineartime-invariantsystemDNon-causal,nonlineartime-invariantsystem第8題Foralinearcontinuous-timesystem,whentheinitialstateisandtheinputsignalis,theoutputis;whentheinitialstateisandtheinputsignalis,theoutputis,thenwhatistheoutputwhentheinitialstateisandtheinputsignalis()?ABCDExerciseforChapter2第1題第2題第3題第4題第5題第6題第7題第8題Determineeachoffollowingformulaswithpropertyofimpulsesignal.ABCD第9題Considerthewaveformofsignalx(t)isshowninFigure2，sketcheachoffollowingsignals.A

x(-2t-5)；Bx(t)+u(t)；Cx(t)u(1-t)；D

x'(t)第10題Given

twosequencesand

,pleasesketchthewaveformsofthefollowingsequences.

ABCDHomeworkforChapter2第1題Asinusoidalsignalcanberepresentedbyusingimaginaryexponentialsignalas().ABCD第2題Whichoneofthebelowdescriptionsoftheimaginaryexponentialsignalisnotcorrect().ABoththeimaginaryexponentialsignalandthesinesignalareperiodicsignalswiththefundamentalperiodof.BTheimaginaryexponentialsignalcanberepresentedas.CBoththeimaginaryexponentialsignalandthesinesignalcanbelinearlyrepresentedbytheothersignal,andthus,theyhavethesameproperties.DThegreaterthe,thehighertheoscillationfrequencyoftherealandimaginarypartsoftheimaginaryexponentialsignal.第3題

Given

thewaveformofasignal,

asshownbelow,itcanberepresentedas(

).ABCD第4題=().ABCD第5題Thevalueoftheintegralis().A0B4C-4D2第6題WhichoneofthebelowrelationsisWRONG().ABCD第7題WhichoneofthebelowdescriptionsoftheimaginaryexponentialsequenceisWRONG().ATheimaginaryexponentialsequenceisnotnecessarilyperiodic.BTheimaginaryexponentialsequenceandsinusoidalsequencescanrepresenteachotherusingtheEuler'srelation.CTheimaginaryexponentialsequencecanbeobtainedbysamplingfromthecontinuous-timesignal,therefore,theyshouldhavethesameperiod.DTheamplitudeoftheimaginaryexponentialsequencemaynotincreaseastheangularfrequencyincrease.第8題WhichoneofthebelowrelationsisWRONG()?ABCD第9題

Given

thewaveformofsignalshownbelow,thesignalcanberepresentedbyusingandas(

).ABCD第10題

Given

thewaveformofasignalshownbelow,thewaveformofx′(t)

