电子通信技术 英文影印版PDF电子书下载

1 Radio Frequency Amplifiers 1

Answers to Selected Problems 1

Appendices 1

Index 1

Appendix A Introducing the Impulse Function 2

Appendix B Filter Attenuation Curves 4

1-1 Impedance Review 5

Series Circuit Impedance 6

1-2 Series Resonance 7

1-3 Circuit Qand Bandwidth 8

1-4 Parallel Resonance 9

Appendix C Feedback Analysis for a Transconductance Amplifier 10

Appendix D Derivation of Frequency Response for PLLs 12

Nonideal Parallel Resonant Circuits 12

1-5 Small-Signal RF Amplifier Analysis 14

Gain in Decibels 16

Appendix E Communications Software 16

1-6 Small-signal RF Amplifier Design 18

1-7 Coupling Tuned Circuits 22

Appendix F Abbreviations and Acronyms 22

1-8 Nonideal Transformer Coupling 25

Transformer Loading 28

Measuring the Coupling Coefficient 31

1-9 Double-Tuned Circuits 31

Introduction 35

1-10 Laplace Transforms 35

Use of the Table of Transform Pairs 39

Circuit Impedance and the Transfer Function 40

Problems 41

1-11 Computer Analysis 45

2 Oscillators 54

2-1 Hartley Oscillator Circuit Analysis 57

2-2 Colpitts Oscillator 60

2-3 Clapp Oscillator 63

2-4 Tuned-Input/Tuned-Output Oscillator 64

RC Phase-Shift Oscillator 65

2-5 Untuned Oscillators 65

Wien Bridge Oscillator 66

Astable Multivibrator 67

2-6 Oscillator Stability and Spectral Purity 68

Temperature Stability of Oscillators 69

Temperature Coefficient 69

2-7 Crystals and Crystal Oscillators 70

Improving the Frequency Stability of Oscillators 70

Crystal Cuts(Y,AT,and BT) 71

Crystal Oscillators 72

Equivalent Circuit,Impedance,and Q 72

Harmonic Operation 75

2-8 Pierce Crystal Oscillator 75

Problems 76

2-9 Computer Analysis 80

3 Signal Spectra 83

3-1 Fourier Series and Signal Analysis 84

Even and Odd Functions 86

Fourier Series:Complex Exponential Form 90

Fourier Series of Other Waveforms 91

3-2 Fourier Transforms 94

3-3 Effect of Filters on Signals 97

3-4 Harmonic and Phase Distortion 100

Total Harmonic Distortion 101

3-5 Nondeterministic Signals 101

Problems 102

3-6 Computer Analysis 105

4 Elements of Noise 111

4-1 System Noise Sources 112

Thermal Noise 112

Shot Noise 113

Burst Noise 114

Flicker(1/f)Noise 114

4-2 Noise Spectral Density and Circuit Calculations 115

4-4 System Noise Figure 119

4-3 Noise and Feedback 119

4-5 Noise Temperature 120

4-6 Noise Bandwidth 121

4-7 Correlation and Noise 123

Problems 127

4-8 Computer Analysis 129

5 Modulation and Amplitude-Modulation Systems 133

5-1 Communications Systems 134

5-2 Voice Transmission and Multiplexing 135

5-3 Modulation 136

Amplitude Modulation 136

Modulation Index 137

5-4 AM Spectrum and Bandwidth 139

5-5 Power in an AM Signal 141

5-6 Nonsinusoidal Modulation Signals 142

5-7 AM Demodulation 144

Diagonal Clipping Distortion 146

Negative Peak Clipping 147

5-8 AM Receiver Systems 148

Superheterodyne Receiver Systems 148

5-9 Superheterodyne Receivers for AM 149

Choice of IF Frequency and Image Response 150

Detector Power Requirement 151

5-10 Receiver Gain and Sensitivity 151

5-11 Power Level in dBm and dBW 152

5-12 AGC and Dynamic Range 154

Delayed AGC 156

5-13 Receiver Noise 157

5-15 Derivation of the Noise Figure Equation 158

5-14 Signal-to-Noise Ratio(S/N) 158

5-16 Bandwidth Improvement 160

5-17 Bandwidth Narrowing 163

Problems 163

5-18 Computer Analysis 166

6 Transmitter Circuits 170

6-1 Power Amplifiers 171

Triode Vacuum Tube 172

Class C Power Amplifier 173

Power and Efficiency 176

6-2 Neutralization 177

6-3 Integrated Circuit,RF Power Amplifiers 178

6-4 Impedance-Matching Networks 184

Pi-Matching Network 187

Transistor and Vacuum-Tube Matching Network Equations 190

