Digital and analog communication systemsPDF电子书下载

PREFACE 17

LIST OF SYMBOLS 21

1 INTRODUCTION 1

1-1 Historical Perspective 2

1-2 Digital and Analog Sources and Systems 5

1-3 Deterministic and Random Waveforms 6

1-4 Organization of the Book 6

1-5 Use of a Personal Computer and MATLAB 7

1-6 Block Diagram of a Communication System 8

1-7 Frequency Allocations 10

1-8 Propagation of Electromagnetic Waves 12

1-9 Information Measure 16

1-10 Channel Capacity and Ideal Communication Systems 18

1-11 Coding 19

Block Codes 20

Convolutional Codes 22

Code Imerleaving 25

Code Performance 25

Trellis-Coded Modulation 28

1-12 Preview 29

1-13 Study-Aid Examples 29

Ploblems 30

2 SIGNALS AND SPECTRA 33

2-1 Properties of Signals and Noise 33

Physically Reatizable Waveforms 34

Time Average Operator 35

De Vatue 36

Power 37

Rms Value and Normalized Power 39

Energy and Power Waveforms 40

Decibel 40

Phasors 42

2-2 Fourier Transform and Spectra 43

Definition 43

Properties of Fourier Transforms 46

Parseval s Theorem and Energy Spectral Density 48

Dirac Delta Function and Unit Step Function 51

Rectangular and Triangular-Pulses 54

Convolution 58

2-3 Power Spectral Density and Autocorrelation Function 61

Power Spectral Density 61

Autocorrelation Function 63

2-4 Orthogonal Series Representation of Signals and Noise 65

Orthogonal Functions 65

Orthogonal Series 67

2-5 Fourier Series 68

Complex Fourier Series 68

Quadrature Fourier Series 70

PolAr Fourier Series 71

Line Spectra for Periodic Waveforms 73

Power Spectral Density for Periodic Waveforms 77

2-6 Review of Linear Systems 79

Linear Time-Invariant Systems 79

Impulse Response 79

Transfer Function 80

Distortionless Transmission 83

Distortion of Audio,Videl,and Data Signals 84

2-7 Bandlimited Signals and Noise 86

Bandlimited Waveforms 86

Sampling Theorem 87

Impulse Sampling and Digital Signal Processing(DSP) 90

Dimensionality Theorem 93

2-8 Discrete Fourier Transform 94

Using the DFT to Compute the Continuous Fourier Transform 95

Using the DFT to Compute the Fourier Series 100

2-9 Bandwidth of Signals 101

2-10 Summary 110

2-11 Study-Aid Examples 110

Problems 115

3 BASEBAND PULSE AND DIGITAL SIGNALING 128

3-1 Introduction 128

3-2 Pulse Amplitude Modulation 129

Natural Sampling(Gating) 129

Instantaneous Sampling(Flat-Top PAM) 133

3-3 Pulse Code Modulation 137

Sampling,Quantizing,and Encoding 138

Practical PCM Circuits 138

Bandwidth of PCM Signals 142

Effects of Noise 143

Nonuniform Quantizing:μ-Law and A-Law Companding 147

V.90 56-kb/s PCM Computer Modem 151

3-4 Digital Signaling 152

Vector Representation 153

Bandwidth Estimation 155

Binary Signaling 156

Multilevel Signaling 158

3-5 Line Codes and Spectra 160

Binary Line Coding 160

Power Spectra for Binary Line Codes 163

Differential Coding 169

Eye Patterns 170

Regenerative Repeaters 171

Bit Synchronization 173

Power Spectra for Multilevel Polar NRZ Signals 176

Spectral Efficiency 179

3-6 Intersymbol Interference 180

Nyquist s First Method (Zero ISI) 182

Raised Cosine-Rolloff Nyquist Filtering 183

Nyquist s Second and Third Methods for Control of ISI 188

3-7 Differential Pulse Code Modulation 188

3-8 Delta Modulation 192

Granular Noise and Slope Overload Noise 194

Adaptive Delta Modulation and Continuously Variable Slope Delta Modulation 197

Speech Coding 199

3-9 Time-Division Multiplexing 199

Frame Synchronization 200

Synchronous and Asynchronous Lines 202

TDM Hierarchy 206

The TI PCM System 211

3-10 Packet Transmission System 213

3-11 Pulse Time Modulation:Pulse Width Modulation and Pulse Position Modulation 213

