Telecommunication Circuit Design - Second Edition

CONTENTS

Preface xiii

Chapter 1 The History ofTele communications 1

1.1 Introduction 1

1.2 Telecommunication Before the Electric Telegraph 1

1.3 The Electric Telegraph 2

1.4 The Facsimile Machine 4

1.5 The Telephone 6

1.6 Radio 8

1.7 Television 9

1.8 The Growth of Bandwidth and the Digital Revolution 10

1.9 The Internet 11

1.10 The World Wide Web 13

References 15

Bibliography 16

Chapter 2 Amplitude Modulated Radio Transmitter 17

2.1 Introduction 17

2.2 Amplitude Modulation Theory 18

2.3 System Design 21

2.3.1 Crystal-Controlled Oscillator 22

2.3.2 Frequency Multiplier 22

2.3.3 Amplitude Modulator 22

2.3.4 Audio Amplifier 22

2.3.5 Radio-Frequency Power Amplifier 23

2.3.6 Antenna 23

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2.4 Radio Transmitter Oscillator 23

2.4.1 Negative Conductance Oscillator 24

2.4.2 Classical Feedback Theory 26

2.4.3 Sinusoidal Oscillators 28

2.4.4 General Form of the Oscillator 28

2.4.5 Oscillator Design for Maximum Power Output 31

2.4.6 Crystal-Controlled Oscillator 35

2.5 Frequency Multiplier 37

2.5.1 Class-C Amplifier 40

2.5.2 Converting the Class-C Amplifier into a Frequency

Multiplier 40

2.6 Modulator 47

2.6.1 Square-law Modulator 47

2.6.2 Direct Amplitude Modulation Amplifier 49

2.6.3 Four-Quadrant Analog Multiplier 51

2.7 Audio-Frequency Amplifier 54

2.7.1 Basic Device Characteristics 54

2.7.2 Class-A Amplifier 55

2.7.3 Class-B Amplifier 60

2.8 The Radio-Frequency Amplifier 67

2.9 The Antenna 71

2.9.1 Radiation Pattern of an Isolated Dipole 72

2.9.2 Monopole or Half-Dipole 72

2.9.3 Field Patterns for a Vertical Grounded

Antenna 74

2.10 Classification of Amplitude Modulated Radio-Frequency

Bands 75

References 76

Problems 76

Chapter 3 The Amplitude Modulated Radio Receiver 79

3.1 Introduction 79

3.2 The Basic Receiver: System Design 79

3.3 The Superheterodyne Receiver: System Design 82

3.4 Components of the Superheterodyne Receiver 85

3.4.1 Receiver Antenna 85

3.4.2 Low-Power Radio-Frequency Amplifier 86

3.4.3 Frequency Changer or Mixer 90

3.4.4 Intermediate-Frequency Stage 99

3.4.5 Automatic Gain Control 101

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3.4.6 Demodulator 103

3.4.7 Audio-Frequency Amplifier 105

3.4.8 Loudspeaker 105

3.5 Short-Wave Radio 107

References 108

Bibliography 108

Problems 108

Chapter 4 Frequency Modulated Radio Transmitter 111

4.1 Introduction 111

4.2 Frequency Modulation Theory 111

4.3 The Parameter Variation Method 115

4.3.1 Basic System Design 115

4.3.2 Automatic Frequency Control of the FM

Generator 117

4.3.3 Component Design with Automatic Frequency

Control 118

4.4 The Armstrong System 122

4.4.1 Practical Realization 125

4.4.2 Component Circuit Design 127

4.5 Stereophonic FM Transmission 137

4.5.1 System Design 137

Bibliography 138

Problems 139

Chapter 5 The Frequency Modulated Radio Receiver 143

5.1 Introduction 143

5.2 Component Design 146

5.2.1 Antenna 146

5.2.2 Radio-Frequency Amplifier 146

5.2.3 Local Oscillator 147

5.2.4 Frequency Changer 147

5.2.5 Intermediate-Frequency Stage 147

5.2.6 Amplitude Limiter 148

5.2.7 Frequency Discriminator 148

5.3 Stereophonic Frequency Modulated Reception 156

5.3.1 Synchronous Demodulation 158

5.3.2 Stereophonic Receiver Circuit 158

References 158

Problems 159

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Chapter 6 The Television Transmitter 161