6-5 AM Modulator Circuits 193

Solid-State Modulator 193

Vacuum-Tube AM Modulator 194

Grid Modulation 196

Problems 197

6-6 Computer Analysis 201

7 Receiver Circuits 204

7-1 Low-Noise Amplifiers(LNAs) 205

Amplifier Dynamic Range 206

Third-Order Intercept Point 207

7-2 Mixers 208

General Nonlinearity 209

Other Frequency Converters 211

Switching or Sampling Mixers 211

Mixer Circuit Design 212

Mixing Modulated Signals 216

7-3 Tuning the Standard Broadcast Receiver 217

7-4 Filter Requirements for Interference Control and Selectivity 219

7-5 Filter Circuit Design 225

Determining the Filter Impedance Level 228

Low-Pass Filter Component Values 229

Bandpass Design 230

7-6 IF Amplifiers 234

7-7 AGC Circuits 240

7-8 The Audio System 244

Class B Push-Pull 244

7-9 Distortion and Feedback 247

Voltage-Sampled Shunt Feedback 250

Voltage-Sampled Series Feedback 251

Frequency Effects and Stability with Feedback 253

Problems 258

Appendix 7A:Class A Power Amplifier Design Example 263

7-10 Computer Analysis 265

8 Sideband Systems 283

8-1 Vestigial Sideband 284

8-2 Double Sideband/Suppressed Carrier 285

8-3 Balanced Modulator 286

8-4 Product Detector 293

The Sideband-Filter Method 294

8-6 Single Sideband/Suppressed Carrier 294

The Phase Method of SSB-SC Generation 296

Single-Sideband Receiver 298

8-7 Frequency-Division Multiplexing in Telephone Systems 301

8-8 Quadrature Multiplexing 304

Problems 308

8-10 Computer Analysis 310

9 Frequency and Phase Modulation 312

9-1 Frequency Modulation 312

Modulation Index 313

Sidebands and Spectrum 316

Wideband FM 318

Information Bandwidth and Power 321

9-2 Phase Modulation 323

Diode Modulator for PM 324

Derivation of Modulator Equations 327

Determining the Limits of Linearity 330

Wideband PM 331

9-3 Advantages of PM over FM 332

Demodulation of PM 332

9-4 FM Transmitter Circuits 333

Voltage-Controlled Oscillators(VCOs) 334

Integrated Circuit VCO 336

FM from PM 342

Reactance Modulator for FM 343

Reactance Modulator Sensitivity 344

Frequency Multipliers 345

9-5 Frequency Stability and AFC 346

FM Demodulators 351

PLL Demodulator 351

9-6 FM Receivers 351

Slope Detection/FM Discriminator 352

Foster-Seeley Phase-Shift Discriminator 354

Ratio Detector 357

Quadrature FM Detectors 358

IF Amplifiers and Limiters 360

9-7 Noise Performance 364

Preemphasis for FM 366

9-8 Stereo FM 367

Problems 370

9-9 Computer Analysis 374

10 Phase-Locked Loops 381

10-1 Loop Components 383

The Phase Detector 383

Phase Detector Gain 385

Digital Phase(Timing)Comparators 387

Amplifiers 387

Voltage-Controlled Oscillator(VCO) 388

10-2 Basic Loop Behavior 389

Locking the Loop 389

Acquisition 389

Locked Loop:The Tracking Mode 390

Loop Gain and Static Phase Error 390

Hold-In Range 391

Frequency Response of Individual Loop Components 393

10-3 Loop Frequency Response and Bandwidth 393

8-5 Phase Distortion in the Demodulation of Suppressed-Carrier Systems 393

PLL System Response 395

Closed-Loop Frequency Response and Bandwidth 397

10-4 FM and FSK Applications of PLLs 399

10-5 Noise 400

10-6 Improving Loop Response 401

Determining Loop Stability and Dynamic Behavior Using the Bode Plot 402

Phase Margin 403

Damping and Undamped Natural Frequency 405

Rise in Loop Frequency Response 407

Switching and Settling Time 409

Lead-Lag Compensation 410

10-7 Phase-Locked Loop Compensation 410

Direct Frequency Synthesizers 417

10-8 Frequency Synthesizers 417

Phase-Locked Synthesizers 419

Translation Loops and Multiple-Loop Synthesizers 422

10-9 Coherent Receivers:Phase-Locked Loop,Acquisition,and Pull-In Frequency Range 431

