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Table of Contents
Chapter 1 - Signal Representation and Modeling
Chapter Objectives
1.1 Introduction
1.2 Mathematical Modeling of Signals
1.3 Continuous-Time Signals
1.3.1 Signal operations
1.3.2 Basic building blocks for continuous-time signals
1.3.3 Impulse decomposition for continuous-time signals
1.3.4 Signal classifications
1.3.5 Energy and power definitions
1.3.6 Symmetry properties
1.3.7 Graphical representation of sinusoidal signals using phasors
1.4 Discrete-Time Signals
1.4.1 Signal operations
1.4.2 Basic building blocks for discrete-time signals
1.4.3 Impulse decomposition for discrete-time signals
1.4.4 Signal classifications
1.4.5 Energy and power definitions
1.4.6 Symmetry properties
1.5 Further Reading
MATLAB Exercises
Computing and graphing continuous-time signals
Describing signals using piecewise linear segments
Signal operations for continuous-time signals
Creating periodic signals
Functions for basic building blocks
Computing and graphing discrete-time signals
Periodic extension of a discrete-time signal
Problems
MATLAB Problems
MATLAB Projects
Chapter 2 - Analyzing Continuous-Time Systems in the Time Domain
Chapter Objectives
2.1 Introduction
2.2 Linearity and Time Invariance
2.2.1 Linearity in continuous-time systems
2.2.2 Time invariance in continuous-time systems
2.2.3 CTLTI systems
2.3 Differential Equations for Continuous-Time Systems
2.4 Constant-Coefficient Ordinary Differential Equations
2.5 Solving Differential Equations
2.5.1 Solution of the first-order differential equation
2.5.2 Solution of the general differential equation
2.5.3 Finding the natural response of a continuous-time system
2.5.4 Finding the forced response of a continuous-time system
2.6 Block Diagram Representation of Continuous-Time Systems
2.7 Impulse Response and Convolution
2.7.1 Finding impulse response of a CTLTI system
2.7.2 Convolution operation for CTLTI systems
2.8 Causality in Continuous-Time Systems
2.9 Stability in Continuous-Time Systems
2.10 Approximate Numerical Solution of a Differential Equation
2.11 Further Reading
MATLAB Exercises
Testing linearity of continuous-time systems
Testing time invariance of continuous-time systems
Using linearity to determine the response of the RC circuit
Numerical solution of the RC circuit using Euler method
Improved numerical solution of the RC circuit
Problems
MATLAB Problems
MATLAB Projects
Chapter 3 - Analyzing Discrete-Time Systems in the Time Domain
Chapter Objectives
3.1 Introduction
3.2 Linearity and Time Invariance
3.2.1 Linearity in discrete-time systems
3.2.2 Time invariance in discrete-time systems
3.2.3 DTLTI systems
3.3 Difference Equations for Discrete-Time Systems
3.4 Constant-Coefficient Linear Difference Equations
3.5 Solving Difference Equations
3.5.1 Finding the natural response of a discrete-time system
3.5.2 Finding the forced response of a discrete-time system
3.6 Block Diagram Representation of Discrete-Time Systems
3.7 Impulse Response and Convolution
3.7.1 Finding impulse response of a DTLTI system
3.7.2 Convolution operation for DTLTI systems
3.8 Causality in Discrete-Time Systems
3.9 Stability in Discrete-Time Systems
3.10 Further Reading
MATLAB Exercises
Writing functions for moving average filters
Testing the functions written in MATLAB Exercise 3.1
Writing and testing a function for the exponential smoother
Iteratively solving a difference equation
Implementing a discrete-time system from its block diagram
Discrete-time system of MATLAB Exercise 3.5 revisited
Convolution using MATLAB
Implementing a moving average filter through convolution
Problems
MATLAB Problems
MATLAB Projects
Chapter 4 - Fourier Analysis for Continuous-Time Signals and Systems
Chapter Objectives
4.1 Introduction
4.2 Analysis of Periodic Continuous-Time Signals
4.2.1 Approximating a periodic signal with trigonometric functions
