Global Navigation
Satellite Systems
Report of a Joint Workshop of the National Academy of Engineering
and the Chinese Academy of Engineering
Edited by Lance A. Davis, Per K. Enge, and Grace X. Gao
NATIONAL ACADEMY OF ENGINEERING
OF THE NATIONAL ACADEMIES
THE NATIONAL ACADEMIES PRESS
Washington, D.C.
www.nap.edu
THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001
NOTICE: This publication has been reviewed according to procedures approved by the National Academy of Engineering report review process. Publication of signed work signifies that it is judged a competent and useful contribution worthy of public consideration, but it does not imply endorsement of conclusions or recommendations by the National Academy of Engineering. The interpretations and conclusions in such publications are those of the authors and do not purport to present the views of the council, officers, or staff of the National Academy of Engineering.
This project was supported by funding from the National Academies and the National Academy of Engineering Fund. Any opinions, finding, or conclusions expressed in this publication are those of the workshop participants.
International Standard Book Number 13: 978-0-309-22275-4
International Standard Book Number 10: 0-309-22275-3
Copies of this report are available from the National Academies Press, 500 Fifth Street, NW, Keck 360, Washington, DC 20001; (888) 624-8373 or (202) 334-3313; www.nap.edu.
For more information about the National Academy of Engineering, visit the NAE home page at www.nae.edu.
Copyright 2012 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
THE NATIONAL ACADEMIES
Advisers to the Notion on Science, Engineering, and Medicine
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council.
This page intentionally left blank.
WORKSHOP STEERING COMMITTEE
BRADFORD W. PARKINSON, Edward C. Wells Professor of Aeronautics and Astronautics Emeritus, Stanford University
PER K. ENGE, Professor, Department of Aeronautics and Astronautics, Stanford University
LIU JINGNAN, Member, Chinese Academy of Engineering
Staff
LANCE A. DAVIS, Executive Officer, National Academy of Engineering
GRACE X. GAO, Rapporteur and Engineering Research Associate, Global Positioning System Laboratory, Stanford University
PENELOPE GIBBS, Senior Program Associate, NAE Program Office
PROCTOR P. REID, Director, NAE Program Office
U.S. DELEGATION
National Academy of Engineering
CHARLES M. VEST, President, National Academy of Engineering
LANCE A. DAVIS, Executive Officer, National Academy of Engineering
PER K. ENGE, Professor, Department of Aeronautics and Astronautics, Stanford University
BRADFORD W. PARKINSON, Edward C. Wells Professor of Aeronautics and Astronautics Emeritus, Stanford University
PROCTOR P. REID, Director, Program Office, National Academy of Engineering
CHARLES R. TRIMBLE, Chairman, U.S. Global Positioning System Industry Council
GPS Systems and Application Experts
PENINA AXELRAD, Professor, Department of Aerospace Engineering Sciences, Colorado Center for Astrodynamics Research, University of Colorado, Boulder
GRACE GAO, Engineering Research Associate, Global Positioning System Laboratory, Stanford University
RITA LOLLOCK, General Manager, Navigation Division, The Aerospace Corporation
MICHAEL O’CONNOR, Consultant and Principal, O’C and Associates
THOMAS D. POWELL, Systems Director, Navigation Division, The Aerospace Corporation
STUART RILEY, Manager, Signal Processing and Electronic Hardware Group, Engineering and Construction Division, Trimble Navigation
A.J. VAN DIERENDONCK, GNSS Consultant, AJ Systems
TODD WALTER, Senior Research Engineer, Department of Aeronautics and Astronautics, Stanford University
U.S. Government
LEO ELDREDGE, Manager, GNSS Group, Air Traffic Organization, Federal Aviation Administration
DAVID A. TURNER, Deputy Director, Space and Advanced Technology, U.S. Department of State
CHINESE DELEGATION
Chinese Academy of Engineering
ZHOU JI, President
BAI YULIANG, Secretary General
LIU JINGNAN, CAE member
SHEN RONGJUN, CAE member
WANG LIHENG, CAE member
Department of International Cooperation of CAE
XU JIN, Deputy Director-General
ZHENG XIAOGUANG, Assistant Director-General
WANG XIAOWEN, Deputy Director
YUAN MIN, Program Officer
Chinese Academy of Sciences
SUN JIADONG, CAS Member
YANG YUANXI, CAS Member
Research Institutes
CHEN JINGPING, Senior Engineer, Beijing Global Information Center of Application and Exploitation
DING QUN, Researcher, Xi’an Research Institute of Navigation
DING XIANCHENG, Researcher, China Electronics Technology Group Corporation
DU XIAODONG, Researcher, Beijing Research Institute of Telemetry
LI ZUHONG, Researcher, China Academy of Space Technology
LU XIAOCHUN, Researcher, National Time Service Center, Chinese Academy of Sciences
TAN SHUSEN, Researcher, Beijing Global Information Center of Application and Exploitation
WANG LI, Researcher, China Aerospace Science and Technology Consultant Corporation
WU HAITAO, Researcher, Satellite Navigation Headquarters, Chinese Academy of Sciences
Corporation
HAN SHAOWEI, Researcher, Unicore Communications Inc.