Problems 434

10-10 Computer Analysis 439

11 Pulse and Digital Modulation 443

11-1 Sampled Data and the Sampling Theorem 444

11-2 Pulse Amplitude Modulation--Natural and Flat-Top Sampling 447

Time-Division Multiplexing 449

Intersymbol Interference(ISI) 451

11-3 Pulse Width and Pulse Position Modulation(PWM ＆ PPM) 453

Demodulation 454

Pulse Code Modulation(PCM) 456

11-4 Digital Modulation 456

Multiplexing PCM Channels 457

Bandwidth Requirements 458

Delta Modulation(DM) 459

11-5 Quantization Noise 466

11-6 Qualitative Comparisons of Pulse and Digital Modulation Systems 467

Problems 467

11-7 Computer Analysis 470

12 Digital Communication Concepts 472

12-1 Digital Information 473

Coding 473

Coding Efficiency 474

12-2 Information Transfer Rate 474

12-3 Signaling(Baud)Rate 475

12-4 System Capacity 477

12-5 Bandwidth Considerations 480

Minimum Possible Bandwidth 480

Digital Transmission Formats 483

Pulse Shaping for Minimizing Bandwidth and Pulse Distortion 483

12-6 Power in Digital Signals 484

12-7 PCM System Analysis 486

Resolution and Dynamic Range 488

Digitizing/Encoding 488

Signal-to-Quantization Noise Ratio 491

Quantization Noise 491

Companding 492

Digital-to-Analog Converters(DACs) 496

12-8 PCM Telephone Circuitry 496

Analog-to-Digital(A/D)Converters 498

Telephone Dialing Tones—Synthesizing and Decoding 502

Codec 502

Problems 504

12-9 Computer Analysis 506

13 Data Communication Techniques 516

13-1 Standard Digital Codes 517

Codes and Error Control Techniques 520

Reed-Solomon Codes 522

13-2 Error Detection 525

Error Detecting and Correcting 527

13-3 Noise and Data Errors 532

13-4 Intercomputer Communications 535

13-5 Serial-Transmission Interfacing 536

UART for Asynchronous Communication 537

Cyclic Redundancy Checks 538

The 20-mA Loop—Teleprinters 540

EIA and CCITT Voltage Interfacing of Computer Devices 542

Frequency-Shift Key(FSK)Modems 546

13-6 Carrier Systems and Modems 546

Modems 546

Automatic Retransmission Request(ARQ) 547

A Full-Duplex,Two-Wire Line,FSK Modem 548

Continuous-Phase FSK and MSK 551

13-7 Synchronous Communication Techniques 552

Data Networks and Synchronous Transmission Protocols 553

Point-to-Point 553

Switched Networks—Synchronous Transmissions 554

Multipoint Lines 554

Packet Switching 554

Binary Synchronous Communications(Bisync) 557

Synchronous Protocols 557

Bit-Oriented Protocols:SDLC,HDLC,and X.25 559

13-8 Open System Interconnect and ISDN 562

Open System Interconnections(OSI) 562

Integrated Services Digital Network(ISDN) 563

Asynchronous Transfer Mode(ATM) 565

Problems 568

13-9 Computer Analysis 571

14 Transmission Lines and Waveguides 576

14-1 Transmission Lines 577

TEM Wave Propagation 578

Transients and Reflections 579

14-2 Sinusoidal Signals as Traveling Waves 585

Sinusoidal Signal Reflections and Standing Waves 586

Slotted Line and VSWR 588

14-3 The Smith Chart 589

14-4 Impedance-Matching Techniques 592

14-5 S-Parameters 595

14-6 Microstrip Amplifier Design 601

Microstrip Design 601

14-7 Waveguides 608

Waveguide Modes 609

Boundary Conditions 609

Coupling to Waveguides 612

Use of Smith Chart with Waveguide Transmissions 613

14-8 Directional Couplers 615

Problems 617

14-9 Computer Analysis 620

15 Antennas and Radiowave Propagation 625

15-1 Antenna Radiation 626

Polarization 627

Radiation Pattern and Power Density 628

15-3 Dipole(Hertz)Antenna 629

15-2 Received Power and Electric Field Strength 629

15-4 Directivity,Gain,and Aperture 630

Antenna Gain(dBi) 630

15-6 The Grounded Vertical(Marconi)Antenna 631

15-5 Beamwidth 631

Counterpoise 633

15-7 Television Antennas and Arrays 633

15-8 The Folded Dipole 634

Yagi-Uda 635

15-9 Turnstiles,Yagis,and Other Arrays 635

Log-Periodic Dipole Array 637

15-10 Loop Antennas 639

15-11 Parabolic Dish Antennas 640

Conical Horn Antennas 642

15-12 Wave Propagation Through Space 644

Refraction 644

Diffraction 645

HF Radio Waves 645

Long-Distance HF Radio Transmission 646

