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

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

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

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, GPS Satellites Set Healthy (as of 10 Mar 08) (Baseline Constellation: 24) 31 GPS Satellites Set Healthy (as of 10 Mar 08) (Baseline Constellation: 24) 30 Years of Success First Operational Launch 22 Feb Years of Success First Operational Launch 22 Feb 1978

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

Years Satellite GPS Constellation Status Satellite Age as of March BLOCK IIA BLOCK IIR BLOCK IIR-M

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

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

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 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 Tele: Web sites: