Students and working professionals will find Signals ond Signals and Systems Systems with MATLAB ® Computing and Simlink ® : © Commuting | Modeling Fouth Edfion to be a concise and easy
Trang 1—_
Signals and Systems
with MATLAB ® Com ting
and Simulink ® Modeli
Fifth Edition
Steven T, Karris
Trang 2Students and working professionals will find Signals ond
Signals and Systems Systems with MATLAB ® Computing and Simlink ®
: © Commuting | Modeling Fouth Edfion to be a concise and easy to-eam with MATLAB ® Computing | tog itprvides complete cleer end deals explenatons and Simulink ® Modeling ~ |) ertne pieipalancleg and dicta sonel processing
Fifth Edition ‘concepts and analog and digital fiter design illustrated
with numerous practical examples This text includes the following chapters and appendices
+ Elementary Signals + The Laplace Transformation + The Inverse Laplace Transformation + Circuit Analysis with Laplace Transforms + State Variables and State Equations + The Impulse Response and Convolution + Fourier Series + The Fourier Transform + Discrete Time Systems and the Z Transform + The DFT and The FFT Algorithm + Analog and Digital
Filters + Introduction to MATLAB © ~ Introduction to Simulink ® + Review of Complex Numbers + Review of Matrices and Determinants + Window Functions + Correlation
Functions + The Describing Function in Nonlinear systems
Each chapter and appendixcontains numerous practical applications supplemented with detailed instructions for using MATLAB and Simulink to obtain accurate and quick solutions,
ISBN 978-1-98/404.28-2
Visitus on the Intemet www orcharpublieatons.comor email us: Info@orchardpublicatons com
9l7ã1934 leDa2321 |
ISBN-13: 978-1-934404-23-2
Trang 3Sigal and Stems with MATLAB® Conon ad Sink Medel, ath ico
Coppght © 2012 Orchant Publiations AM hts seve Pied in he Unie States of America, No pot of hi tral yb eprnced x tte at faa oy sy teas some in sda eo tonal se
‘thou the peor saben peeaisin of the pbs
Ti ll inquses to Orchard Publktins infdtonhandpblitionssonn
MalladsPt lạc Thọ se vu sub ly cm xen and exanaton,wiehou aero ge tralemarks of the Mictosof™ Corporation and The Library of Congress Cataloging-in-Pablication Data
Catalog con ene ra the Library of Conese
brary of Congress Cnt Nonier: 2011939678
ISBN-13; 978-1-934404-23-2
ISBN-10; 4-934404-23-3
Copwricht TXu 1-778-061
Trang 4Preface
‘This text contains a comprehensive discussion on continuous and discrete tine sstals atl syste with many MATLAB® and several $i
clectrical and computer engineering students, and for self-study by worhi
prerequisites area basic course in diiercritial and integral vale, and hast electric eiouit theory
anulink® examples, Te is written for jumior and senior
professionals The This book ean be Usel in two-quarter, or oe semester course, This author has taught the subject
lecture hours per
; Appenslix E contains a comprehensive dis describes the cross correlation and autocorrelation funetions, and Appendix G presents at exausple
function
ais theo ion on window fametions, Appendix F
‘ofa nonlinear systeny and derives its describ
New to the Fifth Edition
The mest notable change is the addition of Appendives F and G All chapters and appendises are resvrtten and the MATLAB scripts and Simulink towels are hase on Releate R2011b (MATLAB, Version 7.13, Simulink Version 2.8)
Trang 5The author wishes to express his gratitude to the staff of The MathWorks, the developers of MATLAB® and Sinulink®, especially to The MathWorks™ Book Program Tent tor the encouragement and unlimited support they hase provided me with during the production of this and all sther texts by eis publisher
(Our heartielt thanks also « Ms Sally Wright, PE, of Renewable Energy Research Laboratory University of Massachusetts, Amberst, for bringing some errors and suggestions on a previous edition to our attention
Orchant Publications
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‘nfo@orchardpublications com
