信号与系统第四章习题解答.ppt

1,Homework:4.34.44.104.114.144.154.244.254.324.354.364.374.43,2,ConsideranLTIsystemwhoseresponsetothesignalinFigure(a)isthesignalillustratedinFigure(b).DetermineandsketchcarefullytheresponseofthesystemtotheinputdepictedinFigure(c).,3,2.LetbeasignalwithFouriertransform.Supposewearegiventhefollowingfacts:(1).isreal.(2).for.(3).Determineaclosed-formexpressionfor.,4,5,6,ConsideranLTIsystemillustratedinFigure(a),supposewearegiven,+,-,Figure(a),Determinetheresponseofthesystemtotheinput,7,8,4.3DeterminetheFourierTransform,9,4.4DeterminetheinverseFouriertransform:,10,4.10.(a)DeterminetheFouriertransformof(b)Determinethenumericalvalueof,11,12,Solution,13,4.12ConsidertheFouriertransformpair(a)FindtheFouriertransformof(b)DeterminetheFouriertransformof,14,4.14ConsiderasignalbeasignalwithFouriertransform.Supposewearegiventhefollowingfacts:(1).isrealandnonnegative.(2).WhereAisindependentoft.(3).Determineaclosed-formexpressionfor.,15,16,17,18,(a),(d),(e),(f),(a),(b),(e),(f),(a),(b),(c),(d),(f),(b),(c),(e),(f),(b),19,Constructasignalthathasproperties(1),(4),and(5)anddoesnothavetheothers.,1.,4.,5.,3.Theredoesnotexistarealsuchthatisreal.,isnoteven.,6.isnotperiodic,Forexample,20,isrealevenfunction.,(b)Find,(c)Find,21,(d)Evaluate,22,(e)Evaluate,(f)SketchtheinverseFouriertransformof,23,4.32ConsideranLTIsystemSwithimpulseresponseDeterminetheoutputofSforeachofthefollowinginputs:,24,25,26,27,28,Solution1,Solution2,29,(b)Sket