The Ionosphere 646

The Skip Zone 647

Multipath Distortion 648

15-13 Power Loss in Space 648

Free-Space Attenuation and Atmospheric Absorption 649

Fading and Fade Margin 650

Problems 651

15-14 Computer Analysis 653

16 Basic Television 656

16-1 Overview:Studio to Viewer 657

16-2 Frequency Allocations 658

16-3 TV Cameras 659

16-4 The Scan Raster and Synchronizing Signals 660

16-5 Video Bandwidth and Resolution 662

16-6 Transmitted Video and Audio Signals 662

16-7 Black-and-White TV Receivers 663

Tuner,Ifs,and Detectors 663

Gated AGC 663

Video Amplifiers and CRT Bias 666

Sync Separator 667

Vertical Deflection and Sync 668

Horizontal Deflection and CRT High Voltage 670

Phase-Locked Horizontal Sync 672

16-8 Color Television 674

Chroma Signals 675

Chroma I and Q Signals 676

Color TV Receiver Circuits 678

16-9 High-Definition Television 681

Video Compression Techniques 685

Problems 689

17 Digital Radio and Space Communication 691

Phase-Shift Key(PSK) 693

17-1 Modems and Digital Modulation Techniques 693

Demodulator 696

Differential PSK 697

Beyond Binary 698

QPSK 699

QPSK Demodulation 703

Quadrature Demodulation 703

Carrier Recovery 705

Bit Timing Recovery 706

Modems with Higher than Four-Level PSK and QAM 708

Quadrature Amplitude Modulation(QAM) 709

17-2 Noise and Error Rate Performance 710

Eb/NO 712

Bandwidth Requirements for Digital Radio 713

17-3 Space and Frequency Diversity 714

17-4 System Gain,Power,and Noise Budgets 715

Received Signal Power and System Gain 716

System Threshold 718

G/T 719

Satellite Systems 720

17-5 Satellite Access for Global Networking 720

Multiple-Access Techniques 723

Frequency-Division Multiple Access(FDMA) 724

TDMA 726

FDMA with DAMA 726

CDMA/Spread Spectrum 728

17-6 Spread Spectrum Systems 730

Direct-Sequence 731

Frequency-Hopping Spread Spectrum 735

17-7 Multiple Access Cellular Systems 737

Cellular Radio 738

Cellular Radio Propagation 741

Other Operational Considerations 743

Transmission of Digital Signals 744

Eb/No and Probability of Data Errors 747

17-8 Digital Modulation in Wireless Cellular and Personal Communication Systems 749

Intersymbol Interference(ISI) 750

Modulator/Demodulator Circuit Impairments 752

Minimum-Shift Key Modulation 754

π/4-DQPSK 756

17-9 RF Receiver and Transmitter System Considerations 760

Receivers 761

The Front End 763

Receiver Sensitivity 764

Image-Rejection Mixer 766

Local Oscillator Phase Noise 768

Reciprocal Mixing 770

Intermodulation Distortion and Dynamic Range 772

Transmitters 774

Modulation Phase/Amplitude Imbalance 776

Threshold and Coding Gain 779

17-10 RF Integrated Circuits and Transceivers for Digital Communications 780

AMPS and TDMA 786

Spread Spectrum WLAN 793

CDMA Transceiver 797

Digital Receiver 2000 799

Problems 802

8-9 Costas Loop for Suppressed-Carrier Demodulation 806

17-11 Computer Analysis 806

18 Fiber-Optic Communication 811

18-1 The Optical Fiber Communication Link 812

18-2 Light 813

Critical Angle and Reflections 814

18-3 Light Propagation in Glass Fibers 814

Numerical Aperture and Reflectance 815

Optical Fiber Waveguides 816

Bandwidth-Distance Product 818

Dispersion and Pulse Spreading 819

Maximum Allowable Data Rate 821

Fiber Power Losses 822

Communication LEDs 825

18-4 Transmitter Devices and Circuits 825

Injection Lasers 826

Direct Modulation Transmitters 827

External Modulators 829

Fiber Amplifiers and Dispersion-Shifted Fiber 830

18-5 Receiver Devices and Circuits 831

PIN Photodiodes 831

Photodiode Light Detectors 831

Receiver Circuits 832

Avalanche Photodiodes(APD) 832

Fiber Technology 834

18-6 Transmission Technology 834

Connectors,Splices,and Couplers 836

18-7 Fiber-Optic Data-Link Analysis 840

Analog Link Analysis 840

Bandwidth/Data Rate 844

Power Budget 846

International Networking 847

18-8 Fiber-Optic Communication Applications 847

Local Area Networking 848

Broadband RF Signals on CATV Fiber-Optic Links 852

Problems 855

18-9 Computer Analysis 859