Trang 6Table of Contents
LLL Signals Describes in Math Forms ra L3 The Unie Step Function 2
14.1 The Sampling Property of the Dela Function bit 14.2 The Sitting Peoperty af the Delta Function
2 The Laplace Transformation
Definition of the Laplace Teansfomsation
Properties and Theoreis of the Laplace Transtortn
2.1 Linearity Property Tine Shitting Property Frequency Shifting Property Sealing Property
Dilferentiation in Tite Domain Propesty Ditierentiation in Complex Frequency Domain Property lnteg
28 Inteyration in Complex Frequency Domain Property
9 Tiove Periosicity Property
10 tnitial Valse Theorems 2.11 Final Value Theorem
4 The Laplace Transforns of the Delta Function (1) EU 23.5 The Laplace Tratisforts ofthe Delayed Delta Function ð(t 2 Signals and Sytems ath MATLAB ® Computing and Simulink ® Modeling
Consight © Orshard Publications th Edition i
Trang 723.6 The Laplace Transforn of “uy
38 The Laplare Transom of snout The Laplace Transfors of te i
39 The Laplace Transloris of sos mt
2.3.10 The Laplare Transtonis of © “snot v0)
23.11 The Laplace Transfony of « Moose! uy()
2.4, The Laplace Tratsfonts of Connon Wavetons
24.1 The Laplace Transform of a Pale
24.2 The Laplace Transfornt of a Linear Sestnent
3/43 The Laplace Transior of a Triangular Wavetors
244 The Laplace Transiorn of a Rectangular Periodic Wavetorn
2.45 ‘The Laplace Transloet of a Hali-Rectified Sine Wavetorn
Using MATLAB for Finling the Laplace Transioens of Time Functions
Sususay
Exerciscs
The Laplace Tranatoee of s Sawtooth Periodic Wavetorin
The Laplace Tranatoroi ofa Pull-Reciied Sine Waveform
Solutions to End-ot-Chapter Exercise
‘The Inverse Laplace Transform,
3.1 The Inverse Laplace Transiorm Inteural
3.2 Partial Fraction Expansion,
3.2.1 Distinct Poles
Complex Poles
3.2.3 Multiple (Repeated) Poles
3 Case wliere Fis) is Improper Rational Function
4 Altesnate Method of Partial Fraction Expansion
Signa cin Systems with MATLAB ® Computing and Simulink ® Madling, Eh Eilitiom
Coprright © Orturd Publications
Trang 845 Using the Simulink Transier Fon Block
F State Variables and State Equations
5.1 Expressing Differential Equations in State Equation Form
5.2 Solution of Single State Equations
5.3 The State Transition Matrix
5.4 Computation of the Stare Transition Matrix
5.4.1 Distinct Bigenvalcs 5.4.2 Multiple (Repeated) Bigerwalucs
55 Bigenvectors
5.9 Circuit Analisis with Stare Varinhles
5.7 Relationship hetween State Equations and Laplace Teanstorm
G The Impulse Response and Convolution
6.1 The Impulse Response in Time Domain
6.2, Byen ang Odd Punetions of Time:
63 Convolution,
(64 Graphical Evaluation of the Convolution Integral
65 Circuit Analysis with the Convolution Integral
Signals and Sytems ath MATLAB ® Computing and Simulink ® Modeling
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Trang 97 Fourier Series
TA Wave Analysis
Exaluation of the Coefficients
7.3 Sitntetay itn Trigonmetric Fourier Series
73.1 Ssmmezry in Square Waveform
7.3.2 Ssmmezey in Square Waveforon with Ordinate Axis Shite
7.33 Ssanmetry in Sawtooth Wavetor
734 Ssmmerry in Triangular Waveiorm
7.35 Soumetry in Fondawsental, Second, and Thisd Hasionies
74 Trigonometric Fors of Fourie Series for Common Waveforms
TALL Teigonometric Fourie Series for Square Wavelorm
JA.2 Tngonometnc Fourice Series tor Sawtooth Wavefo
TAB Trigonometric Fourier Seties for Triangular Waseforns
TA44 Trigonometric Fourier Series for Half Wave Rectifier Waveform
TAS Trigonometric Fourier Series for Full-Wave Rectifier Waveform
7.5 Gibhs Phenomenon
7.6 Alternate Forms of the Trigonometric Fourier Series
1.7 Circuit Analysis with Trigonomettic Fourier Series
7.8 The Exponential Forus of the Fourier Series
7.9 Svinnetry in Exponential Fourier Series
7.1L Computation of RMS Values from Fourier Series
7.12, Computation of Average Power trom Fourier Series
7.13 Bxahiation of Fourier Coeflicients Using Excel
