|
马上注册,结交更多好友,享用更多功能,让你轻松玩转社区。
您需要 登录 才可以下载或查看,没有账号?注册
x
本帖最后由 cjsb37 于 2013-4-29 09:09 编辑
Introduction.to.Digital.Signal.Processing.and.Filter.Design.Oct.2005<br>This preface is addressed to instructors as well as students at the junior–senior<br>level for the following reasons. I have been teaching courses on digital signal<br>processing, including its applications and digital filter design, at the undergraduate<br>and the graduate levels for more than 25 years. One common complaint I have<br>heard from undergraduate students in recent years is that there are not enough<br>numerical problems worked out in the chapters of the book prescribed for the<br>course. But some of the very well known textbooks on digital signal processing<br>have more problems than do a few of the books published in earlier years.<br>However, these books are written for students in the senior and graduate levels,<br>and hence the junior-level students find that there is too much of mathematical<br>theory in these books. They also have concerns about the advanced level of<br>problems found at the end of chapters. I have not found a textbook on digital<br>signal processing that meets these complaints and concerns from junior-level<br>students. So here is a book that I have written to meet the junior students’ needs<br>and written with a student-oriented approach, based on many years of teaching<br>courses at the junior level.<br>Network Analysis is an undergraduate textbook authored by my Ph.D. thesis<br>advisor Professor M. E. Van Valkenburg (published by Prentice-Hall in 1964),<br>which became a world-famous classic, not because it contained an abundance of<br>all topics in network analysis discussed with the rigor and beauty of mathematical<br>theory, but because it helped the students understand the basic ideas in their simplest<br>form when they took the first course on network analysis. I have been highly<br>influenced by that book, while writing this textbook for the first course on digital<br>signal processing that the students take. But I also have had to remember that the<br>generation of undergraduate students is different; the curriculum and the topic of<br>digital signal processing is also different. This textbook does not contain many of<br>the topics that are found in the senior–graduate-level textbooks mentioned above.<br>One of its main features is that it uses a very large number of numerical problems<br>as well as problems using functions from MATLAB® (MATLAB is a registered<br>trademark of The MathWorks, Inc.) and Signal Processing Toolbox, worked out<br>in every chapter, in order to highlight the fundamental concepts. These problems<br>are solved as examples after the theory is discussed or are worked out first<br>and the theory is then presented. Either way, the thrust of the approach is that<br>the students should understand the basic ideas, using the worked, out problems<br>as an instrument to achieve that goal. In some cases, the presentation is more<br>informal than in other cases. The students will find statements beginning with<br>“Note that. . .,” “Remember. . .,” or “It is pointed out,” and so on; they are meant<br>to emphasize the important concepts and the results stated in those sentences.<br>Many of the important results are mentioned more than once or summarized in<br>order to emphasize their significance.<br>The other attractive feature of this book is that all the problems given at the<br>end of the chapters are problems that can be solved by using only the material<br>discussed in the chapters, so that students would feel confident that they have an<br>understanding of the material covered in the course when they succeed in solving<br>the problems. Because of such considerations mentioned above, the author claims<br>that the book is written with a student-oriented approach. Yet, the students should<br>know that the ability to understand the solution to the problems is important but<br>understanding the theory behind them is far more important.<br>The following paragraphs are addressed to the instructors teaching a juniorlevel<br>course on digital signal processing. The first seven chapters cover welldefined<br>topics: (1) an introduction, (2) time-domain analysis and z-transform,<br>(3) frequency-domain analysis, (4) infinite impulse response filters, (5) finite<br>impulse response filters, (6) realization of structures, and (7) quantization filter<br>analysis. Chapter 8 discusses hardware design, and Chapter 9 covers MATLAB.<br>The book treats the mainstream topics in digital signal processing with a welldefined<br>focus on the fundamental concepts.<br>Most of the senior–graduate-level textbooks treat the theory of finite wordlength<br>in great detail, but the students get no help in analyzing the effect of finite wordlength<br>on the frequency response of a filter or designing a filter that meets a set<br>of frequency response specifications with a given wordlength and quantization<br>format. In Chapter 7, we discuss the use of a MATLAB tool known as the “FDA<br>Tool” to thoroughly investigate the effect of finite wordlength and different formats<br>of quantization. This is another attractive feature of the textbook, and the material<br>included in this chapter is not found in any other textbook published so far.