Signals and Systems with MATLAB

490 Pages·2009·4.34 MB·English

by  Won Young Yang (auth.)

Signals and Systems with MATLAB(cid:2)R
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· · ·
Won Y. Yang Tae G. Chang Ik H. Song
· · ·
Yong S. Cho Jun Heo Won G. Jeon
·
Jeong W. Lee Jae K. Kim
Signals and Systems
(cid:2)
with MATLAB R
123
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Theauthorsandpublisherofthisbookhaveusedtheirbesteffortsandknowledgein
preparingthisbookaswellasdevelopingthecomputerprogramsinit.However,they
make no warranty of any kind, expressed or implied, with regard to the programs or
thedocumentationcontainedinthisbook.Accordingly,theyshallnotbeliableforany
incidentalorconsequentialdamagesinconnectionwith,orarisingoutof,thereaders’
useof,orrelianceupon,thematerialinthisbook.
[e-mail].
Programfilesinthisbookcanbedownloadedfromthefollowingwebsite:
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MATLABandSimulinkproductinformation,pleasecontact:
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ISBN 978-3-540-92953-6 e-ISBN 978-3-540-92954-3
DOI10.1007/978-3-540-92954-3
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Preface
This book is primarily intended for junior-level students who take the courses on
‘signalsandsystems’.Itmaybeusefulasareferencetextforpracticingengineers
andscientistswhowanttoacquiresomeoftheconceptsrequiredforsignalprocess-
ing.Thereadersareassumedtoknowthebasicsaboutlinearalgebra,calculus(on
complex numbers, differentiation, and integration), differential equations, Laplace
transform,andMATLAB(cid:2)R.Someknowledgeaboutcircuitsystemswillbehelpful.
Knowledge in signals and systems is crucial to students majoring in Electrical
Engineering. The main objective of this book is to make the readers prepared for
studying advanced subjects on signal processing, communication, and control by
covering from the basic concepts of signals and systems to manual-like introduc-
tions of how to use the MATLAB(cid:2)R and Simulink(cid:2)R tools for signal analysis and
filterdesign.Thefeaturesofthisbookcanbesummarizedasfollows:
1. It not only introduces the four Fourier analysis tools, CTFS (continuous-time
Fourierseries),CTFT(continuous-timeFouriertransform),DFT(discrete-time
Fouriertransform),andDTFS(discrete-timeFourierseries),butalsoilluminates
therelationshipamongthemsothatthereaderscanrealizewhyonlytheDFTof
thefourtoolsisusedforpracticalspectralanalysisandwhy/howitdiffersfrom
theotherones,andfurther,thinkabouthowtoreducethedifferencetogetbetter
informationaboutthespectralcharacteristicsofsignalsfromtheDFTanalysis.
2. Continuous-time and discrete-time signals/systems are presented in parallel to
savethetime/spaceforexplainingthetwosimilaronesandincreasetheunder-
standingasfarasthereisnoconcernovercausingconfusion.
3. It covers most of the theoretical foundations and mathematical derivations that
willbeusedinhigher-levelrelatedsubjectssuchassignalprocessing,commu-
nication,andcontrol,minimizingthemathematicaldifficultyandcomputational
burden.
4. Mostexamples/problemsaretitledtoillustratekeyconcepts,stimulateinterest,
orbringoutconnectionswithanyapplicationsothatthereaderscanappreciate
whattheexamples/problemsshouldbestudiedfor.
5. MATLAB(cid:2)R is integrated extensively into the text with a dual purpose. One
is to let the readers know the existence and feel the power of such software
tools as help them in computing and plotting. The other is to help them to
vii
viii Preface
realizethephysicalmeaning,interpretation,and/orapplicationofsuchconcepts
asconvolution,correlation,time/frequencyresponse,Fourieranalyses,andtheir
results,etc.
6. The MATLAB(cid:2)R commands and Simulink(cid:2)R blocksets for signal processing
application are summarized in the appendices in the expectation of being used
likeamanual.Theauthorsmadenoassumptionthatthereadersareproficientin
MATLAB(cid:2)R . However, they do not hide their expectation that the readers will
get interested in using the MATLAB(cid:2)R and Simulink(cid:2)R for signal analysis and
filterdesignbytryingtounderstandtheMATLAB(cid:2)R programsattachedtosome
conceptuallyorpracticallyimportantexamples/problemsandbeabletomodify
themforsolvingtheirownproblems.
The contents of this book are derived from the works of many (known or
unknown)greatscientists,scholars,andresearchers,allofwhomaredeeplyappre-
ciated. We would like to thank the reviewers for their valuable comments and
suggestions,whichcontributetoenrichingthisbook.
WealsothankthepeopleoftheSchoolofElectronic&ElectricalEngineering,
Chung-AngUniversityforgivingusanacademicenvironment.Withoutaffections
and supports of our families and friends, this book could not be written. Special
thanksshouldbegiventoSeniorResearcherYong-SukParkofKETI(KoreaElec-
tronics Technology Institute) for his invaluable help in correction. We gratefully
acknowledge the editorial and production staff of Springer-Verlag, Inc. including
Dr.ChristophBaumannandMs.DivyaSreenivasan,Integra.
Any questions, comments, and suggestions regarding this book are welcome.
[e-mail].
Seoul,Korea WonY.Yang
TaeG.Chang
IkH.Song
YongS.Cho
JunHeo
WonG.Jeon
JeongW.Lee
JaeK.Kim
Contents
1 SignalsandSystems............................................. 1
1.1 Signals ................................................... 2
1.1.1 VariousTypesofSignal .............................. 2
1.1.2 Continuous/Discrete-TimeSignals ..................... 2
1.1.3 AnalogFrequencyandDigitalFrequency................ 6
1.1.4 PropertiesoftheUnitImpulseFunction
andUnitSampleSequence ........................... 8
1.1.5 SeveralModelsfortheUnitImpulseFunction............ 11
1.2 Systems .................................................. 12
1.2.1 LinearSystemandSuperpositionPrinciple .............. 13
1.2.2 Time/Shift-InvariantSystem........................... 14
1.2.3 Input-OutputRelationshipofLinear
Time-Invariant(LTI)System.......................... 15
1.2.4 ImpulseResponseandSystem(Transfer)Function........ 17
1.2.5 StepResponse,PulseResponse,andImpulseResponse.... 18
1.2.6 SinusoidalSteady-StateResponse
andFrequencyResponse............................. 19
1.2.7 Continuous/Discrete-TimeConvolution ................. 22
1.2.8 Bounded-InputBounded-Output(BIBO)Stability ........ 29
1.2.9 Causality........................................... 30
1.2.10 Invertibility......................................... 30
1.3 SystemsDescribedbyDifferential/DifferenceEquations ......... 31
1.3.1 Differential/DifferenceEquationandSystemFunction..... 31
1.3.2 BlockDiagramsandSignalFlowGraphs................ 32
1.3.3 GeneralGainFormula–Mason’sFormula............... 34
1.3.4 StateDiagrams...................................... 35
1.4 DeconvolutionandCorrelation ............................... 38
1.4.1 Discrete-TimeDeconvolution.......................... 38
1.4.2 Continuous/Discrete-TimeCorrelation .................. 39
1.5 Summary ................................................. 45
Problems ................................................. 45
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