A-GPS Assisted GPS- GNSS- and SBAS 国外原版数
For a listing of recent titles in the Artech House GNSS Technology and Applications library, turn to the back of this book A-GPS: Assisted gPs, gnss, and sbas Frank van tiggelen ARTECH HOUSE BOSTON LONDON artechhouse. com Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the U.S. Library of Congress British Library Cataloguing in Publication Data a catalog record for this book is available from the british library ISBN-13:978-1-59693-374-3 Cover design by igor valdman o 2009 Frank van Diggelen All rights reserved. Printed and bound in the United States of America. No part of this book may be reproduced or utilized in any form or by any means, elec- tronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher all terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Artech House cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark 10987654321 Contents Foreword Preface Acknowledgments CHAPTER T Introduction 1.1 A-GPS Overview 1.2 Book structure 1.3 Civilian Signals 1.4 Theoretical and Practical Approach 1.5 Terminology: A-GPS, A-GNSS 1.6 For Whom Is This book intended? 1.7 What's New? 13455667 References CHAPTER 2 Standard gps review 2.1 Overview: How GPS Was Designed to Work 2.1.1 Chapter outline 10 2.2 GPS Signal Power 2, 3 Satellite Orbits 12 2.4 Satellite clocks 2.5 Ephemeris 22 2.6 GPS Signals 23 2.7 Basic gps receiver functions 26 2.7.1 Mixers 27 References 29 CHAPTER Assistance, the a in A-GPS 31 3. 1 Acquisition and Assistance overview 3.1.1 Introduction to Frequency/ Code-Delay Search Space 31 3.1.2 Quantitative Overview 31 3.1.3 Cold. Warm and Hot starts 33 3.1.4 Assistance 34 3.1.5 Chapter Outline 35 3.2 Frequency and Code-Delay Search Space 35 3.2.1 Satellite motion 36 Contents 3.2.2 Receiver motion 37 3.2. 3 Receiver Oscillator Offset 37 3.2.4 Code-Delay 38 3.3 Frequency/ Code-Delay Search with Standard GPS 38 3.3.1 Hardware and Software Receivers, Sequential and parallel Searches 38 3.3.2 Frequency Bin Spacing 39 3.3.3 Typical Acquisition Scheme, Autonomous Cold Start 39 3.3.4 Typical Acquisition Scheme, Warm Start 42 3.3.5 Typical Acquisition Scheme, Hot Start 42 3.4 Tracking, Reacquisition, and assistance 42 3.4.1 The Acquisition Conundrum and Fundamental Idea of A-GPs 43 3.5 MS-Assisted and Ms-Based GPS 43 3.6 A-GPS Frequency Assistance 44 3.6.1 MS-Based Frequency assistance 44 3.6.2 MS-Assisted Frequency Assistance 45 3.6.3 Assistance Frequency Error Analysis: Time 45 3.6.4 Assistance-Frequency Error Analysis: Reference Frequency and speed 46 3.6.5 Assistance Frequency error Analysis: Position 47 3.6.6 Assistance Frequency Error Analysis: Almanac or Ephemeris 49 3.7 A-GPS Time Assistance for Code delay 49 3.7.1 MS-Based fine-Time assistance 50 3.7.2 MS-Assisted Fine-Time assistance 3.7.3 Code-Delay assistance Error Analysis: Fine-Time 3.7.4 Code- Delay Assistance Error Analysis: Position 3.7.5 Code-Delay Assistance Error Analysis: Almanac or Ephemeris 54 3. 8 Typical Acquisition Scheme, Assisted Cold Start 3.8.1 Coarse-Time, Frequency Search 3.8.2 Fine-Time, Code-Delay Search 3.8.3 Coarse-Time, Code-Delay Search References 60 CHAPTER 4 Coarse-Time Navigation Instant GPS 4.1 Overvie 61 4.1.1 Precise and Coarse Time in Navigation 61 4.1.2 Chapter outline 63 4.2 Navigation, Algebraic Description 64 4.2.1 Terminology and the observation Matrix H 67 4.3 Navigation Equations with Coarse Time 4.3. 1 Other Approaches to Coarse Time 71 4.4 Millisecond Integers and Common bias 4.4.1 Examples of the Effect of Common Bias 73 4.4.2 Solving for Millisecond Integer Ambiguity 81 4.5 Further Navigation Details 97 4.5.1 Common Bias. Not Clock bias Contents 4.5.2 Satellite Clock error 97 4.5.3 Coordinate Systems 98 4.5.4 Pseudomeasurements 99 4.5.5 Practical Considerations 100 References 101 CHAPTER 5 Coarse-Time Dilution of Precision 103 5.1 Overview--Horizontal Dilution of Precision, Accuracy, and 3GPP Standards 103 5.1.1 HDOP and Accuracy 103 5.1.2 3 GPP Standards and Real World examples 105 5.1.3 Chapter Outline 105 5.2 Extra-State Theorem 105 5.2.1 Special Case of GDOP 106 5. 2.2 Positive definite and Semidefinite Matrices 107 5.2. 