Essentials of Positioning and Location Technology

Transcription

1 Essentials of Positioning and Location Technology Mystified by locating and positioning technologies? Need to get the best from your location system? This guide is invaluable for understanding how the positions and movements of objects can be measured and used for real-world applications. From it, you ll learn how to optimise and manage system performance by working with parameters such as velocity, orientation, time, proximity and direction, and consider not only accuracy, but also reliability, integrity, response time and uncertainty. Packed with practical examples, this concise book gives you an overview of terrestrial radiolocation techniques, including comparative system architectures and real-world performance and limitations. It describes inertial navigation principles and techniques, including low-cost MEMS sensors for consumer products, and a range of applications, such as those benefiting from hybrid positioning techniques. DAVID BARTLETT is a chartered electronics engineer and serial entrepreneur, and is currently CTO and Director of Omnisense, a Cambridge-based company, which he co-founded. He has founded or co-founded several companies, is named inventor on many patent families, and is author of a number of published articles.

2 The Cambridge Wireless Essentials Series Series Editors william webb Neul, UK sudhir dixit HP Labs, India A series of concise, practical guides for wireless industry professionals. Martin Cave, Chris Doyle and William Webb, Spectrum Management Essentials of Modern Christopher Haslett, Essentials of Radio Wave Propagation Stephen Wood and Roberto Aiello, Essentials of UWB Christopher Cox, Essentials of UMTS Steve Methley, Essentials of Wireless Mesh Networking Linda Doyle, Essentials of Cognitive Radio Nick Hunn, Essentials of Short-Range Wireless Amitava Ghosh and Rapeepat Ratasuk, Essentials of LTE and LTE-A Abhi Naha and Peter Whale, Essentials of Mobile Handset Design, Essentials of Positioning and Location Technology For further information on any of these titles, the series itself and ordering information see /wirelessessentials

3 Essentials of Positioning and Location Technology Omnisense, Cambridge

4 CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Mexico City Cambridge University Press The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York Information on this title: / Cambridge University Press 2013 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2013 Printed and bound in the United Kingdom by the MPG Books Group A catalogue record for this publication is available from the British Library Library of Congress Cataloguing in Publication data Bartlett, David, 1958 author. Essentials of positioning and location technology /, Omnisense, Cambridge. pages cm. (The Cambridge wireless essentials series) ISBN (hardback) 1. Location-based services. 2. Mobile geographic information systems. I. Title. TK B dc ISBN Hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate.

5 Contents 1 Introduction A brief historical perspective What is meant by location or positioning? Describing a position Location as a context for applications Techniques for determining the position of an object 5 2 Coordinate systems Latitude and longitude Cartesian coordinate systems Inertial coordinate frame Describing direction and orientation 26 3 Satellite positioning (GNSS) Introduction to satellite positioning Brief description of how GPS works High precision GPS systems Assisted GPS Brief descriptions of other GNSSs 54 4 Radiolocation technologies Angle of arrival Received signal strength (RSSI) to determine distance Time-of-flight range measurement Time of arrival Time difference of arrival Measuring signal arrival time Positioning using cellular mobile networks 77 v

6 vi contents 4.8 Ultrawideband (UWB) Other radiolocation systems 87 5 Inertial navigation Principle of inertial navigation Sensors used for inertial navigation Architecture of a strap-down inertial navigation system Navigation equations Brief review of the errors in the strap-down inertial system Integration with other positioning technologies Dead reckoning for vehicles Human navigation Other techniques and hybrid systems RFID and RTLS Digital compass Optical and image tracking techniques Map matching Image recognition Fingerprinting Simultaneous localisation and mapping (SLAM) Techniques and performance Understanding accuracy and precision Theoretical bounds for accuracy Techniques for assessing quality of a position fix Tracking the motion of the target When things go wrong Systems, probability and false positives Multipath Vulnerabilities and limitations of GNSS Strategies for dealing with failure 161

7 contents vii 9 Location-based services and applications Essential principles underpinning services and applications Location-based services Professional applications A brief look at the future GNSS advances Relative positioning systems Visual and optical positioning systems Privacy issues The information of positioning 191 References 193 Index 198

8 This is a comprehensive and approachable introduction to positioning systems that draws together in one book the wide variety in the subject. s no-nonsense style gives us the essence of complex and sometimes abstract ideas in an easily digestible form, backed up with plenty of references where the reader can find more information. I very much enjoyed reading the book, and think that experts and beginners alike can find here much to engage and inform. Peter Duffett-Smith, Cavendish Laboratory, University of Cambridge