The main reason for the appearance of this tutorial is therapid development of modern telecommunication systems, aviation equipment and space systems of various functional purposes, as well as new information technologies, inextricably linked with the theory of building radio receivers.
Radio receivers are an integral part of a radio link, to a large extent determining the quality of its operation, both under normal operating conditions and in a difficult jamming environment. Since the creation of the first lightning detector A. S. Popov in 1895, the technique of radio receivers went a long way of development to modern automated digital systems.
The tutorial discusses the basics of building various types of amplifiers, most widely used in modern specialized radio receivers, as well as the principles ofbuilding digital radio receivers. At the same time, various types of amplifiers were considered, such as selective, low noise and transistor. The issues of building amplifiers in the book are closely linked with the problems of the best use of their resource.
Special attention in the textbook is paid to the known methods of providing the problem of automatic gain control for various systems. In this case, the systems of frequency and phase-locked loop were considered in linear and nonlinear modes of operation.
In practice, the circuits used to amplify signals are implemented taking into account the limitations imposed by the capabilities of the element base. In this case, individual practical solutions are based on the peculiarities of solving multicriteria problems, and not on the rigorous theory of synthesis of optimal signal reception circuits. Therefore, this book focuses on the analysis of processes occurring in the schemes of a known structure. At the same time, the authors tried to use a simple mathematical apparatus, based on the approaches ofharmonic analysis, giving preference to the physical visualization of the processes under consideration.
The textbook is based on the lectures given by the authors at the Saint Petersburg State University of Aerospace Instrumentation and at the Moscow State Technical University of Civil Aviation.

1 Technical Characteristics and Structural Diagrams of Radio Receiving Devices 1

1.1 General Information About Radio Receiving Devices 1

1.2 Interference with Radio Reception 3

1.3 Main Characteristics ofRadio Receivers 4

      1.3.1 Receiver Specifications 5

      1.3.2 Operational and Technical Characteristics of Receivers 8

1.4 Block Diagrams of Radio Receivers 8

References 11

2 Noise Ratio in Receivers 13

2.1 General Information on Fluctuation Noise in Receivers 13

2.2 Sources ofNoise in the Radio 16

      2.2.1 Resistor Noise 16

      2.2.2 Noise of Oscillatory Circuits 18

      2.2.3 Receiving Antenna Noise 19

      2.2.4 Noise of Active Elements of the Receiver 20

2.3 Noise Figure and Noise Temperature of a Linear Quadrupole 23

2.4 Noise Figure and Noise Temperature of a Multistage Circuit 27

2.5 Radio Sensitivity 28

References 30

3 Schemical Basics of Input Circuits and Selective Amplifiers 31

3.1 Purpose and Basic Characteristics of Input Circuits and Selective Amplifiers 31

3.2 Classification and Diagrams of Input Circuits and Selective Amplifiers 34

      3.2.1 Classification and Diagrams of Input Circuits of Various Ranges 34

      3.2.2 Classification and Circuits of Selective Amplifiers 39

      3.2.3 Lumped Selector Filters 43

3.3 Generalized Equivalent Circuit of the Selective Amplifier and the Input Circuit 49

References 53

4 Selective Amplifiers. Principles of Optimizing Their Parameters 55

4.1 Gain and Amplifier Selectivity Characteristic 55

4.2 Optimization of the Amplifier Gain 59

      4.2.1 Conditions for Obtaining the Maximum Gain of the Amplifier 59

      4.2.2 Features of Obtaining the Maximum Gain for a Given Bandwidth 62

4.3 Noise Figure of a Resonant Amplifier With an Input Circuit 65

4.4 Influence of Internal Feedback on the Properties of the Resonant Amplifier 69

      4.4.1 Brief Information About the Feedback in the Amplifier Stage 69

      4.4.2 Influence of the Internal Feedback of the Amplifier on Its Input Conductance 70

      4.4.3 Stability Factor and Stable Amplifier Gain 73

      4.4.4 Methods for Increasing the Stability of Selective Amplifiers 76

References 79

5 Multistage Single-Circuit Selective Amplifiers 81

5.1 Multistage Resonant Amplifier 81

5.2 Broadband Selective Amplifiers 84

      5.2.1 Amplifiers with Twos of Detuned Stages 84

      5.2.2 Amplifiers with Triplets ofDetuned Stages 86

      5.2.3 Comparative Assessment of Various Single-Loop Amplifier Circuits 88

5.3 Characteristics ofTransients in Linear Electoral Paths 89

5.4 Transients in Single-Loop Multistage Amplifiers 93

      5.4.1 Resonant Amplifier 93

      5.4.2 Amplifier with Pairs ofDetuned Stages 96

      5.4.3 Amplifier with Triplets ofDetuned Stages 101

References 103

6 Frequency Converters 105

6.1 General Information About Frequency Converters 105

6.2 Equivalent Circuit Parameters of the Frequency Converter 108

6.3 Transistor Frequency Converters 114

6.4 Diode Frequency Converters 119

References 126

7 Low-Noise Amplifiers 127

7.1 Regenerative Amplifiers 127

      7.1.1 General Information About Regenerative Amplifiers 127

      7.1.2 Regenerative Amplifier Gain 128

      7.1.3 Noise Characteristics ofRegenerative Amplifiers 131

7.2 Paramagnetic Amplifiers and Tunnel Diode Amplifiers 133

7.3 Parametric Amplifiers 134

      7.3.1 General Information About Parametric Amplifiers 134

      7.3.2 Circuits and Design Features of Parametric Amplifiers 136

      7.3.3 Gain of a Dual-Circuit Reflective Parametric Amplifier 139

      7.3.4 Noise Temperature of a Two-Terminal Reflective Parametric Amplifier 142

7.4 Transistor Amplifiers 148

7.5 Comparative Evaluation of Low-Noise Amplifiers 151

References 153

8 Radio Detectors 155

8.1 Principle of Operation and Main Characteristics of Amplitude Detectors 155

8.2 Diode Detectors. Detecting Strong Signals 158

8.3 Transistor Detectors of Amplitude-Modulated Signals 166

8.4 Pulse Signal Detectors 168

      8.4.1 Radio Pulse Diode Detectors 168

      8.4.2 Peak Pulse Detectors 171

8.5 Amplitude Limiters 173

8.6 Operating Principle and Basic Characteristics ofFrequency Detectors 176

8.7 Differential Frequency Detectors 178

8.8 Operating Principle and Basic Characteristics of Phase Detectors 186

8.9 Balance Phase Detector 188

References 191

9 Radio Adjustments 193

9.1 Purpose and Types ofRegulations 193

9.2 Main Structural Diagrams and Characteristics of Separate Elements of AFC Systems 195

9.3 Analysis of the Linear Operation of the Chap System 200

9.4 Operation of the Chap System at Large Distributions 204

9.5 Linear PLL Operation 207

9.6 PLL Operation at Large Distributions 209

9.7 General Information About AGC Systems 213

9.8 Structural Diagram of the AGC with Feedback and Characteristics of Its Separate Elements 216

9.9 Analysis of the AGC System with Feedback 220

References 224

10 Digital Radio Devices 227

10.1 General Information on Digital Radio Receivers 227

10.2 Analog-Digital Signal Conversion 229

10.3 Digital Filters 233

10.4 Digital Frequency Synthesizers 238

10.5 Digital Demodulators 240

10.6 Digital Systems of Automatic Regulations in the DRRD 245

References 249

机械工业信息研究院