Digital Signal ProceSSing laboratory Second edition Digital Signal ProceSSing laBoratory Second edition B. Preetham Kumar MATLAB® is a trademark of The MathWorks, Inc. and is used with permission. The MathWorks does not warrant the accuracy of the text or exercises in this book.
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For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Visit the Taylor & Francis Web site at http://www.com and the CRC Press Web site at http://www.com To Veena and Vasanth and In memory of my parents Contents Preface. xiii Note to Readers on Structure of Book and Exercises.
xix 1 Introduction to Digital Signal Processing.1 Brief Theory of DSP Concepts.2 Applications of DSP.3 Discrete-Time Signals and Systems.4 DSP Software and Programming.5 DSP Hardware and Equipment.3 Digital Signal Processors. 20 2 Discrete-Time LTI Signals and Systems.1 Brief Theory of Discrete-Time Signals and Systems.2 Linear Constant Coefficient Difference Equation.2 Introduction to Z-Transforms and the System Function H(z).3 System Frequency Response H(ejω).4 Important Types of LTI Systems. 40 3 Time and Frequency Analysis of Communication Signals.1 Evolution of the Fourier Transform.2 Discrete-Time Fourier Transform (DTFT).3 Discrete Fourier Transform (DFT).5 The Fast Fourier Transform (FFT). 58 vii viii Contents 3.
62 4 Analog to Digital (A/D) and Digital to Analog (D/A) Conversion.1 Brief Theory of A/D Conversion.2 Pulse Code Modulation (PCM). 82 5 Digital Filter Design–I: Theory and Software Tools.1 Brief Theory of Digital Filter Design.2 Analog and Digital Filters.3 Analytical Design Techniques for FIR and IIR Digital Filters.1 Analytical Techniques for IIR Digital Filter Design.2 Analytical Techniques for FIR Filter Design.4 Computer Aided Design (CAD) Techniques for FIR and IIR Digital Filters.1 CAD of FIR Filters.2 CAD of IIR Filters.3 Conversion of Analog to Digital Filters.5 Digital Filter Structures.1 Generalized Filter Structures for IIR Systems.2 Generalized Filter Structures for FIR Systems. 112 6 Digital Filter Design–II: Applications.1 Applications of Digital Filtering.2 Brief Introduction to Digital Video Processing.1 Two-Dimensional Discrete Signals.2 Two-Dimensional Discrete Systems.3 Two-Dimensional Discrete-Time Fourier Transform (2-D DTFT).4 Two-Dimensional Discrete Fourier Transform (2-D DFT).5 Two-Dimensional Fast Fourier Transform (2-D FFT).6 Simulation of the Two-Dimensional Imaging Process. 130 Contents ix 7 DSP Hardware Design–I.1 Background of Digital Signal Processors (DSPs).1 Main Applications of DSPs.2 Types and Sources of DSP Chips.2 Evolution of Texas Instruments (TI) TMS320 DSP Chips.1 TMS320C6711 DSP Starter Kit (DSK).3 Software/Hardware Laboratory Using the TI TMS320C6711 DSK (or ‘C6711 DSK).1 Study and Testing of the Code Composer Studio (CCS).2 Experimenting the ‘C6711 DSK as a Signal Source.3 Experimenting the ‘C6711 DSK as a Real-Time Signal Source.4 Experimenting the ‘C6711 DSK as a Sine Wave Generator.5 Experimenting the ‘C6711 DSK for Math Operations.
170 8 DSP Hardware Design–II.1 Overview of Practical DSP Applications in Communication Engineering.2 Filtering Application to Extract Sinusoidal Signal from a Combination of Two Sinusoidal Signals.3 Filtering Application to Extract Sinusoidal Signal from a Noisy Signal.4 Comparative Study of Using Different Filters on Input Radio Receiver Signal. 190 Appendix A: Agilent Synthesized Function/Arbitrary Waveform Generators.3 Sinewave Spectral Purity.3 Operating Instructions of HP 3324A Synthesized Function/Sweep Generator. 199 Appendix B: Agilent RF Spectrum Analyzers. 208 Appendix C: Agilent Dynamic Signal Analyzers.2 Single Channel Amplitude.3 FFT Dynamic Range.6 Single Channel Phase.7 Cross-Channel Amplitude.8 Cross-Channel Phase.14 Computed Order Tracking—Option 1D0.15 Real-Time Octave Analysis—Option 1D1.16 Swept Sine Measurements—Option 1D2.17 Arbitrary Waveform Source—Option 1D4.1 Single Channel Mode Operation.2 Dual Channel Mode Operation.222 Appendix D: Agilent Digitizing Oscilloscopes.1 Acquisition: Analog Channels.2 Acquisition: Digital Channels (54621D, 54622D, 54641D, and 54642D Only).3 Vertical System: Analog Channels.4 Vertical System: Digital Channels (54621D, 54622D, 54641D, and 54642D Only).7 Analog Channel Triggering.
