1. Updated November 2009 Global Positioning System

2. What is GPS? A worldwide radio wave-navigation system formed from a constellation of 24 satellites and their ground stations GPS uses these “man-made stars” as reference points to calculate positions accurate to a matter of meters A worldwide radio wave-navigation system formed from a constellation of 24 satellites and their ground stations GPS uses these “man-made stars” as reference points to calculate positions accurate to a matter of meters

3. GPS Constellation

4. Who Developed GPS? U.S. Department of Defense spent $12 billion to create a super precise form of worldwide positioning In the late days of the arms race, the U.S. military needed to be able to take out Russia’s missile system That ability profoundly affected the balance of power U.S. Department of Defense spent $12 billion to create a super precise form of worldwide positioning In the late days of the arms race, the U.S. military needed to be able to take out Russia’s missile system That ability profoundly affected the balance of power

5. Pre – GPS Sputnik launched in 1957 by Russia Scientists at MIT learned they could track Sputnik’s orbit by listening to changes in its radio frequency as it came nearer or moved further away First step in recognizing a location on earth could be determined using radio signals from the satellite Sputnik launched in 1957 by Russia Scientists at MIT learned they could track Sputnik’s orbit by listening to changes in its radio frequency as it came nearer or moved further away First step in recognizing a location on earth could be determined using radio signals from the satellite

6. United State’s GPS NAVSTAR – the official name of the U.S. Global Positioning System First deployed satellites in the 1970s The satellite completing NAVSTAR was deployed in the 1990s NAVSTAR – the official name of the U.S. Global Positioning System First deployed satellites in the 1970s The satellite completing NAVSTAR was deployed in the 1990s

7. NAVSTAR Satellite

8. Land vs. Sea Russia’s nuclear system was on land U.S. nuclear arsenal was largely at sea on submarines For precise targeting, a system must have accurate launching coordinates as well as precise target coordinates A submarine must surface and accurately fix its exact position quickly using GPS Russia’s nuclear system was on land U.S. nuclear arsenal was largely at sea on submarines For precise targeting, a system must have accurate launching coordinates as well as precise target coordinates A submarine must surface and accurately fix its exact position quickly using GPS

9. GPS Signals Originally for military purposes The U.S. government/military could “fuzz” the signals which weakened the signal making it less accurate Could also completely disable the signals to the public (& other countries!) through encryption Originally for military purposes The U.S. government/military could “fuzz” the signals which weakened the signal making it less accurate Could also completely disable the signals to the public (& other countries!) through encryption

10. Ground Control Segments Also known as Control Segments Check both the operational health and exact position of satellite in space Transmit corrections Five Ground Control Segments: Hawaii, Ascension Island, Diego Garcia, Kwajalein, and Colorado Springs Also known as Control Segments Check both the operational health and exact position of satellite in space Transmit corrections Five Ground Control Segments: Hawaii, Ascension Island, Diego Garcia, Kwajalein, and Colorado Springs

11. Land Control Segments

12. How Does GPS Work Satellites broadcast radio signals to Earth with information about their location and the exact time the signal was transmitted (each satellite carries an atomic clock).

13. How it Works, continued By calculating the difference between radio signals received from four or more satellites(originally used 3 for triangulation), GPS receivers on the ground can determine their own location (latitude/longitude), and elevation with great accuracy.

14. Civilian Demand Civilian demand for GPS products surged in 2000 when military stopped “fuzzing” signals Overnight, navigation devices became 10 times more accurate Civilian demand for GPS products surged in 2000 when military stopped “fuzzing” signals Overnight, navigation devices became 10 times more accurate

15. Civilian Uses Fishing to freight to fleet tracking Navigation (cars, train, boats, planes) ONSTAR, emergency vehicles In phones, wristwatches & dog collars Geocaching – 800,000 active "caches” Construction, moviemaking, farming equipment Fishing to freight to fleet tracking Navigation (cars, train, boats, planes) ONSTAR, emergency vehicles In phones, wristwatches & dog collars Geocaching – 800,000 active "caches” Construction, moviemaking, farming equipment

