NGA s Support for Positioning and Navigation

Transcription

1 NGA s Support for Positioning and Navigation PNT Symposium 6 November 2007 Barbara Wiley NATIONAL GEOSPATIAL-INTELLIGENCE AGENCY

2 What is NGA and What Do We Do? National Geospatial-Intelligence Agency (NGA) is a National Intelligence and Combat Support Agency Mission: GEOINT Provide Timely, Relevant, and Accurate GEOINT in support of National Security Definition: The exploitation and analysis of imagery and geospatial information to describe, assess, and visually depict physical features and geographically referenced activities on the Earth. GEOINT consists of imagery, imagery intelligence, and geospatial information. Imagery Production Building Administration Building Production Facility in Country X Main Vehicle Production Post-Flood July 200x Storage Buildings Imagery Intelligence Geospatial Information 2

3 Know the Earth, Show the Way Layers in the National System of Geospatial- Intelligence (NSG) define Positioning and Navigation Maps Charts Reference Frame (WGS 84) Precise Positioning Safety of Navigation Digital Terrain Elevation Data Digital Point Positioning Database 3

4 World Geodetic System 1984 Ensure Scientific Integrity Ensure Interoperability with other global systems Prime Meridian Z 0,0,0 Reference Frame Datum Transformations Earth Gravity Models Global Vertical Datum World Magnetic Model Elevations Map/Charts X EQUATOR Y 4

5 NGA s GPS Mission 30+ years of satellite tracking Precise orbits needed to produce precise positions From the Master Positioning, Navigation and Timing Plan: NGA is responsible for: Services to support DoD navigation systems Maintenance of GPS fixed site operations Generation and distribution of GPS precise ephemerides Approved for Public Release NGA Case #

6 GPS Operations and NGA NGA GPS observations Directly improve GPS Broadcast Accuracy Directly improve GPS Integrity Monitoring NGA GPS Precise Ephemeris DoD Standard Quality control for GPS operations Earth Orientation (from USNO) Geodetic tie for GPS Earth-fixed to Inertial Frame Approved for Public Release NGA Case #

7 GPS Monitor Station Network GPS Wing designs and acquires the GPS space systems USAF operates and maintains the GPS constellation NGA provides trusted data and analysis to USAF on GPS satellites referenced to WGS 84 Approved for Public Release NGA Case #

8 NGA Precise Ephemeris for GPS is DoD Truth - Precise determination of where the satellites were - Precise GPS clock solutions - Used for precise positioning and system analysis NGA is the authoritative source for precise GPS ephemeris Approved for Public Release NGA Case #

9 Future GPS Products Estimation and Prediction of Orbits and Clocks to High Accuracy (EPOCHA) Near Real-Time, automated network distribution of orbital states to multiple customers Initially every 15 minutes Goal is every 30 seconds IOC is Summer 2009 Approved for Public Release NGA Case #

10 Inertial Navigation Systems GPS + INS + gravity = A more robust system GPS INS Gravity Data External to Weapon System 2 Navigation Solution Internal to Weapon System 1 Internal to Weapon System

11 Inertial Navigation Systems GPS + INS + gravity = A more robust system 11

12 Safety of Navigation 12

13 NATIONAL GEOSPATIAL-INTELLIGENCE AGENCY 13