4.2.2 Trigonometric Fourier series (TFS)
4.2.3 Exponential Fourier series (EFS)
4.2.4 Compact Fourier series (CFS)
4.2.5 Existence of Fourier series
4.2.6 Gibbs phenomenon
4.2.7 Properties of Fourier series
4.3 Analysis of Non-Periodic Continuous-Time Signals
4.3.1 Fourier transform
4.3.2 Existence of Fourier transform
4.3.3 Developing further insight
4.3.4 Fourier transforms of some signals
4.3.5 Properties of the Fourier transform
4.3.6 Applying Fourier transform to periodic signals
4.4 Energy and Power in the Frequency Domain
4.4.1 Parseval’s theorem
4.4.2 Energy and power spectral density
4.4.3 Autocorrelation
4.5 System Function Concept
4.6 CTLTI Systems with Periodic Input Signals
4.6.1 Response of a CTLTI system to complex exponential signal
4.6.2 Response of a CTLTI system to sinusoidal signal
4.6.3 Response of a CTLTI system to periodic input signal
4.7 CTLTI Systems with Non-Periodic Input Signals
4.8 Further Reading
MATLAB Exercises
Computing finite-harmonic approximation to pulse train
Computing multiple approximations to pulse train
Graphing the line spectrum in Example 4.5
Line spectrum for Example 4.6
Graphing system function for RC circuit
Problems
MATLAB Problems
MATLAB Projects
Chapter 5 - Fourier Analysis for Discrete-Time Signals and Systems
Chapter Objectives
5.1 Introduction
5.2 Analysis of Periodic Discrete-Time Signals
5.2.1 Discrete-Time Fourier Series (DTFS)
5.2.2 Properties of the DTFS
5.3 Analysis of Non-Periodic Discrete-Time Signals
5.3.1 Discrete-time Fourier transform (DTFT)
5.3.2 Developing further insight
5.3.3 Existence of the DTFT
5.3.4 DTFT of some signals
5.3.5 Properties of the DTFT
5.3.6 Applying DTFT to periodic signals
5.4 Energy and Power in the Frequency Domain
5.4.1 Parseval’s theorem
5.4.2 Energy and power spectral density
5.4.3 Autocorrelation
5.5 System Function Concept
5.6 DTLTI Systems with Periodic Input Signals
5.6.1 Response of a DTLTI system to complex exponential signal
5.6.2 Response of a DTLTI system to sinusoidal signal
5.6.3 Response of a DTLTI system to periodic input signal
5.7 DTLTI Systems with Non-Periodic Input Signals
5.8 Discrete Fourier Transform
5.8.1 Relationship of the DFT to the DTFT
5.8.2 Zero padding
5.8.3 Properties of the DFT
5.8.4 Using the DFT to approximate the EFS coefficients
5.8.5 Using the DFT to approximate the continuous Fourier transform
5.9 Further Reading
MATLAB Exercises
Developing functions to implement DTFS analysis and synthesis
Testing DTFS functions
Developing and testing a function to implement periodic convolution
Steady-state response of DTLTI system to sinusoidal input
Exploring the relationship between the DFT and the DTFT
Using the DFT to approximate the DTFT
Developing functions for circular time shifting and time reversal
Computing conjugate symmetric and antisymmetric components
Using the symmetry properties of the DFT
Circular and linear convolution using the DFT
Developing a convolution function using the DFT
Exponential Fourier series approximation using the DFT
Testing the EFS approximation function
Fourier transform approximation using DFT
Problems
MATLAB Problems
MATLAB Projects
Chapter 6 - Sampling and Reconstruction
Chapter Objectives
6.1 Introduction
6.2 Sampling of a Continuous-Time Signal
6.2.1 Nyquist sampling criterion
6.2.2 DTFT of sampled signal
6.2.3 Sampling of sinusoidal signals
6.2.4 Practical issues in sampling
6.3 Reconstruction of a Signal From Its Sampled Version
6.4 Resampling Discrete-Time Signals
6.4.1 Reducing the sampling rate by an integer factor
6.4.2 Increasing the sampling rate by an integer factor
6.5 Further Reading
MATLAB Exercises
Spectral relations in impulse sampling
DTFT of discrete-time signal obtained through sampling
Sampling a sinusoidal signal
Natural sampling
Zero-order hold sampling
Graphing signals for natural and zero-order hold sampling
Reconstruction of right-sided exponential