shouldbe(

).ABCD第11題

The

waveformofasignalshownbelow,whatisthewaveformof(

).ABCD第12題If,,then=().ABCD第13題

Given

thewaveformofthesignalshownbelow,whichoneoftherepresentationofiswrong(

).ABCD第14題Ifadiscrete-timesequence,thenwhichofthefourexpressionsisNOTtheevencomponentof().ABCD第15題Asinusoidalsignalcanberepresentedbyusingimaginaryexponentialsignalas().ABCD第16題Whichoneofthebelowdescriptionsoftheimaginaryexponentialsignalisnotcorrect().ABoththeimaginaryexponentialsignalandthesinesignalareperiodicsignalswiththefundamentalperiodof.BTheimaginaryexponentialsignalcanberepresentedas.CBoththeimaginaryexponentialsignalandthesinesignalcanbelinearlyrepresentedbytheothersignal,andthus,theyhavethesameproperties.DThegreaterthe,thehighertheoscillationfrequencyoftherealandimaginarypartsoftheimaginaryexponentialsignal.第17題Giventhewaveformofasignal,asshownbelow,itcanberepresentedas().ABCD第18題=().ABCD第19題Thevalueoftheintegralis().A0B4C-4D2第20題WhichoneofthebelowrelationsisWRONG().ABCD第21題WhichoneofthebelowdescriptionsoftheimaginaryexponentialsequenceisWRONG().ATheimaginaryexponentialsequenceisnotnecessarilyperiodic.BTheimaginaryexponentialsequenceandsinusoidalsequencescanrepresenteachotherusingtheEuler'srelation.CTheimaginaryexponentialsequencecanbeobtainedbysamplingfromthecontinuous-timesignal,therefore,theyshouldhavethesameperiod.DTheamplitudeoftheimaginaryexponentialsequencemaynotincreaseastheangularfrequencyincrease.第22題WhichoneofthebelowrelationsisWRONG()?ABCD第23題Giventhewaveformofsignalshownbelow,thesignalcanberepresentedbyusingandas().ABCD第24題Giventhewaveformofasignalshownbelow,thewaveformofshouldbe().ABCD第25題Thewaveformofasignalshownbelow,whatisthewaveformof().ABCD第26題If,,then=().ABCD第27題Giventhewaveformofthesignalshownbelow,whichoneoftherepresentationofiswrong().ABCD第28題Ifadiscrete-timesequence,thenwhichofthefourexpressionsisNOTtheevencomponentof().ABCDExerciseforChapter3第1題第2題第3題第4題第5題第6題第7題第8題HomeworkforChapter3第1題Ifthezero-state(ZS)responseofaC-Tlineartime-invariant(LTI)systemtotheunitstepsignalis,

thentheimpulseresponseofthesystemis(

).ABCD第2題Iftheimpulseresponseofdiscrete-time(D-T)LTIsystemis,thentheunitstepresponseofthesystemis().ABCD第3題AssumingthattheinitialstateofaC-TLTIsystemisnotzero,iftheinputis,thefullresponseofthesystemis,now,iftheinputincreasesto2,thefullresponseofthesystemwill().Aincreasesto2Bincreasesbutlessthan2CremainasDchangesbutnoneoftheabovearecorrect第4題Thedifferentialequationofa2ndorderC-TLITsystemis,andtheinitialstateincludesy(0?)

and

y′(0?),thenthezero-input(ZI)responseis(

).ABCD第5題Thedifferentialequationofa2ndorderC-TLTIsystemis,thentheformoftheimpulseresponseofthesystemis().ABCD第6題If,then().ABCD第7題WhichoneofthebelowsignalisNOTequalto().ABCD第8題

ForaC-TLTIsystem,theinputandtheimpulseresponseofthesystemareshownbelow,thenthevalueoftheZSresponseofthesystematt=1is(

).A-2B-1C0D1第9題TheimpulseresponseofaC-TLTIsystemis,iftheinput,thentheZSresponseofthesystemis().ABCD第10題The

differentialequationofaC-TLTIsystemis

y″(t)+5y′(t)+4y(t)=2x′(t)+5x(t),,Iftheinitialstateofthesystemisnotzero,theinput,andthefullresponse,thenthenaturalresponseofthesystemis(

).ABCD第11題IfthedifferenceequationofaD-TLTIsystemis,Andtheinitialstateofthesystemincludes=1,,thenthezero-inputresponseofthesystemis().ABCD第12題ThedifferenceequationofaD-TLTIsystemis,Thentheimpulseresponseofthesystemis().ABCD第13題TheimpulseresponseofaD-TLTIsystemis,

theinput,thenZSresponseofthesystemat=3(

).A2B3C4D5第14題TheimpulseresponseofaD-TLTIsystemis,,Iftheinputis,thentheZSresponseofthesystemis().ABCD第15題GiventhatthedifferenceequationofaD-TLTIsystemis,,iftheinitialstateofthesystemisnotzero,theinputis,andthefullresponse,thenthetransientresponsethesystemis().ABCD第16題TheimpulseresponsesoftwoC-TLTIsystemsareand,respectively,ifthesetwosystemsareinparallelconnection,thentheimpulseresponseoftheoverallsystemis().ABCD第17題