<br>When the students have taken a course on digital signal processing, and join an<br>industry that designs digital signal processing (DSP) systems using commercially<br>available DSP chips, they have very little guidance on what they need to learn.<br>It is with that concern that additional material in Chapter 8 has been added,<br>leading them to the material that they have to learn in order to succeed in their<br>professional development. It is very brief but important material presented to<br>guide them in the right direction. The textbooks that are written on DSP hardly<br>provide any guidance on this matter, although there are quite a few books on<br>the hardware implementation of digital systems using commercially available<br>DSP chips. Only a few schools offer laboratory-oriented courses on the design<br>and testing of digital systems using such chips. Even the minimal amount of<br>information in Chapter 8 is not found in any other textbook that contains “digital<br>signal processing” in its title. However, Chapter 8 is not an exhaustive treatment<br>of hardware implementation but only as an introduction to what the students have<br>to learn when they begin a career in the industry.<br>Chapter 1 is devoted to discrete-time signals. It describes some applications<br>of digital signal processing and defines and, suggests several ways of describing<br>discrete-time signals. Examples of a few discrete-time signals and some basic<br>operations applied with them is followed by their properties. In particular,<br>the properties of complex exponential and sinusoidal discrete-time signals are<br>described. A brief history of analog and digital filter design is given. Then the<br>advantages of digital signal processing over continuous-time (analog) signal processing<br>is discussed in this chapter.<br>Chapter 2 is devoted to discrete-time systems. Several ways of modeling them<br>and four methods for obtaining the response of discrete-time systems when<br>excited by discrete-time signals are discussed in detail. The four methods are<br>(1) recursive algorithm, (2) convolution sum, (3) classical method, and (4) ztransform<br>method to find the total response in the time domain. The use of<br>z-transform theory to find the zero state response, zero input response, natural<br>and forced responses, and transient and steady-state responses is discussed in<br>great detail and illustrated with many numerical examples as well as the application<br>of MATLAB functions. Properties of discrete-time systems, unit pulse<br>response and transfer functions, stability theory, and the Jury–Marden test are<br>treated in this chapter. The amount of material on the time-domain analysis of<br>discrete-time systems is a lot more than that included in many other textbooks.<br>Chapter 3 concentrates on frequency-domain analysis. Derivation of sampling<br>theorem is followed by the derivation of the discrete-time Fourier transform<br>(DTFT) along with its importance in filter design. Several properties of<br>DTFT and examples of deriving the DTFT of typical discrete-time signals are<br>included with many numerical examples worked out to explain them. A large<br>number of problems solved by MATLAB functions are also added. This chapter<br>devoted to frequency-domain analysis is very different from those found in other<br>textbooks in many respects.<br>The design of infinite impulse response (IIR) filters is the main topic of<br>Chapter 4. The theory of approximation of analog filter functions, design of<br>analog filters that approximate specified frequency response, the use of impulseinvariant<br>transformation, and bilinear transformation are discussed in this chapter.<br>lenty of numerical examples are worked out, and the use of MATLAB functions<br>to design many more filters are included, to provide a hands-on experience to<br>the students.<br>Chapter 5 is concerned with the theory and design of finite impulse response<br>(FIR) filters. Properties of FIR filters with linear phase, and design of such filters<br>by the Fourier series method modified by window functions, is a major part of<br>this chapter. The design of equiripple FIR filters using the Remez exchange algorithm<br>is also discussed in this chapter. Many numerical examples and MATLAB<br>functions are used in this chapter to illustrate the design procedures.<br>After learning several methods for designing IIR and FIR filters from Chapters<br>4 and 5, the students need to obtain as many realization structures as possible,<br>to enable them to investigate the effects of finite wordlength on the frequency<br>response of these structures and to select the best structure. In Chapter 6, we<br>describe methods for deriving several structures for realizing FIR filters and IIR<br>filters. The structures for FIR filters describe the direct, cascade, and polyphase<br>forms and the lattice structure along with their transpose forms. The structures for<br>IIR filters include direct-form and cascade and parallel structures, lattice–ladder<br>structures with autoregressive (AR), moving-average (MA), and allpass structures<br>as special cases, and lattice-coupled allpass structures. Again, this chapter<br>contains a large number of examples worked out numerically and using the functions<br>from MATLAB and Signal Processing Toolbox; the material is more than<br>what is found in many other textbooks.