2.14 Bsaluation of Fourier Coefliciens Using MATLAB®
8.1 _Deinition and Special Fors 54
82 Special Forins of the Fourier Transform 82
w Signal and Sostems with MATLAB ® Conpating and Sinunk ® Madelng, Eth ition
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Trang 103
testis and Theorens of the Fourier Transtar 89
Tinne Seal
Time Shitting Frequency Shitting Time Dilfecenciation Frequency Dillerentiation, Tame Integration
8.3.9 Conjugate Tine and Frequency Functions
84 Fourier Trandom Paice of Common Functions
84.1 The Delta Function Pair
84.2 The Constant Function Pair
843 The Cosine Function Pair
3⁄44 The Sine Function Pair 84.5 The Signum Function Pair 84.6 The Unit Step Function Pair
8.5 Derivation of the Fourier Transform from the Laplace Transforus
8.6 Fourier Transforms of Common Wavelorns
8.6.1 The Transom ðf = Alu/t+TJ=ult- T)Ị 8.6.2 The Transform of 11) = Alo/0 - 01-211
63 TheTrmvfotnef Hộ = Aluit*T1tdg0—vi =A 20] c8 28
&64 The enfonecf Nụ = Aeea,fogL+) nút ĐỊ =
865 The Trai oa Peele Tne Function wih PeiodT =
&66 TúeTiaviotacftiePoáele Time Fandio tụ = 4 Ÿ 8u.) „8 30 8:7 Using MATLAB fr Fg the Four Tandon of Tiác Rivtoie
cuit Analisis, 84
88 ‘The System Function and Applications to
Signals and Sytems ath MATLAB ® Computing and Simulink ® Modeling
Consight © Orshard Publications
Trang 119.2.2 Shit of thonalul in the Discrete-Time Dowsait
9.2.3 Right Shift in the Discrete-Time Domain,
9.24 Lelt Shift in the Diserete-Time Domain
9/35 Mulkiplcation by a in the Disorete—Time Domain
9.2.6 Mulkiplication by &**" in the Discrete-Time Domain,
9.2.7 Muleiplcation by andl n! in the Discrete-Time Domain
9.2.8 Summation in the Discrete-Time Detain
9.2.9 Convolution in the Discrete-Time Domain,
9.2.10 Convolution in the Diensete-Eeluenoy Doruaim
9.2.11 Initial Value Theorem
9.2.12 Final Value Theorem,
9.3 The % Transform of Conon Discrete-Time Functions
9.3.1 The Transfortu of the Geometeie Sequence
9.3.2 The Transori of the Discrete- Tite Unit Step Function
9.3.3 The Transtort of the Discrete-Time Exponential Sequence
9.34 The Transtoruu of the Discrete~Time Cosine and Sine Functions
9.35 The Transort of the Diserete—Tiaie Unit Ramp Fanetion,
9.4 Computation of the % Transform with Contour Integration
9.5 Transformation Between s= and z-Domains
9/6 The Inverse X Transion
8.46.1 Partial Fraction Expansion
9.6.2 The Inversion Integral
9.6.3 Long Division of Polytomials
98.7 The Transler Function of Discrete-Time Systems
9.8 State Equations for DiseveteTime Systems
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Trang 12Simulink Modeling
Page 9-40
Excel Plots
Pages 9-32, 9-40
LO The DFT and the FFT Algorithm
IO.L The Discrete Fourier Transform (DET),
10.2 Even and Odd Properties of the DFT
10,3 Common Properties and Theorets of the DET
103/1 Lineacity 103.2 Tite Shit 10.3.3 Frequency Shit
103.4 Tinie Convolution 103.5 Frequency Coneoluion
104 The Sampling Theorem
10.5 Nutaber of Operations Required to Compare the DFT
19.0 The Fast Fourier Transforta (FFD,
AL Analog and Digital Filters
LIAL Filter Types anid Classifications,
11.2 Basic Analoy Filters
11.2.1 RC Low-Pass Fer 1.2.2 RC High Pass Filter 11.23 RLC Band-Pes Bilier 1.24 RLC Band-Elimination Filter 11.3 Love-Pase Analog Biter Pootorvyes
113.1 Boterwosth Analoyg LowPacs Filter Design 113.2 Chebyshev Type [ Analog Low-Pass Filter Desizn 113.3 Chebyshev Type Hl Analog Low-Pase Filter Design|
11.3.4 Bllipgic Analow Low—Pase Filter Design
114 High-Pass, Band-Pass, and Band-Elimination Filter Design
Signals and Sytems ath MATLAB ® Computing and Simulink ® Modeling
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Trang 13164 The Parallel Fort Realization of a Digital Filter H72
1165 The Dighal Filter Design Block tt
Ad Polynomial Construction from Known Roots A4
AS Evaluation of a Polynomial at Specitied Values AS
A9 Mulhipleaten, Dtdon, and Esponentiation ACT
MATLAB Computing
Pages A-3 through A-D, ALL, A-13, A-15, A-I6,
A-D0, A-1, A-23, A~26, A-27