TheoverallimpulseresponseoftheD-TLTIsystemshownbelowis(

).ABCD第18題Theimpulseresponseofamovingaveragesystemwithis,then,thesystemis().Anon-casual、stableBcasual、unstableCnon-casual、unstableDcasual、stableHomeworkforChapter4第1題ThereasonforGibbsphenomenonisthatonlyalimitednumberofFourierseriestermsareusedtorepresentperiodicsignals().A√B×第2題Thefasterthesignalinthetimedomainchanges,themorethehigh-frequencycomponentthesignalhas().A√B×第3題Ifthemaximumfrequencyofagivensignal,x(),isHz,andthesamplingfrequency,thenthesampledsignalwillhavealiasing().A√B×第4題Ifasignalisshiftedinthetimedomain,thenitsamplitudespectrumwillremainthesamewhileitsphasespectrumwillhavephaseshift().A√B×第5題Ifacontinuous-timesignalisextendedinthetimedomain,thenitwillhavemorehigh-frequencycomponents().A√B×第6題Nomatterforcontinuousordiscrete-timesignals,thespectrumofaperiodicsignalisalwaysdiscreteandthespectrumofanon-periodicsystemisalwayscontinuous().A√B×第7題Ifaperiodiccontinuous-timesignal,,ispowersignal,thenitsFouriertransformdoesnotexist().A√B×第8題Thesumoftheaveragepoweroftheharmonicsinsidetheeffectivebandwidthtakesthemajoritypartoftheaveragepowerofthewholesignal().A√B×第9題Ifthespectrumofanon-periodicsignalis,thentheyareinone-to-onecorrespondence().A√B×第10題Foranycontinuous-timesignal,theamplitudespectrumisevenwhilethephasespectrumisodd().A√B×第11題

The

waveformofacontinuous-timesignalisshownbelow,whatfrequency

componentsdoesthesignalhave(

)?ACosinecomponentsforallharmonicBSinecomponentsforallharmonicCSinecomponentsforoddharmonicDCosinecomponentsforoddharmonic第12題

Given

thespectrumofacontinuous-timesignalisshownbelow,then,theperiodic

signal=(

).ABCD第13題

For

aperiodicsignalshownbelow,theDCcomponentis(

).A0B2C2.5D4第14題Theaveragepowerofperiodiccontinuous-timesignalis().A6B6.5C8D8.5第15題The

spectrumofanon-periodiccontinuous-timesignalis().Acontinuousandnon-periodicBcontinuousandperiodicCdiscreteandnon-periodicDdiscreteandperiodic第16題TheFouriertransformofsignalis().ABCD第17題Givenasignal,thevalueofthespectrumat,is().A0B4C8D16第18題Ifthebandwidthofthebandlimitedsignalis,thenthebandwidthofthesignalis().A2BCD4第19題Thehighestangularfrequencyofthespectrumofonesignalis,andthehighestangularfrequencyofthespectrumofasecondsignalis,then,thehighestangularfrequencyofthesignalis().ABCD第20題

A

signalisshownbelow,thespectrumofsignalis(

).ABCD第21題Ifthehighestfrequencyofarealsignalis,thenthehighestfrequencyofthesignalis().A100HzB150HzC200HzD400Hz第22題Theenergyofthesignalis().ABCD第23題

If

theFouriertransformofthesignalshowninFigure(a)is,

thentheFouriertransformofthesignalinFigure(b)is().(a)