Frequency spectrum of reconstructed signal
Resampling discrete-time signals
Problems
MATLAB Problems
MATLAB Projects
Chapter 7 - Laplace Transform for Continuous-Time Signals and Systems
Chapter Objectives
7.1 Introduction
7.2 Characteristics of the Region of Convergence
7.3 Properties of the Laplace Transform
7.3.1 Linearity
7.3.2 Time shifting
7.3.3 Shifting in the s-domain
7.3.4 Scaling in time and s- domains
7.3.5 Differentiation in the time domain
7.3.6 Differentiation in the s-domain
7.3.7 Convolution property
7.3.8 Integration property
7.4 Inverse Laplace Transform
7.4.1 Partial fraction expansion with simple poles
7.4.2 Partial fraction expansion with multiple poles
7.5 Using the Laplace Transform with CTLTI Systems
7.5.1 Relating the system function to the differential equation
7.5.2 Response of a CTLTI system to a complex exponential signal
7.5.3 Response of a CTLTI system to an exponentially damped sinusoid
7.5.4 Pole-zero plot for a system function
7.5.5 Graphical interpretation of the pole-zero plot
7.5.6 System function and causality
7.5.7 System function and stability
7.5.8 All-pass systems
7.5.9 Inverse systems
7.5.10 Bode plots
7.6 Simulation Structures for CTLTI Systems
7.6.1 Direct-form implementation
7.6.2 Cascade and parallel forms
7.7 Unilateral Laplace Transform
7.7.1 Time shifting
7.7.2 Differentiation in time
7.7.3 Initial and final value theorems
7.8 Further Reading
MATLAB Exercises
Three dimensional plot of Laplace transform
Computing the Fourier transform from the Laplace transform
Graphing poles and zeros
Residue calculations
Symbolic calculations for Laplace transform
Computing frequency response of a system from pole-zero layout
Frequency response from pole-zero layout revisited
System objects
Bode plots
Solving a differential equation through Laplace transform
Problems
MATLAB Problems
MATLAB Projects
Chapter 8 - z-Transform for Discrete-Time Signals and Systems
Chapter Objectives
8.1 Introduction
8.2 Characteristics of the Region of Convergence
8.3 Properties of the z-Transform
8.3.1 Linearity
8.3.2 Time shifting
8.3.3 Time reversal
8.3.4 Multiplication by an exponential signal
8.3.5 Differentiation in the z-domain
8.3.6 Convolution property
8.3.7 Initial value
8.3.8 Correlation property
8.3.9 Summation property
8.4 Inverse z-Transform
8.4.1 Inversion integral
8.4.2 Partial fraction expansion
8.4.3 Long division
8.5 Using the z-Transform with DTLTI Systems
8.5.1 Relating the system function to the difference equation
8.5.2 Response of a DTLTI system to complex exponential signal
8.5.3 Response of a DTLTI system to exponentially damped sinusoid
8.5.4 Graphical interpretation of the pole-zero plot
8.5.5 System function and causality
8.5.6 System function and stability
8.5.7 Allpass systems
8.5.8 Inverse systems
8.6 Implementation Structures for DTLTI Systems
8.6.1 Direct-form implementations
8.6.2 Cascade and parallel forms
8.7 Unilateral z-Transform
8.8 Further Reading
MATLAB Exercises
Three-dimensional plot of z-transform
Computing the DTFT from the z-transform
Graphing poles and zeros
Using convolution function for polynomial multiplication
Partial fraction expansion with MATLAB
Developing a function for long division
Computing frequency response of a system from pole-zero layout
Frequency response from pole-zero layout revisited
Preliminary calculations for a cascade-form block diagram
Preliminary calculations for a cascade-form block diagram revisited
Preliminary calculations for a parallel-form block diagram
Implementing a system using second-order sections
Solving a difference equation through z-transform
Problems
MATLAB Problems
MATLAB Projects
Chapter 9 - State-Space Analysis of Systems
Chapter Objectives
9.1 Introduction
9.2 State-Space Modeling of Continuous-Time Systems
9.2.1 State-space models for CTLTI systems
9.2.2 Obtaining state-space model from physical description