tals aad Systoms with MATLAB ® Camping a Simin ® Meveling, Fifth Eilition
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Trang 14Simulink Modeling
Pages 8-7, B-I2, B-14, BIS
CA Review of Complex Numbers
C.1 Definition ofa Complex Number,
C.2 Addition and Subtraction of Complex Nurabers ° C3 Multiplication of Complex Numbers é
°
e
C4 Division of Complex Numbers
C.5 Exponential and Polar Forms of Complex Numbers
D_ Matrices and Determinants
Dil Matrix Definition,
D2 Matrix Operations
D.3_ Special Foenis of Matrices
D4 Determinants
DS Minors and
Dio Cramer's Rule
D7 Gaussian Elimination Method
D8 The Adioint of a Matrix,
D9 Singular and Non-Singular Matrices
D.10 The Inverse ofa Matrix
iLL Solution of Situltancous Equations with Mattices
E Window Functions
E.L Window Function Detined
E2 Commision Window Bunctions
EZ Rectangular Window Punction E22 Triangular Window Function
Signals and Sytems ath MATLAB ® Computing and Simulink ® Modeling
Consight © Orshard Publications
Trang 15E23 Hanning Window Function
£24 Hamming Window Function E25 Blackman Window Function E.26 Kaiser Family of Winslow Functions E3 Other Window Functions
4 Fourier Series Method lor Approximaning an FIR Annplituce Response
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Trang 16Chapter 1 Elementary Signals
(Other forms ofthe unit step function are shown in Figure 18,
“AC -AMCLST) -Au 1)
Figure 18, Other rs ofthe unt ste fntton
Unit step fimotions can he used to represent other time-varying functions such as the rectangular pulse shown in Figure 19,
The unit step lunetion offers a convenient mietliod of describing the siden application of a voltage
‘or eurvent sauce, For example, a constant voltage source of 26 V applied at t = 0 can be denoted
as Muy(t) VI, Likewise, a sinusoidal voltage sourre v(t) = Veost V that ie applied toa cout at
1 > ty, cam be described as v(t) = (Vj c0s@t}uy(t—ty) V- Also if te excitation in a cieuit isa
teetangtlar, or triangular, or sawtooth, or anyother recurritw pulse, it ean he represented as a sui (iffeence) of unit sep lunetions
14 nals and Sater with MATLAB ® Computing and Simslink ® Modeling, Fifth Elton
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Trang 17
Higher Order Delta Functions
8 Todeaga point along the x-axis, we select that point, and we hold down the Shift key while dag
syms k a':% Define symbolic variables
U=K*sym(Heaviside(ta))% Create unit step function at
The MATLAB heaviside function can be used! to plot the unit step, unit impulse, and unit ramp
in Figure 1.30, and the unit
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Trang 18Chapter 2: The Laplace Transformation
2.2.3 Frequency Shifting Property
‘The feynoncy shifting jsoferty tates that iTwe multiply a tinue dowain function f(t) by at exponen
rial imecion ef where a isan arbitrary positive constant, this multiplication will predluce a shilt
of the s variable in the complex recuency domain by a units Thus,
eye F(s+ a) (14)
⁄t£“RÓ) = fretane ta = fine? a = rere)
Note 2:
A clianige of scale ts represented by wsultiplication ofthe tite variable ( by a positive scaling lactor
4, Thuis the funetion f(t) after scaling the tinte axis, becomes fat)
and Ìetling E= 9/4, e ehtain
2.2.5 Differentiation in Time Domain Property
‘The diffeentiation in tine domain property states that differentiation in the time domain corte spond to multiplication by i the complex frequency domain, minus the intial value of RQ) at
1 = 0, Thus,
24 ‘Siguals and Sutems with MATLAB Ÿ Computing and Sindink ® Modeling, Fit Edition
Copyright © Orchard Publications
Trang 19Laplace Transforms of Common Fanctions of Time
|ð [Time Priodiey f(t+nT) on J ioe “a vn
10 [onal Ve Tico tin FO Be lim SPC) = 0)
we
AL | Final Value Theorem Tim fc) bo vi lim sF(s) = (==)
| Tine Comin en Fore
B[ Fane Gonolaren — [q00 a5 FuwFas) pers
Signals and Systems with MATLAB © Computing and Simulink ® Modeling, Fifth Edition 213