<br>The effect of finite wordlength on the frequency response of filters realized<br>by the many structures discussed in Chapter 6 is treated in Chapter 7, and the<br>treatment is significantly different from that found in all other textbooks. There<br>is no theoretical analysis of finite wordlength effect in this chapter, because it<br>is beyond the scope of a junior-level course. I have chosen to illustrate the use<br>of a MATLAB tool called the “FDA Tool” for investigating these effects on the<br>different structures, different transfer functions, and different formats for quantizing<br>the values of filter coefficients. The additional choices such as truncation,<br>rounding, saturation, and scaling to find the optimum filter structure, besides the<br>alternative choices for the many structures, transfer functions, and so on, makes<br>this a more powerful tool than the theoretical results. Students would find experience<br>in using this tool far more useful than the theory in practical hardware<br>implementation.<br>Chapters 1–7 cover the core topics of digital signal processing. Chapter 8,<br>on hardware implementation of digital filters, briefly describes the simulation<br>of digital filters on Simulink®, and the generation of C code from Simulink<br>using Real-Time Workshop® (Simulink and Real-Time Workshop are registered<br>trademarks of The MathWorks, Inc.), generating assembly language code from the<br>C code, linking the separate sections of the assembly language code to generate an<br>executable object code under the Code Composer Studio from Texas Instruments<br>is outlined. Information on DSP Development Starter kits and simulator and<br>emulator boards is also included. Chapter 9, on MATLAB and Signal Processing<br>Toolbox, concludes the book.<br>The author suggests that the first three chapters, which discuss the basics of<br>digital signal processing, can be taught at the junior level in one quarter. The prerequisite<br>for taking this course is a junior-level course on linear, continuous-time<br>signals and systems that covers Laplace transform, Fourier transform, and Fourier<br>series in particular. Chapters 4–7, which discuss the design and implementation<br>of digital filters, can be taught in the next quarter or in the senior year as an<br>elective course depending on the curriculum of the department. Instructors must<br>use discretion in choosing the worked-out problems for discussion in the class,<br>noting that the real purpose of these problems is to help the students understand<br>the theory. There are a few topics that are either too advanced for a junior-level<br>course or take too much of class time. Examples of such topics are the derivation<br>of the objective function that is minimized by the Remez exchange algorithm, the<br>formulas for deriving the lattice–ladder realization, and the derivation of the fast<br>Fourier transform algorithm. It is my experience that students are interested only<br>in the use of MATLAB functions that implement these algorithms, and hence I<br>have deleted a theoretical exposition of the last two topics and also a description<br>of the optimization technique in the Remez exchange algorithm. However, I have<br>included many examples using the MATLAB functions to explain the subject<br>matter.<br>Solutions to the problems given at the end of chapters can be obtained by the instructors<br>from the Website <a href="http://www.wiley.com/WileyCDA/WileyTitle/" target="_blank">http://www.wiley.com/WileyCDA/WileyTitle/</a><br>productCd-0471464821.html. They have to access the solutions by clicking<br>“Download the software solutions manual link” displayed on the Webpage. The<br>author plans to add more problems and their solutions, posting them on theWebsite<br>frequently after the book is published.<br>As mentioned at the beginning of this preface, the book is written from my<br>own experience in teaching a junior-level course on digital signal processing.<br>I wish to thank Dr. M. D. Srinath, Southern Methodist University, Dallas, for<br>making a thorough review and constructive suggestions to improve the material<br>of this book. I also wish to thank my colleague Dr. A. K. Shaw, Wright State<br>University, Dayton. And I am most grateful to my wife Suman, who has spent<br>hundreds of lonely hours while I was writing this book. Without her patience<br>and support, I would not have even started on this project, let alone complete it.<br>So I dedicate this book to her and also to our family.<br>B. A. Shenoi<br>May 2005<br><br>管理员告知:该<span href="http://bbs.eetop.cn/tag.php?name=%D7%CA%C1%CF" class="t_tag">资料</span>之前已发布过了,请点击:<br>
<a href="viewthread.php?tid=3590&amp;highlight=Introduction%2Bto%2BDigital%2BSignal%2B" target="_blank">http://bbs.eetop.cn/viewthread.php?tid=3590&amp;highlight=Introduction%2Bto%2BDigital%2BSignal%2B</a><br><br>
|
|