GLOBAL POSITIONING SYSTEM

1. GLOBAL POSITIONING SYSTEM Space Enterprise Council Capitol Hill Day 14 March 2008 Major Charlie Daniels, U.S. Air Force National Coordination Office

2. What You Know… • Like the Internet, GPS is a critical component of the global information infrastructure • Scalable applications enabling broad new capabilities • Facilitating innovations in efficiency, safety, environmental, public security and science • Over the past decade, GPS has grown into a global utility providing space-based positioning, navigation and timing (PNT) • Consistent, predictable, dependable performance • Augmentations improve performance

3. Briefing Overview • GPS System • GPS Applications • GPS Modernization

4. GPS Introduction • Owned and operated by the U.S. Government • Paid for by U.S. taxpayers • Managed at a national level as multi-use asset • Acquired and operated by the U.S. Air Force on behalf of the U.S. Government per Title 10, Section 2281. • GPS service is a one-way broadcast, like FM radio • Unlimited number of users • Access to civilian GPS signals is free of direct user fees • Public domain documentation • Available on an equal basis to users and industry • Anyone in the world can develop GPS user equipment

5. Master Control Station (MCS) Advanced Ground Antenna Ground Antenna (GA) Monitor Station (MS) National Geospatial-Intelligence Agency (NGA) Tracking Station Alternate Master Control Station (AMCS) FAIRBANKS ENGLAND COLORADO SPRINGS SOUTH KOREA USNO WASH D.C. VANDENBERG, AFB CAPE CANAVERAL BAHRAIN Master Control Station HAWAII KWAJALEIN ASCENSION ECUADOR DIEGO GARCIA TAHITI SOUTH AFRICA ARGENTINA NEW ZEALAND GPS Segments Space Segment Satellite Constellation User Segment Ground Antennas AFSCN MonitorStations Master Control Station Control Segment

6. GPS Ground Control Segment • Navigation message generation • Satellite position data • Monitor L-Band signals • Adjust GPS signal as needed • Command & Control satellites • Perform maneuvers • Monitor satellite health The control segment keeps the GPS constellation operating and performing within specification

7. GPS User Segment • Unlimited • Broadcast system • More users can join system • U.S. & International • Multi purpose • Civil • Military • Commercial 18

8. GPS Space Segment • 14 Block IIA satellites • 12 Block IIR satellites • 5 Block IIR-M satellites • Transmitting new second civil signal (L2C) • Transmitting new military signal (M code) • Next launch: March 15, 2008 31 GPS SatellitesSet Healthy (as of 10 Mar 08) (Baseline Constellation: 24) 30 Years of Success First Operational Launch 22 Feb 1978

9. Performance Standard Decreasing range error Year Continuous Performance Improvement Accuracy • Global GPS civil service performance commitment • continuously met since 1993

10. GPS Constellation StatusSatellite Age as of March 2008 16 14 12 10 Years 8 6 BLOCK IIA BLOCK IIR BLOCK IIR-M 4 2 Satellite 23 24 25 26 27 53 52 58 57 55 39 35 34 36 33 40 30 38 43 46 37 61 32 47 59 60 51 44 41 54 56 45

11. GPS Applications • Civil/Commercial briefed earlier • Military Applications • Force location • Navigation • Force employment • Weapon guidance • All weather ops • Satellite positioning • Comm network timing 18

12. GPS – Force Multiplier • WWII Schweinfurt-Regensburg Raids: • Dropped 24 million pounds of bombs to strike 5 ball bearing plants • 376 B-17s = 5 Targets Hit

13. All Segment – GPS Modernization Satellites • Modernized (Block IIR-M) • 2nd civil signal (L2C) • M-Code signals GPS III (Block III) • Increased accuracy • Increased signal strength • Signal integrity • Search and Rescue • Common Galileosignal (L1C) • Modernized (Block IIF) • 3rd civil signal (L5) • Legacy (Block IIA/IIR) • Basic GPS • C/A civil signal (L1C/A) • Std Pos. Service • Precise Pos. Service • L1 & L2 P(Y) nav Control Systems OCX (Modernized) • New Architecture • L1C, L2C, L5, M-Code • Flex Power Legacy • TT&C • L1 & L2 monitoring Upgraded (AEP) • IIR-M IIF TT&C • WAGE, AII, LADO • New MCS/AMCS User Equipment Upgrading • Military User Equipment

14. Modernized GPS – New Signals • Second civil signal (“L2C”) • Designed to meet commercial needs • Higher accuracy through ionospheric correction • Began with GPS Block IIR-M in Sep 2005; 24 satellites: ~2014 • Third civil signal (“L5”) • Designed to meet demanding requirements for transportation safety (safety-of-life) • Begins with GPS Block IIF • First launch: ~2008 (GPS IIR-M Demo); ~2009 (GPS IIF); 24 satellites: ~2016 • Fourth civil signal (“L1C”) • Designed with international partners to enable GNSS interoperability • Begins with GPS Block III; First launch: ~2014; 24 satellites: ~2021

15. Benefits of GPS Modernization • System-wide improvements in accuracy, availability, integrity, and reliability to: • Meet increasing civil, commercial and military demands • Remain the pre-eminent space-based military PNT system • Higher standalone accuracy • More robust against interference • Provides separate more secure Military signal • Capability for second (L2C) and third (L5) civil signals • Delivers L1C for interoperability with other GNSS • Improved indoor, mobile, and urban use

16. Summary • GPS System • 3 Segments; Ground Control, Space and User • Sustaining aging constellation while providing best accuracy • GPS Applications • Unlimited civil/commercial global user capacity • Military users • GPS Modernization • Key to meeting emerging civil/commercial demands • Key to remaining the preeminent military space-based PNT service GPS – The World’s Gold Standard in Space-Based PNT Services

17. Contact Info Major Charles Daniels, U.S. Air Force National Coordination Office for Space-Based PNT 1401 Constitution Ave, NW, Room 6822 Washington, DC 20230 Tele: 202-482-6726 Email: charles.daniels@pnt.gov Web sites: http://pnt.gov http://gps.gov