6.1 Introduction 161

6.2 System Design 162

6.3 Component Design 163

6.3.1 Camera Tube 163

6.3.2 Scanning System 167

6.3.3 Audio Frequency and FM Circuits 169

6.3.4 Video Amplifier 170

6.3.5 Radio-Frequency Circuits 179

6.3.6 Vestigial Sideband Filter 179

6.3.7 Antenna 179

6.3.8 Color Television 180

References 184

Bibliography 184

Problems 185

Chapter 7 The Television Receiver 187

7.1 Introduction 187

7.2 Component Design 189

7.2.1 Antenna 189

7.2.2 Superheterodyne Section 189

7.2.3 Intermediate-Frequency Amplifier 189

7.2.4 Video Detector 190

7.2.5 The Video Amplifier 191

7.2.6 The Audio Channel 191

7.2.7 Electron Beam Control Subsystem 191

7.2.8 Picture Tube 202

7.3 Color Television Receiver 203

7.3.1 Demodulation and Matrixing 203

7.3.2 Component Circuit Design 205

7.3.3 Color Picture Tube 207

7.4 High-Definition Television (HDTV) 209

Bibliography 210

Problems 210

Chapter 8 The Telephone Network 213

8.1 Introduction 213

8.2 Technical Organization 213

8.3 Basic Telephone Equipment 216

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8.3.1 Carbon Microphone 216

8.3.2 Moving-Iron Telephone Receiver 218

8.3.3 Local Battery – Central Power Supply 220

8.3.4 Signalling System 220

8.3.5 The Telephone Line 221

8.3.6 Performance Improvements 222

8.3.7 Telephone Component Variation 224

8.4 Electronic Telephone 224

8.4.1 Microphones 225

8.4.2 Receiver 225

8.4.3 Hybrid 226

8.4.4 Tone Ringer 229

8.4.5 Tone Dial 230

8.5 Digital Telephone 243

8.5.1 The Codec 244

8.6 The Central Office 253

8.6.1 Manual Office 253

8.6.2 Basics of Step-by-Step Switching 253

8.6.3 The Strowger Switch 256

8.6.4 Basics of Crossbar Switching 257

8.6.5 Central Office Tone Receiver 259

8.6.6 Elements of Electronic Switching 261

References 263

Problems 263

Chapter 9 Signal Processing in the Telephone System 267

9.1 Introduction 267

9.2 Frequency Division Multiplex (FDM) 267

9.2.1 Generation of Single-Sideband Signals 268

9.2.2 Design of Circuit Components 269

9.2.3 Formation of a Basic Group 269

9.2.4 Formation of a Basic Supergroup 270

9.2.5 Formation of a Basic Mastergroup 270

9.3 Time-Division Multiplex (TDM) 272

9.3.1 Pseudodigital Modulation 273

9.3.2 Pulse-Amplitude Modulation Encoder 273

9.3.3 Pulse-Amplitude Modulation Decoder 279

9.3.4 Pulse Code Modulation Encoder=Multiplexer 286

9.3.5 Pulse-Code Modulation Decoder=Demultiplexer 286

CONTENTS ix

9.3.6 Bell System T-1 PCM Carrier 286

9.3.7 Telecom Canada Digital Network 290

9.3.8 Synchronization Circuit 290

9.3.9 Regenerative Repeater 291

9.4 Data Transmission Circuits 295

9.4.1 Modem Circuits 298

References 300

Problems 301

Chapter 10 The Facsimile Machine 305

10.1 Introduction 305

10.2 Systems Design 307

10.2.1 The Transmit Mode 308

10.2.2 The Receive Mode 308

10.3 Operation 310

10.3.1 ‘‘Handshake’’ Protocol 310

10.4 The Transmit Mode 311

10.4.1 The CCD Image Sensor 311

10.4.2 The Binary Quantizer 315

10.4.3 The Two-Row Memory 317

10.5 Data Compression 318

10.5.1 The Modified Huffman (MH) Code 318

