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Digital Signal Processing in Communication Systems Digital Signal Processing in Communication Systems DIGITAL SIGNAL PROCESSING IN COMMUNICATION SYSTEMS DIGITAL SIGNAL PROCESSING IN COMMUNICATION SYSTEMS Marvin E. Frerking ~. SPRINGER SCIENCE+BUSINESS" MEDIA, LLC Library of Congress Cataloging-in-Publication Data Frerking, Marvin E. Digital signal processing in communication systems / Marvin E. Frerking. p. em. Includes index. ISBN 978-1-4419-4740-6 ISBN 978-1-4757-4990-8 (eBook) DOI 10.1007/978-1-4757-4990-8 1. Signal processing--Digital techniques. 2. Digital communications. I. Title. TK5102.9.F74 1993 93-25299 621.382'2--dc20 eIP Copyright © 1994 by Van Nostrand Reinhold Ninth Printing 2003 by Springer Science+Business Media New York Originally published by Kluwer Academic Publishers in 2003 All rights reserved. No part of this publication may be reproduced, stored in a retrlevaJ system or transmitted in any form or by any means, mechanical, photo-copying, recording, or otherwise, without the prior written permission of the publisher, Springer Science+ Business Media, LLC. This book is published with the understanding that it is providing information only and not rendering engineering services. Information was used from sources believed to be reliable, but neither the author nor publisher guarantees the accuracy of the information, and neither shall be held responsible for any damages resulting from the use of this information. Neither the author nor publisher assume liability for patent infringements, nor is any patent license implied. Printed on acid-free paper. Dedication This book is dedicated to my wife, Shirley, who encouraged and sup­ ported the work and generously gave of her time to type the manu­ script. The author would also like to thank Linda Frerking for the many hours she spent drawing illustrations. Contents Preface ..••.....•.•.•.....••...................•.....••.....•.•.xi Acknowledgment . • • . • . • . • . • • . • . • . .• xiii Symbols and Abbreviations ..••...•...............•.•...........•. xv 1. Introduction .............................•.....••..•...•..... 1 2. Digital Signal Processing Concepts ..•...•....•...•...•.........• 6 Signal Representations ......................................... 6 Fourier Series ............................................... II Fourier Transforms ........................................... 16 Discrete Fourier Transforms .................................... 27 Inverse Discrete Fourier Transforms ............................. 32 Fast Fourier Transforms ....................................... 33 Radix Four FFTs ............................................. 38 Sliding Discrete Fourier Transforms .............................. 42 Z-Transforms ............................................... 43 Digital Approximations of Analog Transfer Functions ............... 57 Impulse Invarient Method ...................................... 58 Bilinear Transforms .......................................... 61 Sample Rate Changes ......................................... 65 Problems ................................................... 67 3. Analog-to-Digital Conversion ....................•......•..... 72 Quantization Noise ........................................... 73 vii viii Digital Signal Processing in Communication Systems Intermodulation Distortion ..................................... 81 Sampling Time Related Distortions .............................. 82 Distortions Unique to Flash AID Converters ....................... 84 Successive Approximation AID Converters ........................ 86 Sample-and-Hold Circuits ...................................... 87 Digital-to-Analog Converter Distortions .......................... 90 Linearity Correction in AID Converters ........................... 93 Two-Stage AID Converters ..................................... 94 Sigma-Delta Modulators ....................................... 96 Charge Redistribution AID Converters ............................ 98 Performance Measurement .................................... 103 Sampling Narrowband Signals ................................. 107 Problems .................................................. 111 4. Processing Complex Signals .•.•.•...•••.•...•....•••.•..••... 113 Positive and Negative Frequencies .............................. 113 Complex Signals ............................................ 118 Frequency Translation ........................................ 124 Hilbert Transformers ......................................... 138 Problems .................................................. 148 5. Digital Filters ...........•...•....•.•......•.•••.....••...•• 152 Finite Impulse-Response Filters ................................ 153 Complex FIR Filters ......................................... 170 Frequency Translation in FIR Filters ............................ 171 Polyphase Filters ............................................ 174 Infinite Impulse-Response (IIR) Filters .......................... 182 Butterworth Filters .......................................... 183 Chebyshev Filters ........................................... 184 Elliptic Filters .............................................. 186 Filter Design ............................................... 187 Boxcar Filters .............................................. 193 Cascaded Integrator Comb Filters ............................... 199 Fast Convolution Filters ...................................... 202 Problems .................................................. 209 6. Digital Algorithms for Communication Systems •••••...••......• 212 Digital Frequency Sources .................................... 212 Modulation ................................................ 227 Amplitude Modulation Algorithms .............................. 229 Frequency Modulation ....................................... 243 FM Detection .............................................. 249 Threshold Extension Techniques-Phase Locked Loop ............. 257 Contents ix Single-Sideband Systems ..................................... 262 Audio Compressors .......................................... 286 Automatic Gain Control ...................................... 292 Squelch Circuits ............................................ 297 Problems .................................................. 299 7. Digital Receiver/Exciter Design . .............................. 305 Receiver Design Example ..................................... 307 Narrowband Receivers with High-Speed ND Converters ............ 342 Harmonic Sampling Receiver .................................. 353 Direct Sampling Receiver ..................................... 364 Radio Transmitters .......................................... 371 Detailed Exciter Design ...................................... 374 High-Efficiency Power Amplifiers .............................. 384 Problems .................................................. 389 8. Data Transmission ......................................... 392 Introduction ................................................. 392 Matched Filters ............................................. 398 Frequency Shift Keying ...................................... 410 Phase Shift Keying .......................................... 430 PSK Demodulation .......................................... 433 Quadrature Amplitude Modulation .............................. 459 Equalizers . ........ 464 Problems .................................................. 485 9. Speech Processing . ......................................... 490 Pulse Code Modulation ....................................... 492 Differential Pulse Code Modulation ............................. 494 Delta Modulation ........................................... 495 Continuously Variable Slope Delta Modulation .................... 497 Linear Predictive Coding ..................................... 498 Performance Evaluation ...................................... 526 Government Standard Algorithm: LPC-lO ........................ 527 Very Low Data Rate Speech Coding ............................ 532 Code Excited Linear Prediction (CELP) .......................... 539 Problems .................................................. 545 10. DSP Hardware . ............................................ 548 Digital Signal Processors ..................................... 549 Fast Fourier Transform Hardware ............................... 552 Interprocessor Communications ................................ 554 Multiplier Accumulators ...................................... 556 x Digital Signal Processing in Communication Systems Other DSP Chips ............................................ 559 Data Flow Structures ......................................... 560 Standard Bus Characteristics .................................. 562 Very High-Speed Parallel Buses ................................ 569 High-Speed Serial Data Exchange .............................. 571 Simulation and Testing ....................................... 572 Software Design ............................................ 574 Appendix A-Derivation of Aperture Jitter Effects . ................. 577 Appendix B-Derivation of Constants for IIR Oscillator ............. 581 Appendix C-Derivation of Equations for Function Table . ........... 585 Appendix D-Error Rate for Differentially Encoded Phase Shift Keying ......................................... 592 Appendix E-Derivation of Error Rate for Incoherent FSK Data Transmission ......................................... 597 Appendix F-Cordic Algorithm .................................. 600 Appendix G-Noise in a Sigma-Delta Modulator . ................... 604 References .
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