Position, Navigation and TimingAdvisory Board:

Strategic Engagement & Communication

March 27-28, 2008

SE&C - UpdateIntro

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

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’”

Recommendations (1)

Situational awarenessGPS as global critical infrastructure requires a means to

measure, detect, and geolocate interferenceReview National PNT Plan for Interference Detection and Mitigation, and Implementation PlanExplore 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(?)

Recommendations (2)

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 forClimate change, natural hazards, sea level rise, ice, earthquakes, volcanoes, tsunamis, weather, space weather, gravity fieldGroup on Earth Observation / System of Systems: GEO/GEOSSEngagement 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

Recommendations (3)

Report on Situational awarenessContribute to transition reportOther to be developed

Monitoring, ITRF, & Timing - GGTO, …

Next meeting:US Dept of AgricultureGPS as a key tool for understanding climate changeOptions for independent monitoringGalileo expert briefing

Plans

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 madeFirst meeting April 7, 2008

GPS Policy Affects Civil Use - 1980

Why Monitor?Monitoring allows 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.

DefinitionsMonitor: 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 applicationSystem 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

We Trust ‘Our’ SourcesNational 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?