Signals, and Receivers

Transcription

1 ENGINEERING SATELLITE-BASED NAVIGATION AND TIMING Global Navigation Satellite Systems, Signals, and Receivers John W. Betz IEEE IEEE PRESS Wiley

2 CONTENTS Preface Acknowledgments Useful Constants List of Acronyms and Abbreviations About the Author xv xvii xix xxi xxvii 1 INTRODUCTION Satnav Revolution Basic Principles of Satnav Satnav Attributes Book Structure and How to Use This Book More to Explore 14 Reference 15 PART I SYSTEM AND SIGNAL ENGINEERING 17 2 SATELLITE ORBITS AND CONSTELLATIONS Kepler's Laws Orbital Deviations from Ideal Constellations Useful Geometry Calculations Summary 35 Review Questions 35 References 36 3 SATNAV SIGNALS Signals, Signal Processing, and Spreading Modulations Effects of Doppler and of Ionospheric Propagation Satnav Signal Characteristics Satnav Signal Structure Summary 92 Review Questions 92 References 99 vii

3 viii CONTENTS 4 LINK BUDGETS Free-Space Path Loss Calculating Maximum and Minimum Specified Received Power in Signal Specifications Terrestrial Link Budgets Building Penetration and Foliage Losses Summary 119 Review Questions 119 References CORRELATOR OUTPUT SNR, EFFECTIVE C/N0, AND 1/ Channel Model and Ideal Receiver Processing Correlator Output SNR With No Interference Correlator Output SNR With Interference: Spectral Separation Coefficients and Processing Gain Effective C/N Interference-to-Signal Power Ratios and Effective C/N A Deeper Look at Spectral Separation Coefficients Multiple Access Interference and Aggregate Gain of a Constellation Summary 135 Review Questions 136 References ERROR SOURCES AND ERROR CHARACTERIZATION Sources of Error in Satnav Positioning and Timing Calculation Dilution of Precision and Error Measures Positioning Errors for Standalone and Differential Satnav Receivers Other Error Sources Summary 153 Review Questions 154 References 155 PART II SATNAV SYSTEM DESCRIPTIONS NAVSTAR GLOBAL POSITIONING SYSTEM GPS History and Plans GPS Description GPS Signals 168

4 CONTENTS '* 7.4 Summary 196 Review Questions 197 References SATELLITE-BASED AUGMENTATION SYSTEMS SBAS History and Plans SBAS Description SBAS Signals Summary 209 Review Questions 210 References GLONASS GLONASS History and Plans GLONASS Description GLONASS Signals Summary 222 Review Questions 224 References GALILEO Galileo History and Plans Galileo Description Galileo Signals Summary 248 Review Questions 249 References BEIDOU SYSTEM BDS History and Plans BDS Description BDS Signals Summary 262 Review Questions 264 References QUASI-ZENITH SATELLITE SYSTEM QZSS History and Plans QZSS Description 268

5 X CONTENTS 12.3 QZSS Signals Summary 280 References INDIAN REGIONAL SATELLITE SYSTEM IRNSS History and Plans IRNSS Description IRNSS Signals Summary 289 References 289 PART III RECEIVER PROCESSING RECEIVER FRONT END Front-End Components Front-End Noise Figure Front-End Architectures and Frequency Plans Summary 328 Review Questions 329 References ANALOG-TO-DIGITAL CONVERSION Introduction to Analog-to-Digital Conversion and Automatic Gain Control Linear Analog-to-Digital Conversion Precorrelator Analog-to-Digital Conversion The Digitizing Correlator Summary 362 Review Questions 362 References ACQUISITION Initial Conditions for Acquisition Initial Synchronization Basics Initial Synchronization Computation Initial Synchronization Performance Other Aspects of Acquisition Summary 401

6 CONTENTS XI Review Questions 403 References DISCRETE-UPDATE TRACKING LOOPS Discrete-Update Tracking Loop Formulation Discrete-Update Tracking Loop Design Tracking Loop Characterization Summary 426 References CARRIER TRACKING AND DATA DEMODULATION Signal Processing for Carrier Tracking Frequency-Locked Loops Costas Loops Phase-Locked Loops Data Message Demodulation Summary 462 Review Questions 463 References CODE TRACKING Signal Processing for Code Tracking Discriminators for Code Tracking Carrier-Aided Code Tracking Code Tracking Performance in White Noise Code Tracking Performance in White Noise and Interference Ambiguous Code Tracking Summary 498 Appendix 19.A RMS Bandwidth 499 Review Questions 502 References POSITION, VELOCITY, AND TIME CALCULATION Forming Measurements Reducing Pseudorange Errors Standard Point Positioning Blending Solutions From Multiple Satnav Systems Velocity Calculation 522

7 xii CONTENTS 20.6 Working with Disadvantaged Receivers Precise Point Positioning Integrity Monitoring: Receiver Autonomous Integrity Monitoring and Fault Detection and Exclusion Summary 530 Review Questions 531 References 534 PART IV SPECIALIZED TOPICS INTERFERENCE Interference Characteristics Effects of Interference on Receiver Operation Dealing with Interference Summary 549 References MULTIPATH Multipath Characteristics Multipath Effects Multipath Mitigation Summary 567 References AUGMENTATIONS USING DIFFERENTIAL SATNAV Overview of Differential Satnav Code-Based Differential Systems Carrier-Based Differential Systems Summary 586 References ASSISTED SATNAV Reducing IFU and ITU Provision of Clock Corrections, Ephemeris, and Data Message Bits Block Processing Computing Pseudoranges and Position Summary 593 Reference 594

8 CONTENTS xiii 25 INTEGRATED RECEIVER PROCESSING Kalman Filter Overview Loosely and Tightly Coupled Sensor-Integrated Satnav Processing Standalone Vector Tracking Ultratightly Coupled Sensor-Integrated Satnav Processing Summary 606 References 607 A THEORETICAL FOUNDATIONS 609 A. 1 Some Useful Functions and Their Properties 610 A.2 Fourier Transforms 611 A.3 Signal Theory and Linear Systems Theory 611 A.4 Stochastic Processes 613 A.5 Some Results for Keyed Waveforms 615 A.6 Bandwidth Measures 619 A.7 Matrices and Matrix Algebra 621 A.8 Taylor Series and Linearization 623 A.9 Coordinate System Overview 624 References 625 Index 627