(b)ABCD第24題Thespectrumofthesignalis,thenthespectrumofthesignalis().ABCD第25題Ifthespectrumofarealcontinuous-timesignalis,thenthespectrumofsignalis().ABCD第26題Givenavoicesignal,ifwetransformthesignaltoanewsignal,whatwillthenewsignalbedifferentfromtheoriginalsignal().AThelengthofwillbelongerandthepitchwillbehigherBThelengthofwillbelongerandthepitchwillbelowerCThelengthofwillbeshorterandthepitchwillbehigherDThelengthofwillbeshorterandthepitchwillbelower第27題Foraperiodicdiscrete-timesequence,thespectrumis,ifthespectrumofanotherperiodicdiscrete-timesignalis,thenthevaluesofthesequenceatare().ABCD第28題Ifthespectrumofadiscretesequenceis,thenthespectrumofsignalis().ABCD第29題Given

atime-limitedsequence,

thenthevalueofthespectrumx(ejΩ)atΩ=0

is=(

).A1B2C3D5第30題Assumingthatthefrequencyofthesignalis,ifonesamplesthesignal,toavoidaliasing,whatisthemaximumofthesamplinginterval()?ABCD第31題Whichofthebelowstatementsiscorrect,intermsofthesamplingtheoryinthetimedomain()?ATheshorterthesamplinginterval,thebetter.BThesamplingfrequencymustbegreaterthanorequaltothemaximumfrequencytimestwo.CItisnotnecessarythatthesampledsignalcontainsalltheinformationofthecontinuous-timesignal.DDiscretizationinthetimedomaincorrespondstoperiodizationinthefrequencydomain.第32題

The

spectrumofacontinuous-timesignalis

x(jω)

,

showninthefigurebelow,ifonesamplesthesignalatasamplingfrequencytoobtainadiscrete-timesignal,

thenthespectrumofthediscrete-timesignalis

x(ejΩ),

giventhat,

whichofthebelowspectrumis

x(ejΩ)?

(

).ABCDHomeworkforChapter5第1題ThedifferentialequationofacausalandstableC-TLTIsystemis,then,thefrequencyresponseofthesystemis().ABCD第2題TheunitimpulseresponseofaC-TLTIsystemis,thenthefrequencyresponseofthesystemis().ABCD第3題TheunitimpulseresponseofaC-TLTIsystemis,thefrequencyresponseofthesystem=().ABCD第4題ThefrequencyresponseofaC-TLTIsystemis,iftheinputis,thentheZSresponseofthesystemis().ABCD第5題ThefrequencyresponseofaC-TLTIsystemis,theZSresponseofthesystemtotheinputis().ABCD0.2第6題GiventhatthefrequencyresponseofaC-TLTItransmissionsystemisthesystemis().AadistortionlesstransmissionsystemBatransmissionsystemwithadistortionlessamplituderesponsebutadistortedphaseresponseCatransmissionsystemwithadistortionlessphaseresponsebutadistortedamplituderesponseDatransmissionsystemwithdistortedamplitudeandphaseresponses第7題Thefrequencyresponseofanidealanaloglow-passfilterisIftheinputsignalis,thentheZSresponseofthesystem=().A1B2CD第8題IftheunitimpulseresponseofaC-TLTIsystemis,thentheamplituderesponseofthesystemis().Alow-passBhigh-passCband-passDband-stop第9題ThedifferenceequationofaD-TLTIsystemis,thenthefrequencyresponseofthesystem=().ABCD第10題TheunitimpulseresponseofaD-TLTIsystemis,thenthefrequencyresponseofthesystem=().ABCD第11題TheunitimpulseresponseofaD-TLTIsystemis,iftheinputis,thentheoutputofthesystemis=()ABCD第12題TheunitimpulseresponseofaD-TLTIsystemis,theamplituderesponseofthesystemis().Alow-passBhigh-passCband-passDband-stop第13題AnAMradiostationisbroadcastingamusicalsignalwiththehighestfrequencyof10kHz,giventhatthestationusesadouble-bandamplitudemodulationandthefrequencyofthecarrieris800kHz,thentheupperandlowercutofffrequenciesare().A790kHz,810kHzB790kHz,800kHzC800kHz,810kHzD800kHz,820kHz第14題

