SE&C - Update

1. Position, Navigation and TimingAdvisory Board:Strategic Engagement & CommunicationMarch 27-28, 2008

2. SE&C - Update • Intro • PNT Hill Day - March 14 • ICG involvement • Asia Pacific Economic Cooperation - GNSS Implementation Team, Meeting • May 26-30 Bangkok - outreach/engagement opportunity • Situational awareness - approach • Panel recommendations & plans • Varia

3. Recommendations (1) • 30+ satellite constellation critical for ALL user applications • Assured availability, accuracy, integrity • Explore constellation orbit design wrt GLONASS/Galileo and Beutler/Flohrer analysis - see Beutler presentation • Performance, inter-system biases and ‘interchangeability’ issues… 6 or more sats visible for assured performance • US security (domestic, ecomomic, int’l US interests) disaster response in urban areas, operations in mountainous terrain, face same issues of signal availability • Satellite laser-ranging retro-reflectors should be placed on GPS satellites as soon as possible • “Independent accuracy checks are mandatory, not a luxury’”

4. Recommendations (2) • Situational awareness GPS as global critical infrastructure requires a means to measure, detect, and geolocate interference • Review National PNT Plan for Interference Detection and Mitigation, and Implementation Plan • Explore demonstration of IDM instruments, sub-group to be led by Terry McGurn • Confirmation of policy ‘openly available, no user fees’ • Emphasize importance in implementation & in practice of common reference frame and timing • ITRF & GGTO(?)

5. Recommendations (3) • Ensure adequate funding for space and ground infrastructure, critical • Global geodetic infrastructure and assured, stable resources for all agencies involved; leadership model of support for int’l investments • Underscore importance of GPS for • Climate change, natural hazards, sea level rise, ice, earthquakes, volcanoes, tsunamis, weather, space weather, gravity field • Group on Earth Observation / System of Systems: GEO/GEOSS • Engagement in Africa - AFREF, training and coordination meetings • Support needed in developing countries to bridge digital divide • US-China Workshop May, Boulder - Earthquake Research • GPS key component

6. Plans • Report on Situational awareness • Contribute to transition report • Other to be developed • Monitoring, ITRF, & Timing - GGTO, … • Next meeting: • US Dept of Agriculture • GPS as a key tool for understanding climate change • Options for independent monitoring • Galileo expert briefing

7. National Research Council's Committee: National Requirements for Precision Geodetic Infrastructure • Statement of task:Improvements in positioning, navigation, and timing have always driven exploration and understanding of our world. Recognizing the national importance of maintaining and improving the global, high precision geodetic infrastructure that is fundamental to scientific discovery and leadership, and their applications to societal well-being and a vast array of commercial activity, an NRC committee will: • Describe and assess the range of benefits to the nation that are dependent on high precision geodetic networks; • Review high priority scientific objectives that are dependent on geodetic networks; • Describe the infrastructure requirements for achieving these objectives and benefits; • Assess the opportunities for technological innovation that will arise from renewed investment in geodetic infrastructure; • Recommend a national plan for the implementation of a precision geodetic infrastructure. No budgetary recommendations will be made First meeting April 7, 2008

9. GPS Policy Affects Civil Use - 1980

10. Why Monitor? • Monitoringallows characterization of a systems processes, determines any inherent variability, determines whether or not the system is in control, and ultimately helps to optimize performance and control. • Monitor and control permit system assessment, management, failover mode decisions, and quality assurance of the system or its output. • Monitoring is based on requirements and/or performance specifications.

11. Monitor: to watch, observe, or check closely or continuously, to keep track of systematically with a view to collecting information Accuracy: nearness to truth, how close a measurement is to the real value. Correctness of information can be measured in the form of a quantitative value given for a parameter Precision: the ability of a measurement to be consistently reproduced, the quality of being reproducible in amount or performance. Consistency: a first measure of quality and integrity. Integrity: the quality relating to trust which can be placed in the correctness of the information supplied by the total system; assurance of availability, quality and reliability. Integrity risk: probability of an undetected failure a specified system accuracy. Integrity includes the ability of a system to provide timely warnings to the user when the system should not be used for the intended operation or application System monitoring: describe system performance with respect to specifications; normally a part of the system. Performance assessment: characterize system in terms of a relevant metric; performance characterization independent of the system, external Definitions

12. We Trust ‘Our’ Sources • National Weather Service (NWS) has a component called the NWS Cooperative Program • Willingness to use a variety of data sources • Probably weight their own station data highest when it comes (eg.) declaring a tornado warning • Train ordinary people to describe and report weather conditions • Information feeds back into their system as an enhancement, augmentation, and finer sampling • Lessons learned for GPS? Great opportunity for leveraging low investment - coordination required Neighborhood watch for GPS/GNSS?