`
Trang 20Chapter 3
‘The Inverse Laplace Transformation
his chapter tsa continuation to the Laplace transioemation topic ofthe previous chapter and presents several methods of finding the Inverse Laplace Transformation, The partial fraction, expansion mith is explained thoroughly and iis illustrated with several examples
3.1 The Inverse Laplace ‘Transform Integral
The Inverse Laplace Transform Integral was stated in the previous elapters tis repeated here for
3.2 Partial Fraction Expansion
Quite often the Laplace transform expressions are not in recognizable forts, but in tiost eases appear itv a rational form of Seat is,
Ina proper tational function, the roots of N(s) i (3.3) are found by setting N(s) = 0; these are called the zac of F(s) The roots of Bs), found by setting Dis) = 0, are called the pues of F(s)
‘We assume that F(s) iy 3.3) iea proper rational function, Tlen, itis customary and very cone riient to make the eoeicient of unity; thus, we eowrite PS) ác
Signal and Systems with MATLAB ® Computing and Simoink ® Modeling, Fiflt Edition + Corght© Cieked Diiliatdone
Trang 21Partial Fraction Expansion
‘The value of the residue ess can also be found without differentiation as follows:
Substitution ofthe already known values of rand ry into (3.44), and letting s = 0°, we obsain
Trang 22Chapter 3 The Inverse Laplace Transformation
(Check with MATLAB:
3 Muliplies polynomials dt and d2 to express the
% denominator D(s} of F(s) as a polynomial Irp.KIEresidue(Ns Da)
We observe that there isa pole of wuliplicty 3 at š = =1, and a pole of multiplicity 2 at s = 2
Then, in partial fraction expansion forms, F,(s) is written as
jp
The resichtes are
3-10 Signals and Sytem with MATLAB ® Computing and Simatlink © Meeting, Fifth Edom
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Trang 23Chapter 4 Circuit Analysis with Laplace Transforms
Figure 4.10, Plot of Yay (0) forthe eit of Example 4.3
4.2 Complex Impedance Zis)
Consider the domain RLC series circuit of Figure 4.11, where the initial conditions are assured to be 2et,
and delinins the rao V,(S)/1(S) as 2¢3), 9 obtain
48 Signalsand Systems with MATLAB * Compasing and Simink ® Madeling, Ff Edin
Copyright © Orchard Pudicaions
Trang 24‘Using the Simulink Transfer Fen Block
W=1:10:10000; Gs=~1.(2 6"10.A-6) "w22-8 "J*10.^(-8) "w+8);
‘semilogx(w.abs(Gs)); xlabel(Radian Frequency w), vlabel(|VoutVin[),
tile Magnitude Vout/in vs Radian Frequency’; grid
“The plot is shown in Figure 4.22, We observe that the given op amp circuit isa second order low pass filter whose cutoff frequency (-3 4B) occurs at about 700 £/s
Magnitude Vout/Vin ve Racin Frequency
GO" VAG) RICK FURR TC GRC] |
Signals an Stems with MATLAB ® Computing and Simulink ® Modeling, Fifth Edition +
Copmright © Onchand Publications
Trang 25‘Chapter 5 State Variables and State Equations
This citi contains only one ened
state variable, We choose the state variable to denote the wt storing device, the capacitor Therefore, we need only one arrose the capacitor as show in
54 ‘Signals and Systems with MATLAB ® Computing an! Sonadink ® Moaeling, Fi Edition
Copyright © Orchard Publications
Trang 26Computation of the State Transition Matrix
"xổ ta, yet = eM
“(|
‘We use as many equations as the number of the eigenvalues, and we solve for the coefficients
4, Wesubstitute the a, coeilicients into the state tsansition matrix of (5.54), and we snap Example 5.7
Compute the state transition mattix ¢™ given that
ancl expansion ofthis determinant yields the polynomial
‘We will use MATLAB roots(p) function to obtain the roots of (5.57)
p={1 -6 11-6}; rroots(o: forint ìn); fprinti(lambdat = 96.21, r(1)
frin(lambda2 = %5:24' (2); fprint(lambdas = %5.2F,r3))
Jambéat = 3.00 lambda2 = 2.00 lanbda3 = 1.00
andl thos the eigenvalues are
2, Since A isa 33 matris, we use the first 3 terms of (5.54), thạt
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Trang 27‘Chapter 5 State Variables and State Equations