Shown

intheblowdiagramisaC-Tsystem,ifthespectrumoftheinput

signalis,the

spectrumoftheoutputis(

).ABCDHomeworkforChapter6第1題x(t)=2r(t?1)?3r(t?2)+r(t?4),

theunilateralLaplacetransformis(

).ABCD第2題,

thentheinitialvalueof,is(

).A1B0CdoesnotexistD-1第3題,

thenthefinalvalueof,is().A1B0CdoesnotexistD-1第4題,theninverseLaplacetransformof,is().ABCD第5題TheimpulseresponseofaC-TLTIsystemis.Theinputas,whenanalyzingthezero-stateresponseinthecomplexfrequencydomain,whichofthebelowstepsiswrong?().AFindtheunilateralLaplacetransformof,BFindtheunilateralLaplacetransformof,CFindthezero-stateresponseinthecomplexfrequencydomainDTaketheinverseLaplacetransformof,tofindthezero-stateresponseinthetimedomain第6題Given

thattheregionofconvergence()ofthebilateralLaplace

transformof,is,is(

).

ABCD正確答案：C第7題Thetransferfunctionsoftheidealintegratoranddifferentiatorare().AB1,C,1D,第8題IfthetransferfunctionofaC-TLTIsystemis,thenthesystemis()ALowpassBHighpassCBandpassDBandstop第9題Thezero-stateresponseofaC-TLTIsystemtoaninput,is,thenthetransferfunctionofthesystemis().ABCD第10題ThetransferfunctionofaC-TLTIsystemis,thenthesystemis().ACausalandstableBNon-causalandstableCCausalandunstableDNon-causalandunstable第11題AcausalC-TLTIsystemis,thenthetransferfunctionandtheunitinpulseresponseare().A,B,C,D,第12題

The

zero-poleplotofaC-TLTIsystemisshownbelow,and,Then

theunitimpulseresponseofthesystemis(

).ABCD第13題

The

blockdiagramofacausalC-TLTIsystemisshownbelow,thenthe

transferfunctionofthesystemis().ABCD

第14題ForacausalC-TLTIsystem,iftheinputis,thenthezero-stateresponseis,nowiftheinputischangedto,thecorrespondingzero-stateresponsewillbechangedto.Thentheinputis().ABCD第15題

If

thebelowcausalC-TLTIsystemisstable,whatconditionshouldsatisfy?(

).ABCD第16題AcausalC-TLTIsystemisandtheinitialstateandtheinput,whencalculatingthesystem'szero-inputandzero-stateresponsesandtheunitimpulseresponse,whichofthebelowstepsiswrong?().ATakeunilateralLaplacetransformonbothsidesofthedifferentialequation,BCalculatethezero-inputresponseCCalculatethezero-stateresponseDCalculatetheunitimpulseresponseHomeworkforChapter7第1題Ifthez-transformofis,thenis().ABCD第2題Iftheunilateralz-transformofis,thenis().ABCD第3題Iftheunilateralz-transformofis,thentheunilateralz-transformandtheregionofconvergence()ofis().ABCD正確答案：C第4題Iftheunilateralz-transformofis,then

x[∞]()Ais0Bis1Cis∞D(zhuǎn)doesnotexist第5題Iftheunilateralz-transformofis,,thenis()A0B1C-1D∞第6題Given,theinversez-transformofis()ABCD第7題Thezero-stateresponseofaD-TLTIsystemtotheinputis,thenthetransferfunctionofthesystemis()ABCD第8題IftheunitimpulseresponseofaD-TLTIsystemish[k]=δ[k]?(14)ku[k],thenthedifferenceequationofthesystemis().ABCD第9題Thezero-stateresponseofaD-TLTIsystemtoaunitstepsequenceu[k],whichalsocalledtheunitstepresponse,is

g[k]=(12)ku[k],thenthezero-stateresponseofthesystemtotheinputx[k]=(13)ku[k],

is