部分目录:
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
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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