3-12 Summary 215

3-13 Study-Aid Examples 218

Problems 221

4 BANDPASS SIGNALING PRINCIPLES AND CIRCUITS 230

4-1 Complex Envelope Representation of Bandpass Waveforms 230

Definitions:Baseband,Bandpass,and Modulation 231

Complex Envelope Representation 231

4-2 Representation of Modulated Signals 233

4-3 Spectrum of Bandpass Signals 234

4-4 Evaluation of Power 237

4-5 Bandpass Filtering and Linear Distortion 240

Equivalem Low-Pass Filter 240

Linear Distortion 242

4-6 Bandpass Sampling Theorem 244

4-7 Received Signal Plus Noise 245

4-8 Classification of Filters and Amplifiers 246

Filters 246

Amplifiers 250

4-9 Nonlinear Distortion 251

4-10 Limiters 256

4-11 Mixers,Up Converters,and Down Converters 257

4-12 Frequency Multipliers 263

4-13 Detector Circuits 265

Envelope Detector 265

Product Detector 266

Frequency Modulation Detector 268

4-14 Phase-Locked Loops and Frequency Synthesizers 273

4-15 Direct Digital Synthesis 281

4-16 Transmitters and Receivers 281

Generalized Transmitlers 281

Generalized Receiver:The Superheterodvne Receiver 283

Zero-IF Receivers 287

Inferference 288

4-17 Software Radios 288

4-18 Summary 289

4-19 Study-Aid Examples 289

Problems 295

5 AM,FM,AND DIGITAL MODULATED SYSTEMS 302

5-1 Amplitude Modulation 303

5-2 AM Broadcast Technical Standards 308

5-3 Double-Sideband Suppressed Carrier 309

5-4 Costas Loop and Squaring Loop 310

5-5 Asymmetric Sideband Signals 312

Single Sideband 312

Vestigial Sideband 316

5-6 Phase Modulation and Frequency Modulation 318

Representation of PM and FM signals 318

Spectra of Angle-Modulated Signals 323

Narrowband Angle Modulation 328

Wideband Frequency Modulation 329

Preemphasis and Deemphasis in Angle-Modulated Systems 333

5-7 Frequency-Division Multiplexing and FM Stereo 333

5-8 FM Broadcast Technical Standards 337

5-9 Binary Modulated Bandpass Signaling 337

On-Off Keying(OOK) 340

Binary-Phase-Shift Keying(BPSK) 343

Differential Phase-Shift Keying(DPSK) 344

Frequency-Shift Keying(FSK) 345

5-10 Multilevel Modulated Bandpass Signaling 352

Quadralure Phase-Shift Keying(QPSK) and M-ary Phase-Shift Keying(MPSK) 352

Quadrature Amplitude Modulation(QAM) 355

OQPSK and π/4 QPSK 356

PSD for MPSK,QAM,QPSK,OQPSK and π/4 QPSK 357

Spectral Efficiency for MPSK,QAM,QPSK,OQPSK,and π/4 QPSK with Raised Cosine Filtering 359