Chinese Government
CAI LANBO, Vice Director, China Satellite Navigation Office
GUO SHUREN, Researcher, China Satellite Navigation Office
LU JUN, Senior Engineer, China Satellite Navigation Office
RAN CHENGQI, Director, China Satellite Navigation Office
YANG CHANGFENG, Deputy Chief Designer of Beidou Navigation Satellite System
YANG JUN, Vice Director, China Satellite Navigation Office
Industry Administrative Departments
BAI SHULIN, Deputy Director, Joint Center of GNSS, Ministry of Education, China, and Deputy Director, Advanced Technology Institute, Peking University
LU XIAOPING, Inspector, Civil Aviation Administration of China
Preface
The Global Positioning System (GPS) has revolutionized the measurement of position, velocity, and time. It has rapidly evolved into a worldwide utility with more than a billion receiver sets currently in use. Applications include emergency services, aircraft landing, farm tractor auto steering, and measurements of Earth tectonic motion, with new applications appearing every year. There are enormous benefits to humanity: improved safety of life, increased productivity, and wide-spread convenience. Recognizing this utility, Russia is rejuvenating its satellite navigation system, GLONASS. Other nations are now deploying new Global Navigation Satellite Systems (GNSSs) of their own: the European Galileo system and the Chinese System called Compass or BeiDou. Regional satellite systems are also being deployed: Japan’s Quasi-Zenith Satellite System (QZSS) and the Indian Regional Navigation Satellite System (IRNSS). All of humanity will benefit if these systems can operate as one super system, with users able to navigate using any four satellites.
The GPS constellation may decline in size over the next five years (from the current 31 satellites). This will reduce signal availability for those GPS-only users whose views of the sky are restricted by mountains, canopy, and/or city buildings. An expanded constellation of satellites providing more signals would significantly improve system access and reliability for these sky-impaired users. Moreover, a frequency diversity of signals provided by an expanded constellation would help mitigate inadvertent radio frequency interference with the weak GPS signal.
The deployment of the new and modernized satellite systems has the potential to greatly reduce signal outages—but only if their system and signal specifications are well understood, interoperable, and officially supported so that receivers can
be manufactured and their integrity assessed. The Russians and Europeans have provided significant information to the United States with respect to their signal and systems details. At the time of the workshop, held on May 24 and 25, 2011, in Shanghai, China, the Chinese authorities had not released an official description of its civil signals, and many of the U.S. delegates expressed a wish for this critical information. As the report was going to press, China released this crucial document in December 2011, seven months after the workshop described herein occurred.
Our bilateral workshop’s goal was to promote technical and policy-related cooperation between the United States and China regarding their respective navigation satellite systems—the U.S. Global Positioning System and the Chinese Compass system—to the benefit of China, the United States, and GNSS users worldwide. The workshop sought to encourage greater transparency regarding the technical and operational details that would allow the two countries to exchange system- and signal-level specifications. The recent exchange of data will improve the accuracy and availability of real-time position, navigation, and time data for all users worldwide. This exchange will foster the interchangeability of satellite signals, which will greatly decrease outages, particularly for sky-impaired users.
The workshop organizers would like to thank the National Academy of Engineering and the Chinese Academy of Engineering for their support of this workshop. We would also like to thank all the workshop participants for their thoughtful presentations and discussion.
Bradford W. Parkinson Per K. Enge Liu Jingnan
Acknowledgments
This summary has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Academies. The purpose of the independent review is to provide candid and critical comments to assist the NAE in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Charles Trimble, GPS Industry Council
Charles Elachi, Jet Propulsion Laboratory
Thomas Herring, Massachusetts Institute of Technology
Anthony Russo, National Coordination Office for Space-Based Positioning, Navigation and Timing
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the views expressed in the report, nor did they see the final draft of the report before its release. The review of this report was overseen by Julia M. Phillips, Sandia National Laboratories. Appointed by NAE, she was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authors and NAE.
This page intentionally left blank.
Contents
As Reported by Grace Xingxin Gao
(In the order of the workshop. Representing the views of the authors as presented by the speaker noted on the agenda, Appendix A.)
Development of the BeiDou Navigation Satellite System
U.S. GPS Policy, Programs and International Cooperation Activities
The Interchangeability Problem: Signals, Coordinate Frames, and Time
Rita M. Lollock, Thomas D. Powell, and Thomas A. Stansell
COMPASS/BeiDou Coordinate and Time Reference Systems
Yang Yuanxi, Tang Jing, and Han Chunhao
A Global Safety of Life Service from Multiple GNSS Constellations
Monitoring and Assessment of GNSS Open Services
Jiao Wenhai, Ding Qun, Li Jian-wen, Lu Xiaochun, and Feng Laiping
Alternative Position, Navigation, and Timing: The Need for Robust Radionavigation
Mitchell J. Narins, Leo V. Eldredge, Per Enge, Sherman C. Lo, Michael J. Harrison, and Randy Kenagy
Analysis of the GNSS Augmentation Technology Architecture
Impact of Intentional, Low Power, In-Band, Personal Privacy Devices (PPDs) on Aviation
GNSS Open Signals Interference Issues and Countermeasures
Du Xiaodong, Wang Feixue, and Nie Junwei
Present and Future Applications of COMPASS Navigation Satellite System
Application of GNSS to Environmental Studies
Recent Progress on GNSS Seismology
Liu Jingnan, Fang Rongxin, and Shi Chuang
Precision Agriculture: Opportunities and Challenges
This page intentionally left blank.
