tailieunhanh - Understanding Digital Signal Processing

Top-Selling DSP Book for Seven Straight Years-Now Fully Updated! Understanding Digital Signal Processing, Third Edition,is quite simply the best resource for engineers and other technical professionals who want to master and apply today's latest DSP techniques. Richard G. Lyons has updated and expanded his best-selling second edition to reflect the newest technologies, building on the exceptionally readable coverage that made it the favorite of DSP professionals worldwide. | CHAPTER ONE Discrete Sequences and Systems Digital signal processing has never been more prevalent or easier to perform. It wasn t that long ago when the fast Fourier transform FFT a topic we ll discuss in Chapter 4 was a mysterious mathematical process used only in industrial research centers and universities. Now amazingly the FFT is readily available to US all. It s even a built-in function provided by inexpensive spreadsheet software for home computers. The availability of more sophisticated commercial signal processing software now allows us to analyze and develop complicated signal processing applications rapidly and reliably. We can now perform spectral analysis design digital filters develop voice recognition data communication and image compression processes using software that s interactive in both the way algorithms are defined and how the resulting data are graphically displayed. Since the mid-1980s the same integrated circuit technology that led to affordable home computers has produced powerful and inexpensive hardware development systems on which to implement our digital signal processing designs Regardless though of the ease with which these new digital signal processing development systems and software can be applied we still need a solid foundation in understanding the basics of digital signal processing. The purpose of this book is to build that foundation. In this chapter we ll set the stage for the topics we ll study throughout the remainder of this book by defining the terminology used in digital signal During a television interview in the early 1990s a leading computer scientist stated that had automobile technology made the same strides as the computer industry we d all have a car that would go a half million miles per hour and get a half million miles per gallon. The cost of that car would be so low that it would be cheaper to throw it away than pay for one day s parking in San Francisco. 1 2 Discrete Sequences and Systems processing .