5-11 Minimum-Shift Keying(MSK) and GMSK 360

5-12 Orthogonal Frequency Division Multiplexing(OFDM) 365

5-13 Spread Spectrum Systems 370

Direct Sequence 371

Frequency Hopping 377

5-14 Summary 377

5-15 Study-Aid Examples 379

Problems 382

6 RANDOM PROCESSES AND SPECTRAL ANALYSIS 395

6-1 Some Basic Definitions 396

Random Processes 396

Stationarity and Ergodicity 397

Correlation Functions and Wide-Sense Stationarity 401

Complex Random Processes 403

6-2 Power Spectral Density 405

Definition 405

Wiener-Khintchine Theorem 406

Properties of the PSD 409

General Formula for the PSD of Digital Signals 413

White Noise Processes 416

Measurement of PSD 417

6-3 Dc and Rms Values for Ergodic Random Processes 418

6-4 Linear Systems 420

Input-Output Relationships 420

6-5 Bandwidth Measures 425

Equivalent Bandwidth 425

Rms Bandwidth 425

6-6 The Gaussian Random Process 427

Properties of Gaussian Processes 428

6-7 Bandpass Processes 431

Bandpass Representations 431

Properties of WSS Bandpass Processes 435

Proofs of Some Properties 439

6-8 Matched Filters 445

General Results 445

Results for Whits Noise 447

Correlation Processing 450

Transversal Matched Filter 452

6-9 Summary 455

6-10 Appendix:Proof of Schwarz s Inequality 457

6-11 Study-Aid Examples 459

Prblems 462

7 PERFORMANCE OF COMMUNICATION SYSTEMS CORRUPTED BY NOISE 472

7-1 Error Probabilities for Binary Signaling 473

General Results 473

Results for Gaussian Noise 475

Results for White Gaussian Noise and Matched-Filter Reception 477

Results for Colored Gaussian Noise and Matched-Filter Reception 478

7-2 Performance of Baseband Binary Systems 479

Unipolar Signaling 479

Polar Signaling 482

Bipolar Signaling 482

7-3 Coherent Detection of Bandpass Biary Signals 484

On-Off Keying 484

Binary-Phase-Shift Keying 486

Frequency-Shift Keying 487

7-4 Noncoherent Detection of Bandpass Binary Signals 490

On-Off Keying 490

Frequency-Shift Keying 494

Differential Phase-SDhift Keying 496

7-5 Quadrature Phase-Shift Keying and Minimum-Shift Keying 498

7-6 Comparison of Digital Signaling Systems 500

Bit Error Rate and Bandwidth 500

Symbol Error and Bit Error for Multilevel Signaling 502

Synchronization 503

7-7 Output Signal-to-Noise Ratio for PCM Systems 504

7-8 Output Signal-to-Noise Ratios for Analog Systems 510

Comparison with Baseband Systems 510

AM Systems with Product Detection 511

AM Systems with Envelope Detection 513

DSB-SC Systems 514

SSB Systems 515

PM Systems 515

FM Systems 519

FM Systems with Threshold Extension 522

FM Systems with Deemphasis 524

7-9 Comparison of Analog Signaling Systems 527

Ideal System Performance 527

7-10 Summary 530

7-11 Study-Aid Examples 530

Problems 539

8 WIRE AND WIRELESS COMMUNICATION SYSTEMS 547

8-1 The Explosive Growth of Telecommunications 547

8-2 Telephone Systems 548

Historical Basis 548

Modern Telephone Systems and Remote Terminals 549

8-3 Digital Subscriber Lines(DSL) 555

G.DMT and G.Lite Digital Subseriber Lines 556

Video On Demand(VOD) 558

Integrated Service Digital Network(ISDN) 558

8-4 Capacities of Public Switched Telephone Networks 561

8-5 Satellite Communication Systems 561

Digital and Analog Television Transmission 565

Data and Telephone Signal Multiple Access 567

Personal Communications via Stellite 573

8-6 Link Budget Analysis 575

Signal Power Received 575

Thermal Noise Sources 577

Characterization of Noise Sources 578

Noise Characterization of Linear Devices 579

Noise Characterization of Cascaded Linear Devices 585

Link Budget Evaluation 587

Eb/N0 Link Budget for Digital Systems 589

Path Loss for Urban Wireless Environments 590

8-7 Fiber Optic Systems 594

8-8 Cellular Telephone Systems 598

First Generation(1G)--The AMPS Analog System 599

Second Generation(2G)--The Digital Systems 602

The 1,900-MHz Band PCS Systems 605

Third Generation(3G)Systems 605

8-9 Television 606

Black-and-White Television 606

MTS Stereo Sound 613

Color Television 613

Standards for TV and CATV Systems 618

Digital TV(DTV) 622

8-10 Summary 627

8-11 Study-Aid Examples 628

Problems 632

APPENDIX A MATHEMATICAL TECHNIQUES,IDENTITIES,AND TABLES 639

A-1 Trigonometry and Complex Numbers 639

Definitions 639

Trigonometric Identities 639

A-2 Differential Calculus 640

Definition 640

Differentiation Rules 640

Derivative Table 640

A-3 Indeterminate Forms 641

A-4 Integral Calculus 641

Definition 641

Integration Techniques 642

A-5 Integral Tables 642

Indefinite Integrals 642

Definite Integrals 643

A-6 Series Expansions 644

Finite Series 644

Infinite Series 644

A-7 Hilbert Transform Pairs 645

A-8 The Dirac Delta Function 645

Properties of Dirac Delta Function 646

A-9 Tabulation of Sa(x)=(sin x)/x 647

A-10 Tabulation of Q(z) 648

APPENDIX B PROBABILITY AND RANDOM VARIABLES 650

B-1 Introduction 650

B-2 Sets 651

B-3 Probability and Relative Frequency 652

Simple Probability 652

Joint Probabitity 653

Conditional Probabilities 654

B-4 Random Variables 655

B-5 Cumulative Distribution Functions and Probability Density Functions 655

Properties of CDFs and PDFs 658

Diserete and Continuous Distributions 658

B-6 Ensemble Average and Moments 662

Ensemble Average 662

Moments 663

B-7 Examples of Important Distributions 665

Binomial Distribution 665

Poisson Distribution 668

Uniform Distribution 668

Gaussian Distribution 668

Sinusoidal Distribution 673

B-8 Functional Transformations of Random Variables 673

B-9 Multivariate Statistics 678

Multivariate CDFs and PDFs 678

Bivariate Statistics 680

Ganssian Bivariate Distribution 681

Multivariate Functional Transformation 682

Central Limit Theorem 684

Problems 686

APPENDIX C STANDARDS AND TERMINOLOGY FOR COMPUTER COMMUNICATIONS 692

C-1 Codes 692

Bandot 692

ASCII 692

C-2 DTE/DCE and Ethernet Interface Standards 693

Universal Serial Bus(USB) 695

RS-232D,RS-422A,RS-449,and RS-530 Interfaces 695

Centronics Parallel Interface 696

IEEE-488 Parallel Interface 697

Ethernet(IEEE 802.3)Interface 698

C-3 The ISO OSI Network Model 700

C-4 Data Link Control Protocols 703

TCP/IP 703

SDLC 703

HDLC 704

CCITT X.25 Protocol 704

Asynchronous Transfer Mode(ATM) 705

C-5 Modem Standards 706

APPENDIXD USING MATLAB 713

D-1 Quick Start for Running M-Files 713

D-2 Programming in MATLAB 714

REFERENCES 716

ANSWERS TO SELECTED PROBLEMS 729

INDEX 735