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 that provide enormous benefits to humanity: improved safety of life, increased productivity, and wide-spread convenience. Global Navigation Satellite Systems summarizes the joint workshop on Global Navigation Satellite Systems held jointly by the U.S. National Academy of Engineering and the Chinese Academy of Engineering on May 24-25, 2011 at Hongqiao Guest Hotel in Shanghai, China. "We have one world, and only one set of global resources. It is important to work together on satellite navigation. Competing and cooperation is like Yin and Yang. They need to be balanced," stated Dr. Charles M. Vest, President of the National Academy of Engineering, in the workshop's opening remarks. Global Navigation Satellite Systems covers the objectives of the workshop, which explore issues of enhanced interoperability and interchangeability for all civil users aimed to consider collaborative efforts for countering the global threat of inadvertent or illegal interference to GNSS signals, promotes new applications for GNSS, emphasizing productivity, safety, and environmental protection. The workshop featured presentations chosen based on the following criteria: they must have relevant engineering/technical content or usefulness; be of mutual interest; offer the opportunity for enhancing GNSS availability, accuracy, integrity, and/or continuity; and offer the possibility of recommendations for further actions and discussions. Global Navigation Satellite Systems is an essential report for engineers, workshop attendees, policy makers, educators, and relevant government agencies. Table of ContentsFront MatterSummary of the Workshop--As Reported by Grace Xingxin GaoAddress at the Opening Ceremony of the NAE-CAE Joint Workshop onGlobal Navigation Satellite Systems (GNSS)--Zhou JiIntroductory Remarks--Charles M. VestWORKSHOP PRESENTATIONSDevelopment of the BeiDou Navigation Satellite System--Ran ChengqiU.S. GPS Policy, Programs, and International CooperationActivities--David A. TurnerResearch Report on GNSS Interoperability--Lu Xiaochun, Lu Jun, BaiYan, Han Tao, and Wang XueThe Interchangeability Problem: Signals, Coordinate Frames, andTime--Rita M. Lollock, Thomas D. Powell, and Thomas A. StansellCOMPASS/BeiDou Coordinate and Time Reference Systems--Yang Yuanxi,Tang Jing, and Han ChunhaoA Global Safety of Life Service from Multiple GNSSConstellations--Per EngeMonitoring and Assessment of GNSS Open Services--Jiao Wenhai, DingQun, Li Jian-wen, Lu Xiaochun, and Feng LaipingAlternative Position, Navigation, and Timing: The Need for RobustRadionavigation--Mitchell J. Narins, Leo V. Eldredge, Per Enge,Sherman C. Lo, Michael J. Harrison, and Randy KenagyAnalysis of the GNSS Augmentation Technology Architecture--ChenJinpingImpact of Intentional, Low Power, In-Band, Personal Privacy Devices(PPDs) on Aviation--A.J. Van DierendonckGNSS Open Signals Interference Issues and Countermeasures--DuXiaodong, Wang Feixue, and Nie JunweiPresent and Future Applications of COMPASS Navigation SatelliteSystem--Tan ShusenApplication of GNSS to Environmental Studies--Penina AxelradRecent Progress on GNSS Seismology--Liu Jingnan, Fang Rongxin, andShi ChuangPrecision Agriculture: Opportunities and Challenges--MichaelO'ConnorIntegrity Lessons from the WAAS Integrity Performance Panel--ToddWalter, Per Enge, and Bruce DeCleeneBreaking the Ice: Navigation in the Arctic--Grace Xingxin Gao,Liang Heng, Todd Walter, and Per EngeAPPENDIXESWorkshop attendees [photo]Appendix A: Workshop AgendaAppendix B: Workshop Summary RecordAppendix C: Biographical InformationAppendix D: Acronyms