本书除了包含基础理论和技术的相关内容外，力求充分反映卫星通信的最新技术、最新发展和最新成果。本书可供高等院校通信工程专业、电子信息专业本科生阅读，旨在带领学生了解和掌握卫星通信的相关知识以及卫星通信领域的新技术和新发展，引导学生学习卫星通信的兴趣。本书的编写工作得到了北京科技大学和国家自然科学基金项目的支持。

Contents Chapter 1 Introduction 1 1.1 A Brief History of Satellite Communications 1 1.1.1 International Activities 1 1.1.2 Domestic Activities 4 1.2 Characteristics of Satellite Communications 8 1.3 System Elements 10 1.3.1 Space Segment 11 1.3.2 Ground Segment 12 1.4 Satellite Elements 12 1.4.1 Communication Subsystem 13 1.4.2 Antennas Subsystem 15 1.4.3 Attitude and Orbit Control Subsystem 18 1.4.4 Telemetry, Tracking, Command and Monitoring Subsystem 20 1.4.5 Power Subsystem 23 1.5 Types of Satellite Orbit 24 1.5.1 Low Earth Orbit (LEO) 24 1.5.2 Medium Earth Orbit (MEO) 25 1.5.3 High Earth Orbit (HEO) 25 1.5.4 Geostationary Earth Orbit (GEO) 25 1.6 Use of Frequencies 25 1.7 Summary 26 References 26 Problems 27 Chapter 2 Orbital Mechanics 29 2.1 Orbital Theory 29 2.1.1 Equations of Satellite’s Orbit 29 2.1.2 Kepler’s Three Laws of Planetary Motion 34 2.1.3 Orbit of a Satellite 35 2.1.4 Determining the Satellite Location in the Orbit 37 2.1.5 Orbital Elements 39 2.2 Determining Look Angle 40 2.2.1 The Subsatellite Point 40 2.2.2 Elevation Angle Calculation 41 2.2.3 Azimuth Angle Calculation 43 2.2.4 Specialization to Geostationary Satellites 43 2.2.5 Visibility Test 44 2.3 Orbital Perturbations 44 2.3.1 Longitudinal Changes: Effects of the Earth’s Oblateness 45 2.3.2 Inclination Changes: Effects of the Sun and the Moon 46 2.4 Orbital Determination 48 2.5 Orbital Effects in Communications Systems Performance 48 2.5.1 Doppler Shift 48 2.5.2 Range Variations 49 2.6 Summary 49 References 50 Problems 50 Chapter 3 Earth Stations 54 3.1 Earth Station Elements 54 3.2 Site Selection and Layout of Earth Stations 55 3.2.1 Site Selection of Earth Stations 55 3.2.2 Layout of Earth Stations 58 3.3 Earth Stations and Ground Antennas 60 3.3.1 Antennas for Fixed Satellite Services 60 3.3.2 Antennas for Broadcast Satellite Services 63 3.3.3 Antennas for Mobile Satellite Services 63 3.3.4 Antennas for Store and Forward (Machine to Machine Service) 65 3.3.5 Antennas for TTC＆M 65 3.4 Summary 66 References 66 Chapter 4 Satellite Link Design 68 4.1 Introduction 68 4.2 Basic Transmission Theory 69 4.3 System Noise Temperature and G/T Ratio 72 4.3.1 Noise Temperature 72 4.3.2 Calculation of System Noise Temperatures 74 4.3.3 Noise Figure and Noise Temperature 76 4.3.4 G/T Ratio for Earth Stations 77 4.4 Link Design 78 4.4.1 Design of Downlinks 78 4.4.2 Design of Uplinks 80 4.5 Summary 84 References 84 Problems 84 Chapter 5 Modulation and Multiple Access 87 5.1 Introduction 87 5.2 Analogue Amplitude Modulation 88 5.3 Analogue Frequency Modulation 88 5.4 Digital Modulation 90 5.4.1 Filtering and Bandwidth Considerations 92 5.4.2 Binary Phase Shift Keying (BPSK) 95 5.4.3 Quadrature Phase Shift Keying ( QPSK) 98 5.4.4 Derivative PSK Modulation Schemes 100 5.5 Practical Satellite Modems 104 5.6 Multiple Access Methods 105 5.6.1 Network Architectures 106 5.6.2 Traffic Multiplexing 108 5.7 Multiple Access, and Assignment Strategies 110 5.7.1 Frequency Division Multiple Access (FDMA) 110 