We can obtain the plot of Figure 5.8 with the Simulink State-Space block with the unit step func tion as the input using the Step hlock, and the capacitor voltage as the output displayed on the Scope block as shown in the model of Figure 5.9 where for the State-Space block Function Block
naranicters dialog box we have entered
‘We compute the eigenvalues from
5-26 Signals snd Systeme with MATLAB ® Computing and Simulink ® Modeling, Eifh Ein
© Orchand Publications
Coppi
Trang 28‘Chapter 6 The Impulse Response and Convolution
so = J “eX *bucride = of “ebuceyee (62)
6.4 Graphical Evaluation of the Convolution Integral
The convolution integral is more conventently evaluated by the graphical evaluation, The procedure
is beat illustrated with the followin exaunples
where + ia duasny variable, thats, u(x) and! f(s), ate conserel tobe the same as ult) an
1) We form u(t—t) by fiest constructing the itiage of u(t) this i shown as a(-s) in Figure 6.7
Figuce 6.8 Formation of u(t—t) for Example 64
68 Signals and Sytems with MATLAB ® Contin and Sinking ® Mein, Bifth Eton
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Trang 29‘Chapter 6 The Impulse Response and Convolution
Trang 30Evaluation of the Coefficients
Also ifm and m are different intewers, then,
Sigua and Systems with MATLAB * Compating and Simulink ® Modeling, Fife Edition 23 Commight © Orchard Publications
Trang 31‘Trigonometric Form of Fourier Series for Common Waveforms ics will be present since this wavelorm has also half-wave sywnmetty However, we will compute all coetficients to verify this Als, tor brevity, we will assume that «2
Figore 712, Square waveform as ol fein
‘The a, coefficients are fund from
and since n isan integer (positive or negative) or seto, the terms inside the parentheses on the see-
o, as expected since the square
cond line of (7.19) are sen and therefore, all a, coelficients at
waveform has odd symmetry Also, by inspection, the average (DC } value is 2et0, but if we attenspe
to verte this using (7.19), we will obtain the indeterminate forns 0/0 To work ateund this prob-
“The b, soefkientx are fount from (LM), Page 7-6, thats
by 2 [ff asinnta= fe aysionat = A Ceosmiis ~ cosm?*)
ĐỀ Ị 20
+ ung — chưng) = Â (I-Begnx cam) For n = even, (7.20 vekls
+= Aaron
as expected since the square waveform has half-wave symmetry
Signals and Systems with MATLAB ® Computing and Simulink ® Modeling, Fifth Eiition TAL
Commight © Orchard Publications
Trang 32Chapter 7 Fourier Series
7.8 The Exponential Form of the Fourier Series
The Fourier series ae often expressed in exponential form, The advantage ofthe exponential foron
ro performs one integration rather than ‘wo, one for the a, andl another fo
into A(t) Thus,
Signals und Sytems with MATLAB Computing and Simalink ® Modeling, Fil Edition
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Trang 33
Chapter 8 The Fourier Transform
main Canerponence (Completed Ta
and Fig(-O) = =FjmlA) — T0) = Real (8.32)
Now, if F(@) of some function of tine f(e) és known, and Fh) issuch that F(-@) = F*(@), can
we conclude that ((0) is real! The answer is yes; we ean very this with (814), Page 8-3, which is repeated liere foe eonvenience
fat) ~ Ef UF snot + Fi ycorenide (835)
We olerve that the integrand of (8.35) i eto since its an edd function with respect to @ erase
both prolactin the bracket ate oak fonetions
Therefore, fg) = 0, thats (4) is real
Accordingly, we can state that « necessary and sufficient condition for f(t) to be teal, és that FC) = Fre)
má
ve id a Fg iene and Fig) Wo
88 Siqualsand Systems with MATLAB ® Computing and Simuink ® Madeling, if Edin
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Trang 34
Fourier Transform Pairs of Common Functions
‘TABLE 8.8 Fourier Transform Propernes and Theorems
NỈ Time Shatin s Tw to Flole Fa
Tim Tin tay 7 gar"Frey )
a Frequency Dileoutiation auto N
inne Conon DI) Fo Fe)
Frequenay Common | TF) Le cerrst