3 General Case for Any DOp 108 5.2.4 equivalence 109 5.2.5 Upper bound 114 5.2.6 Consequences for 2D Navigation 115 5.3 Coarse-Time HDOP Examples 115 5.3.1 3GPP Standardized scenarios 115 5.3.2 GPS Constellation (30 Satellites 123 5.3.3 GNSS Constellation(60 Satellites) 125 References 126 CHAPTER 6 High sensitivity: Indoor GPS 127 6.1 Overview 127 6.1.1 Chapter Outline 131 6.2 Standard GPS Receiver Architecture 132 6.3 Front-End Analysis 133 6.3.1 Front-End Worksheet 136 6.3.2 Front-End Noise Figure 137 6.3.3 dBm and dB-Hz 137 6.3.4 Sky Noise and Simulator noise 139 6.4 Correlation and Coherent Integration 140 6.4.1 Correlation and Ideal coherent Integration 140 6.4.2 Implementation Losses 144 6.4.3 SNR Worksheet 158 6.5 High-Sensitivity Receiver Architecture 160 6.5.1 Counting Correlators 161 6.5.2 Correlator Size Versus Integration Time 162 6.6 Longer Coherent Integration Times 163 6.6.1 Data Bit Transitions and Data Wipe-Off 164 6.6.2 Data Bit Alignment 164 Contents 6.6.3 Maximum Frequency Error Versus Coherent-Integration Time 167 6.6.4 Maximum Velocity Versus Coherent-Integration Time 168 6.7 I, Q Squaring and Noncoherent Integration 171 6.7.1 I, Q Channels 171 6.7.2 RSS and Squaring Loss 172 6.7.3 Deriving the Squaring Loss Analytically 175 6.7.4 Evaluating the Squaring loss experimentally 180 6.7.5 Noncoherent Integration 184 6.8 High-SenSitivity SNR Worksheet 186 6.8.1 Coarse-Time Acquisition 186 6.8.2 Coherent Interval and Frequency bins 187 6.8.3 Fine-Time Acquisition and Tracking 191 6.8.4 Detection Thresholds. Pfa and PD 193 6.8.5 Achievable Sensitivity plots 201 6.8.6 Sensitivity Versus Correlator Size 206 6. 9 Other Sensitivity Considerations 208 6.9. 1 Hardware and Software Approaches 208 6.9.2 Technology Evolution 211 6.9.3 Signal Strengths in Practice and Attenuation Through Different materials 215 6.9.4 Multipath and Pure reflections 217 6.9.5 Crosscorrelation 219 6.9.6 Testing the snr Worksheet with Real signals 219 6.10 High Sensitivity Summary 221 References 221 CHAPTER 7 Generating Assistance data 225 7.1 Overview 225 7.1.1 Chapter Outline 227 7.2 Reference Stations 228 7. 3 Worldwide reference Network 229 7.3.1 Public Reference Networks 229 7.3.2 Proprietary Commercial Reference Networks 230 7.3.3 Benefits of a Worldwide reference Network 233 7.4 Initial position in assistance data 236 7.5 Handset-Generated Peer-to-Peer Assistance 237 7.5.1 Time Synchronization 237 7. 5.2 Orbit data 237 References 238 ChAPTER 8 Ephemeris Extension, Long-Term Orbits 239 8.1 Overview assistance When there is no assistance 239 8.1. 1 Chapter Outline 242 Contents 8.2 Generating Ephemeris Extensions 243 8.2.1 Using a Worldwide reference Network--One Week of Orbits 244 8.2.2 Using a Worldwide reference Network and ephemeris Decoded at a mobile device -One month of orbits 249 8.2.3 Using only ephemeris decoded at a Mobile device-Dail Repeat of orbits 250 8.2.4 Comparing Accuracy Metrics 252 8.2.5 Ephemeris Extension Accuracy Summar 254 8.2.6 Accuracy of First Fixes with Ephemeris Extensions 256 8.3 Enhanced Autonomous Using Ephemeris Extensions in Place of full a-gps assistance 256 8.3. 1 Computing Position from Doppler Measurements 258 8.3.2 Computing Position from a Mix of doppler and full Pseudorange measurements 268 8.4 Integrity Monitoring-Dealing with Changes in Orbits and Clocks 269 8.4.1 NANUS 270 8.4.2 Monitoring Broadcast Ephemeris 270 8.4.3 Receiver Autonomous Integrity Monitoring--Integrity Monitoring in the mobile device 271 References 271 CHAPTER R9 Industry Standards and Government Mandates 275 9.1 Overview 275 9. 1.1 Positioning Methods, Method Types, and Location requests 275 9.1.2 Industry Standards organization 278 9.1.3 Performance Standards 280 9.1.4 De Facto Standards: ME-PE MEIF 280 9.1.5 Chapter Outline 281 9.2 3GPP Location Standard 281 9.2.1 GSM-RRLP Protocol Specification 281 9.2.2 UMTS-RRC Protocol Specification 282 9.2.3 Other Relevant 3GPP Standards 282 9.33GPP2 283 9.4 OMA-SUPL 283 9.5 Minimum Operational Performance for A-GPS Handsets 284 9.5.13GPP 284 9.5.23GPP2 286 9.6 Measurement Engine-Position Engine (ME-Pe 288 9.6.1 Background: Assistance Data Brings Complexity 288 9.6.2 ME-PE Architecture 288 9.6. 3 Nokia ME Interface(MEIF 290 9.6.4 Implementation of MEIF 291 9.7 Government Mandates 291 9.7.1 E911-United State 291 9.7.2 E112--Europe 293