5.7.2 Time Division Multiple Access (TDMA) 114 5.8 Satellite-Switched TDMA and Onboard Processing 118 5.9 Spread Spectrum and Code Division Multiple Access (CDMA) 120 5.9.1 Spread Spectrum for Satellite Communications 120 5.9.2 Code Division Multiple Access (CDMA) 122 5.10 Packet Access Techniques 125 5.10.1 ALOHA Schemes 125 5.10.2 Enhancements to ALOHA 127 5.11 Hybrid Access Techniques, and Comparisons 128 5.12 Summary 129 References 130 Problems 130 Chapter 6 Error Control 135 6.1 Introduction 135 6.2 Channel Characteristics 135 6.2.1 Additive White Gaussian Noise (AWGN) 135 6.2.2 Doppler Effect 136 6.2.3 Multipath and Shadowing 136 6.2.4 Other Considerations 137 6.3 Channel Capacity 138 6.4 Coded Systems 140 6.4.1 Types of Code 141 6.4.2 Types of Channel 141 6.5 Error Detection Strategies 142 6.6 Implementation of Error Detection on Satellite Links 143 6.7 Forward Error Correction 145 6.8 Convolutional Codes 147 6.9 Binary Block Codes 149 6.10 Coding for Bursty Channels 150 6.11 Concatenation 151 6.12 Turbo Codes 153 6.13 Coding for Bandwidth-Limited Conditions 154 6.14 Application Considerations 155 6.15 Low-Density Parity-Check (LDPC) Codes 156 6.15.1 Decoding LDPC Codes 157 6.15.2 Encoding LDPC Codes 163 6.16 Luby Transform (LT) Codes 166 6.16.1 LT Encoding 167 6.16.2 LT Decoding 167 6.17 Raptor Codes 168 6.18 Spinal Codes 170 6.18.1 Encoding Spinal Codes 170 6.18.2 Decoding Spinal Codes 172 6.19 Summary 174 References 175 Problems 176 Chapter 7 Satellite Navigation and Positioning System 178 7.1 Introduction 178 7.2 Transit Navigation Satellite System 179 7.2.1 System Reliability and Availability 180 7.2.2 Constellation 181 7.2.3 Spacecraft 182 7.2.4 Ground System 182 7.3 GPS Navigation and Positioning System 183 7.3.1 GPS Signals 183 7.3.2 Modernized GPS 184 7.4 GLONASS Navigation and Positioning System 185 7.5 Galileo Navigation and Positioning System 187 7.5.1 Galileo Segment 187 7.5.2 Frequencies and Signals 188 7.5.3 Services 189 7.6 Beidou Navigation and Positioning System 190 7.7 Summary 193 References 194 Chapter 8 Satellite Emergency Communication System 195 8.1 Introduction 195 8.2 Characteristics and Construction Principles 195 8.2.1 Characteristics of Emergency Communication 196 8.2.2 Construction Principles 197 8.3 Communication System 197 8.3.1 Analysis of Satellite Emergency Communication System 198 8.3.2 Selection of Satellite Emergency Communication System 200 8.4 Disaster Management and Response 201 8.4.1 Disaster Management Cycle 201 8.4.2 Disaster Response 202 8.5 Disaster Management and Information and Communication Technology 203 8.6 Satellite-Assisted Disaster Management 204 8.7 Emergency Information Dissemination: Systems and Protocols 204 8.7.1 Examples of Existing Alerting Systems 205 8.7.2 Satcom/Satnav Systems for Emergency Information Delivery 205 8.7.3 Message Format for Exchanging Emergency Alerts 206 8.7.4 Alert Message Transmission Protocols 206 8.7.5 Satellite Systems and Protocols Comparison 207 8.8 Summary 208 References 209

王丽娜，博士，哈尔滨工业大学通信与信息系统专业。指导的2015年国家级本科生科技创新项目《基于北斗导航和GSM的汽车防盗系统》获二等奖，指导的2015年国家级本科生科技创新项目《计算机博弈之西洋跳棋》获二等奖，2016年编写的《现代通信技术（第2版）》获北京科技大学“教材出版奖”。__eol__