16. Scientific Use Meteorologists gauge wind speed and other variables Zoologists track endangered species Geologists study earthquakes Technicians synchronize computer networks for power grids to financial networks Meteorologists gauge wind speed and other variables Zoologists track endangered species Geologists study earthquakes Technicians synchronize computer networks for power grids to financial networks

17. Effects on Economy GPS receivers have been miniaturized to just a few integrated circuits, thus cheaper Worldwide GPS market will total $75 billion by 2013 100,000 jobs GPS receivers have been miniaturized to just a few integrated circuits, thus cheaper Worldwide GPS market will total $75 billion by 2013 100,000 jobs

18. Updating NAVSTAR Satellites are regularly replaced as they age and fail As of 2009 there are currently more than 30 in space Extras used as spares and backups Updating signals/frequencies to work with other systems Satellites are regularly replaced as they age and fail As of 2009 there are currently more than 30 in space Extras used as spares and backups Updating signals/frequencies to work with other systems

19. Russia’s GLONASS First satellite deployed in 1970s Operational in the 1990s 21 satellites originally + 2 from India Can disable use by others through encryptions All ground control segments are located within the former Soviet Union First satellite deployed in 1970s Operational in the 1990s 21 satellites originally + 2 from India Can disable use by others through encryptions All ground control segments are located within the former Soviet Union

20. Europe’s GNSS Galileo should be operational sometime between 2010-2013 Full precision for military and civilian use Will have 30 satellites Bases in Germany and Italy Galileo should be operational sometime between 2010-2013 Full precision for military and civilian use Will have 30 satellites Bases in Germany and Italy

21. Galileo goes International Created by European Union(27 members) China, Israel, Ukraine, Morocco, South Korea, Norway joined efforts with Galileo Neutral technology available to everyone Created by European Union(27 members) China, Israel, Ukraine, Morocco, South Korea, Norway joined efforts with Galileo Neutral technology available to everyone

22. Galileo’s Services Open Service – free Commercial Service – more accuracy, encrypted, available for a fee Public Regulated Service – law enforcement, military, security Safety of Life Service – safety/critical transport, air traffic control Open Service – free Commercial Service – more accuracy, encrypted, available for a fee Public Regulated Service – law enforcement, military, security Safety of Life Service – safety/critical transport, air traffic control

23. U.S. Concerns Initial frequency chosen for Galileo made it impossible to block without interfering with NAVSTAR Galileo agreed to use a different frequency allowing NAVSTAR to be jammed for national security NAVSTAR in conjunction with GALILEO is very accurate Initial frequency chosen for Galileo made it impossible to block without interfering with NAVSTAR Galileo agreed to use a different frequency allowing NAVSTAR to be jammed for national security NAVSTAR in conjunction with GALILEO is very accurate

24. Websites http://web.haystack.mit.edu/pcr/wherea mi/documents/gpstutorial.htmhttp://web.haystack.mit.edu/pcr/wherea mi/documents/gpstutorial.htm http://www.trimble.com/gps/index.html http://science.nasa.gov/Realtime/jtrack/ 3d/JTrack3D.html http://science.nasa.gov/Realtime/jtrack/ 3d/JTrack3D.html http://www.spaceandtech.com/spacedat a/constellations/glonass_consum.shtmlhttp://www.spaceandtech.com/spacedat a/constellations/glonass_consum.shtml http://web.haystack.mit.edu/pcr/wherea mi/documents/gpstutorial.htmhttp://web.haystack.mit.edu/pcr/wherea mi/documents/gpstutorial.htm http://www.trimble.com/gps/index.html http://science.nasa.gov/Realtime/jtrack/ 3d/JTrack3D.html http://science.nasa.gov/Realtime/jtrack/ 3d/JTrack3D.html http://www.spaceandtech.com/spacedat a/constellations/glonass_consum.shtmlhttp://www.spaceandtech.com/spacedat a/constellations/glonass_consum.shtml