238 Appendix E: Texas Instruments DSPs and DSKs.1 Introduction to Digital Signal Processors (DSPs).1 Alternative Solutions to Digital Signal Processors.2 Texas Instruments DSP Product Tree.3 TMS320C6000™ Platform Overview Page.1 Code-Compatible Generations.3 C6000 Signal Processing Libraries and Peripheral Drivers.4 TMS320C6711 DSP Chip.5 TMS320C6711 Digital Signal Processing Starter Kit (DSK).1 Hardware and Software Components of the DSK.6 C Files for Practical Applications Using the ‘C6711 DSK.1 Signal Generation Applications Using the ‘C6711 DSK.2 Spectral Analysis Applications Using the ‘C6711 DSK.3 Digital Filtering Applications Using the ‘C6711 DSK. 260 xii Contents Appendix F: List of DSP Laboratory Equipment Manufacturers.1 Introduction to DSP Laboratory Equipment.3 Synthesized Signal Generators.4 Dynamic Signal Analyzers. 273 Preface The motivating factor in the preparation of this book was to develop a practical and readily understandable laboratory volume in Digital Signal Processing (DSP). The intended audience is primarily undergraduate and graduate students taking DSP for the first time as an elective course.
The book is very relevant at the present time, when software and hardware developments in DSP are very rapid, and it is vital for the students to complement theory with practical software and hardware applications in their curriculum. This book essentially evolved from the study material in two courses taught at the Department of Electrical and Electronic Engineering, California State University, Sacramento (CSUS). These courses, Introduction to Digital Signal Processing, and Digital Signal Processing Laboratory, have been offered at CSUS for the past several years. During these years of DSP theory and laboratory instruction for senior undergraduate and graduate students, often with varied subject backgrounds, we gained a great deal of experience and insight.
Students who took these courses gave very useful feedback, such as their interest for an integrated approach to DSP teaching that would be comprised of side-by-side training in both theory and practi- cal software/hardware aspects of DSP. In their opinion, the practical com- ponent of the DSP course curriculum greatly enhances the understanding of the basic theory and principles. The factors above guided us to prepare each chapter of this book to include the following components: a brief theory to explain the underlying math- ematics and principles, a problem solving section with a reasonable num- ber of problems to be worked by the student, a computer laboratory with programming examples and exercises in MATLAB® and Simulink®,* and finally, in applicable chapters, a hardware laboratory with exercises using test and measurement equipment, and the Texas Instruments TMS320C6711 DSP Starter Kit. In Chapter 1, we go into a brief theory of DSP applications and systems, with solved and unsolved examples, followed by a computer lab, which introduces the students to basic programming in MATLAB, and creation of system models in Simulink.
This chapter concludes with a hardware section, which contains instructions and exercises on usage of basic signal sources, such as synthesized sweep generators, and measuring equipment, such as oscilloscopes and spectrum analyzers. Chapter 2 is a more detailed description of LTI discrete-time signals and systems, and the mathematical tools used to describe these systems. Basic concepts such as z-transform, system function, discrete-time convolution, * MATLAB® and Simulink® are registered trademarks of The Mathworks, Inc. xiii xiv Preface and difference equations are reviewed in the theory section.
Practical types of LTI systems, such as inverse systems and minimum phase systems are also discussed, with example problems. This is followed by a computer lab, which has guidance and exercises in the creation and simulation of LTI system models. Chapter 3 covers the practical time and frequency analysis of discrete-time signals, with emphasis on the evolution of the Discrete Fourier Transform (DFT) and the Fast Fourier Transform (FFT). The software lab includes spec- tral analysis, using the FFT, of practical periodic and nonperiodic signals such as noisy signal generators and Amplitude Modulation (AM) systems.
The hardware lab involves actual measurement of harmonic distortion in signal generators, spectrum of AM signals, and the comparison of measured results with simulation from the computer lab section. Chapter 4 is a practical discussion of the Analog-to Digital (A/D) process, with an initial brief review of sampling, quantization (uniform and nonuniform), and binary encoding in the Pulse Code Modulation (PCM) process. The soft- ware lab includes MATLAB/Simulink A/D process simulation of practical audio signals, and advanced systems such as Differential PCM. The hardware lab gives guidance of the construction and testing of a FET Sample and Hold circuit.
Chapters 5 and 6 are devoted to design and application of digital filters. Chapter 5 reviews the basic concepts of digital filters, and analytical design techniques for Finite Impulse Response (FIR) and Infinite Impulse Response (IIR) digital filter design. The second edition also includes a section on FIR and IIR digital filter structures. The computer lab details Computer Aided Design (CAD) techniques for FIR and IIR digital filters, and has a series of rigorous exercises in usage of these techniques.
Chapter 6 deals with the application of digital filters to one-dimensional (audio) and two-dimensional (video) signals. The computer lab has a set of practical exercises in the appli- cation of one- and two-dimensional digital filters for practical purposes, such as audio recovery from noise, and image deblurring. Chapters 7 and 8 are focused on the application of practical DSP applica- tions through the Digital Signal Processor (DSP) hardware. The hardware used in this book is the Texas Instruments TMS320C6711 Digital Signal Processor Starter Kit.
Chapter 7 deals in detail with the organization and usage of the 6711 DSK, with a set of practical introductory exercises, such as signal generation and filtering. Chapter 8 is more applied and covers the hardware application and programming of the 6711 DSK for practical filter- ing applications of noise from audio signals. There are six appendices. The first four appendices give detailed hardware description and user instructions of the equipment used in this book.
The four equipment models covered are synthesized sweep generators, spec- trum analyzers, dynamic signal analyzers, and digitizing oscilloscopes in Appendices A, B, C, and D, respectively. Appendix E gives detailed schemat- ics, hardware description, and user instructions on the Texas Instruments 6711 DSK. Finally, Appendix F gives brief descriptions of alternate equipment Preface xv and manufacturers, who produce equipment with similar capabilities as the ones described in Appendices A through D. I would like to thank a number of people without whom this book could not have been completed.
First, I greatly appreciate the help of Stan Wakefield, publishing consultant, who initiated my contact with CRC Press.