9.2.3 Obtaining state-space model from differential equation
9.2.4 Obtaining state-space model from system function
9.2.5 Alternative state-space models
9.2.6 CTLTI systems with multiple inputs and/or outputs
9.2.7 Solution of state-space model
9.2.8 Computation of the state transition matrix
9.2.9 Obtaining system function from state-space model
9.3 State-Space Modeling of Discrete-Time Systems
9.3.1 State-space models for DTLTI systems
9.3.2 Obtaining state-space model from difference equation
9.3.3 Obtaining state-space model from system function
9.3.4 Solution of state-space model
9.3.5 Obtaining system function from state-space model
9.4 Discretization of Continuous-Time State-Space Model
9.5 Further Reading
MATLAB Exercises
Obtaining state-space model from system function
Diagonalizing the state matrix
Computation of the state transition matrix
Solving the homogeneous state equation
Symbolic computation of the state transition matrix
Obtaining system function from continuous-time state-space model
Obtaining system function from discrete-time state-space model
Discretization of state-space model
Discretization using Euler method
Problems
MATLAB Problems
Chapter 10 - Analysis and Design of Filters
Chapter Objectives
10.1 Introduction
10.2 Distortionless Transmission
10.3 Ideal Filters
10.4 Design of Analog Filters
10.4.1 Butterworth lowpass filters
10.4.2 Chebyshev lowpass filters
10.4.3 Inverse Chebyshev lowpass filters
10.4.4 Analog filter transformations
10.5 Design of Digital Filters
10.5.1 Design of IIR filters
10.5.2 Design of FIR filters
10.6 Further Reading
MATLAB Exercises
Butterworth analog filter design
Chebyshev polynomials
Chebyshev type-I analog filter design
Determining Chebyshev analog filter parameters
Chebyshev type-II analog filter design
Lowpass to highpass filter transformation
Lowpass to bandpass and lowpass to band-reject transformations
Impulse-invariant design
IIR filter design using bilinear transformation
IIR filter design using bilinear transformation revisited
A complete IIR filter design example
FIR filter design using Fourier series method
FIR filter design using Parks-McClellan technique
Problems
MATLAB Problems
MATLAB Projects
Chapter 11 - Amplitude Modulation
Chapter Objectives
11.1 Introduction
11.2 The Need for Modulation
11.3 Types of Modulation
11.4 Amplitude Modulation
11.4.1 Frequency spectrum of the AM signal
11.4.2 Power balance and modulation efficiency
11.4.3 Generation of AM signals
11.4.4 Demodulation of AM signals
11.5 Double-Sideband Suppressed Carrier Modulation
11.5.1 Frequency spectrum of the DSB-SC signal
11.6 Single-Sideband Modulation
11.7 Further Reading
MATLAB Exercises
Compute and graph the AM signal
EFS spectrum of the tone-modulated AM signal
Function to simulate a switching modulator
Testing the switching modulator
Function to simulate a square-law modulator
Testing the square-law modulator
Function to simulate envelope detector
Testing the envelope detector function
Problems
MATLAB Problems
MATLAB Projects
Appendices
A Complex Numbers and Euler’s Formula
A.1 Introduction
A.2 Arithmetic with Complex Numbers
A.2.1 Addition and subtraction
A.2.2 Multiplication and division
A.3 Euler’s Formula
B Mathematical Relations
B.1 Trigonometric Identities
B.2 Indefinite Integrals
B.3 Laplace Transform Pairs
B.4 z-Transform Pairs
C Closed Forms for Sums of Geometric Series
C.1 Infinite-Length Geometric Series
C.2 Finite-Length Geometric Series
C.3 Finite-Length Geometric Series (Alternative Form)
D Orthogonality of Basis Functions
D.1 Orthogonality for Trigonometric Fourier Series
D.2 Orthogonality for Exponential Fourier Series
D.3 Orthogonality for Discrete-Time Fourier Series
E Partial Fraction Expansion
E.1 Partial Fraction Expansion for Continuous-Time Signals and Systems
E.2 Partial Fraction Expansion for Discrete-Time Signals and Systems
F Review of Matrix Algebra