10.5.2 The Modified READ Code 318

10.6 The Modem 319

10.7 The Line Adjuster 319

10.8 The Receive Mode 319

10.8.1 The Power Amplifier 319

10.8.2 The Thermal Printer 321

10.9 Gray Scale Transmission: Dither Technique 322

References 323

Bibliography 323

Glossary 323

Problems 324

Chapter 11 Personal Wireless Communication Systems 325

11.1 Introduction 325

11.2 Modulation and Demodulation Revisited 326

11.3 Access Techniques 327

11.3.1 Multiplex and Demultiplex Revisited 327

11.3.2 Frequency-Division Multiple Access (FDMA) 328

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11.3.3 Time-Division Multiple Access (TDMA) 328

11.3.4 Spread Spectrum Techniques 329

11.4 Digital Carrier Systems 331

11.4.1 Binary Phase Shift Keying (BPSK) 333

11.4.2 Quadrature Phase Shift Keying (QPSK) 334

11.5 The Paging System 338

11.5.1 The POCSAG Paging System 338

11.5.2 Other Paging Systems 341

11.6 The Analog Cordless Telephone 343

11.6.1 System Design 343

11.6.2 Component Design 343

11.6.3 Disadvantages of the Analog Cordless

Telephone 347

11.7 The Cellular Telephone 347

11.7.1 System Overview 348

11.7.2 Advanced Mobile Phone System (AMPS) 348

11.8 Other Analog Cellular Telephone Systems 355

11.8.1 Disadvantages of Analog Cellular Telephone

Systems 357

11.9 The CDMA Cellular Telephone Systems 358

11.9.1 System Design of the Transmit Path 358

11.9.2 Component Circuit Design for the Transmit

Path 359

11.9.3 System Design of the Receive Path 361

11.9.4 Component Circuit Design for the Receive

Path 362

11.10 Other Digital Cellular Systems 362

References 363

Bibliography 363

Problems 364

Abbreviations 364

Chapter 12 Telecommunication Transmission Media 367

12.1 Introduction 367

12.2 Twisted-Pair Cable 367

12.2.1 Negative-Impedance Converter 370

12.2.2 Four-Wire Repeater 374

12.3 Coaxial Cable 375

12.4 Waveguides 376

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12.5 Optical Fiber 376

12.6 Free Space Propagation 377

12.6.1 Direct Wave 379

12.6.2 Earth-Reflected Wave 379

12.6.3 Troposphere-Reflected Wave 379

12.6.4 Sky-Reflected Wave 379

12.6.5 Surface Wave 380

12.7 Terrestrial Microwave Radio 380

12.7.1 Analog Radio 381

12.7.2 Digital Radio 384

12.8 Satellite Transmission System 384

References 389

Bibliography 389

Problems 390

Appendix A The Transformer 391

A.1 Introduction 391

A.2 The Ideal Transformer 392

A.3 The Practical Transformer 394

Appendix B Designation ofFre quencies 397

VHF Television Frequencies 397

UHF Television Frequencies 398

Appendix C The Electromagnetic Spectrum 399

Appendix D The Modified Huffman Data Compression Code 401

Appendix E Electronic Memory 405

E.1 Introduction 405

E.2 Basics of S-R Flip-Flop Circuits 405

E.3 The Clocked S-R Flip-Flop 407

E.4 Initialization of the S-R Flip-Flop 409

E.5 The Shift Register 409

E.5 Electronic Memory 411

E.6 Random Access Memory (RAM) 411

Appendix F Binary Coded Decimal to Seven-Segment

Decoder 415

Index 417

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